MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Fly' source. Mon, 06 Feb 2012 14:26:10 +0100 http://www.medworm.com/index.php?rid=5576135&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22223092%26dopt%3DAbstract Authors: Chung YS, Kocks C Abstract Phagocytosis is an evolutionarily ancient, receptor-driven process, by which phagocytic cells recognize invading microbes and destroy them after internalization. The phagocytosis receptor Eater is expressed exclusively on Drosophila phagocytes and is required for the survival of bacterial infections. In a recent study, we explored how Eater can defend fruit flies against different kinds of bacteria. We discovered that Eater bound to certain types of bacteria directly, while for others bacterial binding was dependent on prior disruption of the bacterial envelope. Similar to phagocytes, antimicrobial peptides and lysozymes are ancient components of animal immune systems. Our results suggest that cationic antimicrobial peptides, as well as lysozymes... Fly journals http://www.medworm.com/rss/comments.php?id=5576135 Sun, 01 Jan 2012 05:00:00 +0100 5576135 http://www.medworm.com/index.php?rid=5576134&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22223093%26dopt%3DAbstract Authors: Gowaty PA Abstract Polyandry is a paradox:  why do females mate multiple times when a single ejaculate often provides enough sperm for lifetime egg production? Gowaty et al. (2010) addressed explanations for polyandry in Drosophila pseudoobscura from the perspective of hypotheses based on sex differences in costs of reproduction (CoR). Contrary to CoR, Gowaty et al. (2010) showed that (1) a single ejaculate was inadequate for lifetime egg production; (2) polyandry provided fitness benefits to females beyond provision of adequate sperm; and (3) fitness benefits of polyandry were not offset by costs.  Here, I discuss predictions of the ad hoc hypotheses of CoR and three alternative hypotheses to CoR to facilitate a discussion and further development of a strong inference a... Fly journals http://www.medworm.com/rss/comments.php?id=5576134 Sun, 01 Jan 2012 05:00:00 +0100 5576134 http://www.medworm.com/index.php?rid=5544447&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22198523%26dopt%3DAbstract Authors: Sousa-Neves R, Schinaman JM Abstract The fourth chromosome of Drosophila remains one of the most intractable regions of the fly genome to genetic analysis. The main difficulty posed to the genetic analyses of mutations on this chromosome arises from the fact that it does not undergo meiotic recombination, which makes recombination mapping impossible, and also prevents clonal analysis of mutations, a technique which relies on recombination to introduce the prerequisite recessive markers and FLP-recombinase recognition targets (FRT). Here we introduce a method that overcomes these limitations and allows for the generation of single Minute haplo-4 clones of any fourth chromosome mutant gene in tissues of developing and adult flies. PMID: 22198523 [PubMed - as supplied by ... Fly journals http://www.medworm.com/rss/comments.php?id=5544447 Wed, 28 Dec 2011 06:06:20 +0100 5544447 http://www.medworm.com/index.php?rid=5544446&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22198524%26dopt%3DAbstract Authors: Callahan BJ Abstract Central to the study of molecular evolution, and an area of long-standing debate, is the appropriate model for the fitness landscape of proteins. Much of this debate has focused on the strength and frequency of positive and purifying selection, but the form and frequency of selective correlations is also a vital element. The constituent amino acids within a protein generically interact and share selective pressures in predictable ways, which conflicts with the selective independence assumed by common caricatures of the fitness landscape. Here, I discuss a recent study by myself and coauthors that used whole-genome comparisons of orthologous molecular sequences from closely related Drosophilids to explore the form of the selective correlations and selec... Fly journals http://www.medworm.com/rss/comments.php?id=5544446 Wed, 28 Dec 2011 06:06:11 +0100 5544446 http://www.medworm.com/index.php?rid=5376483&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22041575%26dopt%3DAbstract Authors: Oxenkrug GF, Navrotskaya V, Voroboyva L, Summergrad P Abstract Upregulation of kynurenine (KYN) formation from tryptophan (TRY) was associated with aging in animal and human studies. TRY - KYN metabolism is affected by the activities of TRY 2,3-dioxygenase 2 (TDO) and ATP-binding cassette (ABC) transporter regulating TRY access to intracellular TDO. We studied the effects of TDO inhibitor, alpha-methyl tryptophan (aMT), and ABC transported inhibitor, 5-methyl tryptophan (5MT), on the life span of wild strain female Drosophila flies (Oregon-R). aMT and 5MT prolonged mean and maximum life span (by 27% and 43%, and 21% and 23%, resp.). The present results are the first observation of the extension of life span of Drosophila melanogaster by inhibitors of TRY - KYN metabolism, ... Fly journals http://www.medworm.com/rss/comments.php?id=5376483 Sat, 01 Oct 2011 04:00:00 +0100 5376483 http://www.medworm.com/index.php?rid=5376482&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22041576%26dopt%3DAbstract Authors: Marygold SJ, Walker C, Orme M, Leevers S Abstract The ebi gene of Drosophila melanogaster has been implicated in diverse signalling pathways, cellular functions and developmental processes. However, a thorough genetic analysis of this gene has been lacking and the true extent of its biological roles is unclear. Here, we characterize eleven ebi mutations and find that ebi has a novel role in promoting growth of the wing imaginal disc: viable combinations of mutant alleles give rise to adults with small wings. Wing discs with reduced EBI levels are correspondingly small and exhibit down-regulation of Notch target genes. Furthermore, we show that EBI colocalizes on polytene chromosomes with Smrter (SMR), a transcriptional corepressor, and Suppressor of Hairless (SU(H)... Fly journals http://www.medworm.com/rss/comments.php?id=5376482 Sat, 01 Oct 2011 04:00:00 +0100 5376482 http://www.medworm.com/index.php?rid=5376481&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22041577%26dopt%3DAbstract We describe an original and so far unique feeding behavior in that species. Strong black spines on the fore tarsus of both sexes are used for scratching the surface of the petals: the juice pouring out from the scratched cells is immediately ingested and this might be the only source of food. D. suma has been investigated on two kinds of flowers, Ipomoea and Crinum. In spite of the very different shape and color of these flowers, the feeding behavior of the flies is the same. Various morphological and anatomical adaptations are described, especially those related to laying a few very big eggs. The taxonomic position of D. suma has long remained and still is elusive. Further taxonomic and phylogenetic investigations would thus be needed to understand how adaptation to flower breeding has ev... Fly journals http://www.medworm.com/rss/comments.php?id=5376481 Sat, 01 Oct 2011 04:00:00 +0100 5376481 http://www.medworm.com/index.php?rid=5341433&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D22004889%26dopt%3DAbstract Authors: Kontarakis Z, Konstantinides N, Pavlopoulos A, Averof M Abstract We recently developed integrase-mediated trap conversion (iTRAC) as a means of exploiting gene traps to create new genetic tools, such as markers for imaging, drivers for gene expression and landing sites for gene and chromosome engineering. The principle of iTRAC is simple: primary gene traps are generated with transposon vectors carrying φC31 integrase docking sites, which are subsequently utilized to integrate different constructs into the selected trapped loci. Thus, iTRAC allows us to reconfigure selected traps for new purposes. Two features make iTRAC an attractive approach for Drosophila research. First, its versatility permits the exploitation of gene traps in an open-ended way, for applications that... Fly journals http://www.medworm.com/rss/comments.php?id=5341433 Sat, 01 Oct 2011 04:00:00 +0100 5341433 http://www.medworm.com/index.php?rid=5272663&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21946255%26dopt%3DAbstract Authors: Chen S, Yang H, Krisky BH, Zhang A, Long M Abstract Our recent study found that 30% of young genes were essential for viability that determines development through stages from embryo to pupae in Drosophila melanogaster, revealing rapidly evolving genetic components involved in the evolution of development. Meanwhile, many young genes did not produce complete lethal phenotype upon constitutive knockdown, suggesting that they may not be essential for viability. These genes, nevertheless, were fixed by natural selection, and might play an important functional role in their adult stage. Here we present a detailed demonstration that a newly duplicated serine-type endopeptidase gene that originated in the common ancestor in the D. melanogaster subgroup 6~11 million years ago, na... Fly journals http://www.medworm.com/rss/comments.php?id=5272663 Sat, 01 Oct 2011 04:00:00 +0100 5272663 http://www.medworm.com/index.php?rid=5225492&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21914977%26dopt%3DAbstract We describe a novel thermosensitive escape behavior in Drosophila larvae and a simple assay to accurately define the response temperature. When a larva is placed in a droplet of water that is subsequently heated, a stereotypical escape response is robustly elicited at 29°C. Larvae defective for the painless TRP receptor, or blocked in the function of class IV multi-dendritic sensory dendrites respond to this stimulus at reproducibly higher temperature (34°C). The escape response has novel behavioral components and a lower temperature threshold in comparison with the responses to touch with a hot needle. Furthermore the assay minimizes operator bias that is present in current tests of thermosensitive nociception and generates a precise determination of temperature at the point of response... Fly journals http://www.medworm.com/rss/comments.php?id=5225492 Sat, 17 Sep 2011 23:40:12 +0100 5225492 http://www.medworm.com/index.php?rid=5215442&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21897116%26dopt%3DAbstract Authors: Shieh BH Abstract Inherited retinal degeneration in Drosophila has been explored for insights into similar processes in humans. Based on the mechanisms, I divide these mutations in Drosophila into three classes. The first consists of genes that control the specialization of photoreceptor cells including the morphogenesis of visual organelles  (rhabdomeres) that house the visual signaling proteins. The second class contains genes that regulate the activity or level of the major rhodopsin, Rh1, which is the light sensor and also provides a structural role for the maintenance of rhabdomeres. Some mutations in Rh1 (NinaE) are dominant due to constitutive activity or folding defects, like autosomal dominant retinitis pigmentosa (ADRP) in humans. The third class consists of gen... Fly journals http://www.medworm.com/rss/comments.php?id=5215442 Tue, 13 Sep 2011 19:00:24 +0100 5215442 http://www.medworm.com/index.php?rid=5215441&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21904119%26dopt%3DAbstract Authors: Tsubota SI, Vogel AC, Phillips AC, Ibach SM, Weber NK, Kostrzebski MA, Spencer SA Abstract Enhancer of rudimentary, e(r), encodes a small nuclear protein, ER, that has been implicated in the regulation of pyrimidine metabolism, DNA replication, and cell proliferation.  In Drosophila melanogaster, a new recessive Notch allele, N (nd-p) , was isolated as a lethal in combination with an e(r) allele, e(r) (p2) .  Both mutants are viable as single mutants.  N (nd-p) is caused by a P-element insertion in the 5' UTR, 378-bp upstream of the start of translation.  Together the molecular and genetic data argue that N (nd-p) is a hypomorphic allele of N.  The three viable notchoid alleles, N (nd-p) , N (nd-1) , and N (nd-3) , are lethal in combination with e(r) (-) alleles.  Ou... Fly journals http://www.medworm.com/rss/comments.php?id=5215441 Tue, 13 Sep 2011 19:00:13 +0100 5215441 http://www.medworm.com/index.php?rid=5147288&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21857163%26dopt%3DAbstract Authors: Stowers RS Abstract Neural circuit mapping and manipulation are facilitated by independent control of gene expression in pre- and post-synaptic neurons. The GAL4/UAS and Q binary transcription systems have the potential to provide this capability. Of particular use in neural circuit mapping would be GAL4 and QF drivers specific for neurotransmitters and neurotransmitter receptors. Recently available Drosophila genomic BAC libraries make recombineering large genes including those specific for neurotransmitters and neurotransmitter receptors feasible. Here the functionality of cassettes that allow efficient recombineering of GAL4 and QF drivers based on kanamycin selection is demonstrated in Drosophila. The cassettes should, however, be generalizable for recombineering in ot... Fly journals http://www.medworm.com/rss/comments.php?id=5147288 Wed, 24 Aug 2011 05:24:31 +0100 5147288 http://www.medworm.com/index.php?rid=5147287&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21857164%26dopt%3DAbstract Authors: Abed M, Bitman-Lotan E, Orian A Abstract Posttranscriptional modifications of proteins by the ubiquitin and SUMO (Small Ubiquitin-related Modifier) pathways regulate the function of protein networks, enable cells to respond to signaling cues during development, and to cope with the changing environment during adult life. Both modifications can impact protein stability, localization, protein-protein interactions and/or function. While both pathways have been well studied individually, the long-speculated nature of crosstalk between SUMO and ubiquitin pathways has been molecularly enigmatic. Recent work in yeast and mammalian cells identified the connection between the two pathways in the form of a conserved family of RING finger ubiquitin ligases termed SUMO-Targeted ubiqui... Fly journals http://www.medworm.com/rss/comments.php?id=5147287 Wed, 24 Aug 2011 05:24:23 +0100 5147287 http://www.medworm.com/index.php?rid=5088385&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21785267%26dopt%3DAbstract Authors: Lattao R, Bonaccorsi S, Guan X, Wasserman SS, Gatti M We generated FM7a and CyO balancer chromosomes bearing a Tubby1 (Tb1) dominant transgene. Flies heterozygous for these FM7a and CyO derivatives exhibit a phenotype undistinguishable from that elicited by the Tb1 mutation associated with the TM6B balancer. We tested two of these Tb-bearing balancers (FM7-TbA and CyO-TbA) for more than 30 generations and found that the Tb1 transgene they carry is stable. Thus, these new Tb-tagged balancers are particularly useful for balancing lethal mutations and distinguish homozygous mutant larvae from their heterozygous siblings. PMID: 21785267 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=5088385 Wed, 03 Aug 2011 14:46:01 +0100 5088385 http://www.medworm.com/index.php?rid=5088384&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21795852%26dopt%3DAbstract Authors: Birchler JA, Xie W Mutations and most transgenes that induce ectopic cell death in Drosophila will produce an inhibitory effect on RNA interference (RNAi) in adjacent cells. When extensive cell death is sporadically induced using a heat shock promoted-head involution defective (hs-hid) transgene, molecular attributes of this inhibition can be studied. For a Green Fluorescent Protein (GFP) RNAi construct, cell death causes a greater accumulation of the mature mRNA and the double stranded RNA with an accompanying reduction in the homologous siRNAs. Endogenous transposable element expression is increased and there is an overall reduction in their corresponding siRNAs. The implications of this finding for the conduct of RNAi and potential reasons for its existence are discussed. ... Fly journals http://www.medworm.com/rss/comments.php?id=5088384 Wed, 03 Aug 2011 14:45:42 +0100 5088384 http://www.medworm.com/index.php?rid=4945789&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21654210%26dopt%3DAbstract Authors: Gettings M, Noselli S What triggers a differentiated cell to naturally change its cell fate? Cell reprogramming is a rare and intriguing phenomenon, from a developmental point of view. It has been mostly involved in boundary sharpening during development, tissue regeneration and cancer. Developmental models of the understanding of pathology-related cell reprogramming are yet to be established. Here we comment on the recently discovered "Mixer Cells" undergoing highly stereotyped developmental reprogramming during Drosophila epidermal morphogenesis. The JNK signaling pathway, which is involved in regenerative cell reprogramming, is essential to Mixer Cell formation. Thus the Mixer Cell model may provide a link between developmental cell reprogramming and regeneration. PMID:... Fly journals http://www.medworm.com/rss/comments.php?id=4945789 Mon, 20 Jun 2011 09:30:11 +0100 4945789 http://www.medworm.com/index.php?rid=4945788&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21670603%26dopt%3DAbstract Authors: Yamaguchi S, Heisenberg M Visual behavior of insects has long been studied, but it is only recently that a wide variety of genetic tools has become available for its analysis. Perhaps the most basic visual behaviour is phototaxis, locomotion towards a source of light. It is known in many insects and has been studied for over a century but the neural network underlying it is little understood. We recently described in the fruit fly Drosophila how different photoreceptor types contribute to phototaxis. By blocking subsets of them we showed that at least four of the five types are involved. In this short review, we compare phototactic behaviour in fruit flies and other insects (especially honeybees), and discuss what is known about the underlying neural circuitry. : PMID: 21... Fly journals http://www.medworm.com/rss/comments.php?id=4945788 Mon, 20 Jun 2011 09:30:06 +0100 4945788 http://www.medworm.com/index.php?rid=4851037&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21558799%26dopt%3DAbstract Authors: Zur Lage PI, Simpson TI, Jarman A Much of developmental biology is concerned with the processes by which cells become committed to particular fates in a regulated fashion, whereas cell biology addresses, among other things, the variety of differentiated forms and functions that cells can acquire. One open question is how the regulators of the former process lead to attainment of the latter. 'High-level' regulators of cell fate specification include the proneural factors, which drive cells to commit as precursors in the sensory nervous system. Recent research has concentrated on the gene expression events downstream of proneural factor function. Here we summarise this research and describe our own research that has provided clear links between a proneural factor, atonal, and th... Fly journals http://www.medworm.com/rss/comments.php?id=4851037 Mon, 23 May 2011 01:15:06 +0100 4851037 http://www.medworm.com/index.php?rid=4797695&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21525789%26dopt%3DAbstract Authors: Ringo J, Sharon G, Segal D Commensal bacteria can induce sexual isolation between populations of Drosophila. This phenomenon has implications for speciation, and raises questions about its behavioral and developmental mechanisms, which are not yet known. In this Extra View, we discuss related work by others, bearing directly on these issues, and we speculate about how bacteria might influence fly behavior. There are many reports of interaction between Drosophila and their microbiota that significantly impacts mating preferences. Sexual isolation can be enhanced or reduced by altering the culture media, or the microbiota inhabiting those media. More dramatically, the endoparasite Wolbachia has induced strong mate preferences in some instances. While a sudden, ecologically induc... Fly journals http://www.medworm.com/rss/comments.php?id=4797695 Sun, 08 May 2011 11:15:19 +0100 4797695 http://www.medworm.com/index.php?rid=4797694&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21540638%26dopt%3DAbstract Authors: Valentine M, Collier S Planar cell polarity (PCP) describes the orientation of a cell within the plane of an epithelial cell layer. During tissue development, epithelial cells normally align their PCP so that they face in the same direction. This alignment allows cells to move in a common direction, or to generate structures with a common orientation. A classic system for studying the coordination of epithelial PCP is the developing Drosophila wing. The alignment of epithelial PCP during pupal wing development allows the production of an array of cell hairs that point towards the wing tip. Multiple studies have established that the Frizzled (Fz) PCP signaling pathway coordinates wing PCP. Recently, we have found that the same pathway also controls the formation of ridges on th... Fly journals http://www.medworm.com/rss/comments.php?id=4797694 Sun, 08 May 2011 11:15:09 +0100 4797694 http://www.medworm.com/index.php?rid=4632926&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21406967%26dopt%3DAbstract Authors: Bronstein R, Segal D Transcription is the first step through which the cell operates, via its repertoire of transcription complexes, to direct cellular functions and cellular identity by generating the cell-specific transcriptome. The modularity of the composition of constituents of these complexes allows the cell to delicately regulate its transcriptome. In a recent study we have examined the effects of reducing the levels of specific transcription co-factors on the function of two competing transcription complexes, namely CHIP-AP and CHIP-PNR which regulate development of cells in the thorax of Drosophila. We found that changing the availability of these co-factors can shift the balance between these complexes leading to transition from utilization of CHIP-AP to CHIP-PNR. Th... Fly journals http://www.medworm.com/rss/comments.php?id=4632926 Fri, 25 Mar 2011 20:23:41 +0100 4632926 http://www.medworm.com/index.php?rid=4632924&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21406968%26dopt%3DAbstract Authors: Ambegaokar SS, Jackson G The use of P element collections led to the discovery of unanticipated effects from common genetic background mutants white, brown, and rosy in our previously reported model of tauopathy that expresses full-length human tau in the fly eye, in which mutant rosy suppresses mutant white and brown worsening of tau-induced toxicity (Ambegaokar & Jackson, 2010, Genetics, v. 186, p. 435-42). Here we discuss further possible effects of mini-white and evidence for autophagy as a mediator of white enhancement of tau toxicity. PMID: 21406968 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=4632924 Fri, 25 Mar 2011 20:23:16 +0100 4632924 http://www.medworm.com/index.php?rid=4632922&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21406969%26dopt%3DAbstract Authors: Lund VK, Delotto Y, Delotto R We have assembled a molecular toolkit enabling the facile generation of C-terminal fluorescent protein fusion constructs for the construction of transgenic Drosophila lines in the form of a series of modified vectors for P-element transformation. These vectors contain one of a variety of fluorescent tags including GFP, mCherry, Venus, Cerulean, photoactivatable paGFP and the red-to-green photoconvertible protein Dendra and provide a range of options with respect to transcriptional regulation. The vectors have been extensively tested in vivo and can produce fluorescent chimeric proteins that are functional. PMID: 21406969 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=4632922 Fri, 25 Mar 2011 19:58:29 +0100 4632922 http://www.medworm.com/index.php?rid=4632919&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21406970%26dopt%3DAbstract Authors: Vuilleumier R, Affolter M, Pyrowolakis G Orchestration of spatial organization by signaling gradients - morphogen gradients - is a fundamental principle in animal development. Despite their importance in tissue patterning and growth, the exact mechanisms underlying the establishment and maintenance of morphogen gradients are poorly understood. Our recent work on BMP (bone morphogenetic protein) morphogen signaling during wing development identified a novel protein, Pentagone (Pent), as a critical regulator of morphogen activity. In the following, we discuss the properties of Pent and its role as a feed-back loop in morphogen gradient formation. PMID: 21406970 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=4632919 Fri, 25 Mar 2011 19:57:38 +0100 4632919 http://www.medworm.com/index.php?rid=4517082&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21339705%26dopt%3DAbstract Authors: Joyce EF, McKim KS During prophase of meiosis I, genetic recombination is initiated with a Spo11-dependent DNA double-strand break (DSB). Repair of these DSBs can generate crossovers, which become chiasmata and are important for the process of chromosome segregation. To ensure at least one chiasma per homologous pair of chromosomes, the number and distribution of crossovers is regulated. One system contributing to the distribution of crossovers is the pachytene checkpoint, which requires the conserved gene pch2 that encodes an AAA+ATPase family member. Pch2-dependent pachytene checkpoint function causes delays in pachytene progression when there are defects in processes required for crossover formation, such as mutations in DSB-repair genes and when there are defects in th... Fly journals http://www.medworm.com/rss/comments.php?id=4517082 Fri, 25 Feb 2011 03:30:22 +0100 4517082 http://www.medworm.com/index.php?rid=4517081&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21339706%26dopt%3DAbstract Authors: Georgiev P, Chlamydas S, Akhtar A Dosage compensation of X-linked genes is a phenomenon of concerted, chromosome-wide regulation of gene expression underpinned by sustained and tightly regulated histone modifications and chromatin remodeling, coupled with constrains of nuclear architecture. This elaborate process allows the accomplishment of regulated expression of genes on the single male X chromosome to levels comparable to those expressed from the two X chromosomes in females. The ribonucleoprotein Male Specific Lethal (MSL) complex is enriched on the male X chromosome and is intricately involved in this process in Drosophila melanogaster. In this review we discuss the recent advances that highlight the complexity lying behind regulation of gene expression by just two-fold.... Fly journals http://www.medworm.com/rss/comments.php?id=4517081 Fri, 25 Feb 2011 03:30:16 +0100 4517081 http://www.medworm.com/index.php?rid=4517076&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21339707%26dopt%3DAbstract Authors: Dobi KC, Metzger T, Baylies MK Myogenesis in Drosophila embryos requires fusion between Founder cells (FCs) and Fusion Competent myoblasts (FCMs) to form multinucleate myotubes. Myoblast fusion is well characterized in embryos, and many factors required for this process have been identified; however, a number of questions pertaining to the mechanisms of fusion remain and are challenging to answer in the embryo. We have developed a modified primary cell culture protocol to address these questions in vitro. Using this system, we determined the optimal time for examining fusion in culture and confirmed that known fusion proteins are expressed and localized as in embryos. Importantly, we disrupted the actin and microtubule networks with the drugs latrunculin B and nocodazole, resp... Fly journals http://www.medworm.com/rss/comments.php?id=4517076 Fri, 25 Feb 2011 03:30:11 +0100 4517076 http://www.medworm.com/index.php?rid=4517075&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21339708%26dopt%3DAbstract A "mesmer"izing new approach to site-directed mutagenesis in large transformation-ready constructs: Mutagenesis via serial small mismatch recombineering. Fly (Austin). 2011 Apr 1;5(2) Authors: Jacobs JS, Hong X, Eberl DF Creating designer mutations in large genes is a challenge. Size limitations imposed by site-directed mutagenesis (SDM), coupled with the paucity of unique restriction enzyme sites, make subsequent cloning of these constructs extremely difficult. "Mutagenesis via Serial Small Mismatch Recombineering" (MSSMR) combines sequential recombineering steps with SDM to create seamless, pre-specified mutations as small as a single base pair. We demonstrate the simultaneous cloning of wild type and mutant constructs of a > 30 kb gene directly into attB transformation ve... Fly journals http://www.medworm.com/rss/comments.php?id=4517075 Fri, 25 Feb 2011 03:30:06 +0100 4517075 http://www.medworm.com/index.php?rid=4459308&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21273815%26dopt%3DAbstract Authors: Delotto R The Toll receptor propagates the ventralizing signal designating dorsal/ventral cell fate in the Drosophila embryo. The application of live-imaging approaches to this classical developmental signaling pathway is yielding some surprising new insights into Toll receptor signaling. In addition to it's previously known plasma membrane localization, Toll is present in Rab5+ early endosomes. Dominant, constitutively active forms of Toll preferentially partition into endosomes. Blocking endocytosis locally prevents Toll from signaling suggesting that endocytosis is required for Toll to signal. Augmenting endocytosis increases Toll signaling. Both interventions alter the shape of the Dorsal gradient globally indicating an important role of endocytosis in fixing spatial infor... Fly journals http://www.medworm.com/rss/comments.php?id=4459308 Fri, 11 Feb 2011 00:30:12 +0100 4459308 http://www.medworm.com/index.php?rid=4459307&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21273816%26dopt%3DAbstract Authors: Lee MJ, Mondal A, Small C, Paddibhatla I, Kawaguchi A, Govind S While microarray experiments generate voluminous data, discerning trends that support an existing or alternative paradigm is challenging. To synergize hypothesis building and testing, we designed the Pathogen Associated Drosophila MicroArray (PADMA) database for easy retrieval and comparison of microarray results from immunity-related experiments (www.padmadatabase.org). PADMA also allows biologists to upload their microarray-results and compare it with datasets housed within PADMA. We tested PADMA using a preliminary dataset from Ganaspis xanthopoda-infected fly larvae, and uncovered unexpected trends in gene expression, reshaping our hypothesis. Thus, the PADMA database will be a useful resource to fly researche... Fly journals http://www.medworm.com/rss/comments.php?id=4459307 Fri, 11 Feb 2011 00:30:08 +0100 4459307 http://www.medworm.com/index.php?rid=4391280&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21245663%26dopt%3DAbstract Authors: Lawrence PA Scientists like to consider themselves as especially objective, but, however hard we try we cannot be very different from everyone else. Like them we helplessly absorb our knowledge, our perspectives, our valuation of whether something is exciting or boring from those around us. In this "extra view" I reflect on fashion, illustrating by a small discovery of ours, ( 1) and discussing why it was not made before. PMID: 21245663 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=4391280 Tue, 25 Jan 2011 02:00:29 +0100 4391280 http://www.medworm.com/index.php?rid=4391279&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21245664%26dopt%3DAbstract In this report, we further characterize lgl in this epithelium patterning and the morphogenetic changes of specified border cells. Genetic interactions of lgl with discs large (dlg) and scribble (scrib), another two nTSGs in specifying the PFC fate reveal a cooperative role of this group of genes. Meanwhile, we find that loss of lgl function causes failure of follicle cells at the anterior to differentiate properly. The clonal analysis further indicates that lgl is necessary not only for the border cell differentiation, but also for control of the collective border cell migration via presumably modulating the apico-basal polarity and cell adhesion. Overall, we identify Lgl as an essential factor in regulating differentiation and morphogenetic movement of the ovarian epithelial follicle cel... Fly journals http://www.medworm.com/rss/comments.php?id=4391279 Tue, 25 Jan 2011 02:00:16 +0100 4391279 http://www.medworm.com/index.php?rid=4391278&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21245665%26dopt%3DAbstract Authors: Cranna NJ, Mitchell NC, Hannan RD, Quinn LM Here we highlight our recent study, which revealed a mechanism critical for tight regulation of Drosophila myc (dmyc) transcription. Our previous work demonstrated that the RRM (RNA recognition motif) protein Half pint (Hfp) behaves as a growth and cell cycle inhibitor and work from D. Levens group has shown the mammalian ortholog, FIR (the FBP Interacting Repressor), is a tumour suppressor. Although RRM domain containing proteins such as Hfp and FIR have been ascribed splicing and transcriptional roles, our work suggests that Hfp is likely to achieve cell cycle inhibition via direct repression of dmyc transcription. We have demonstrated that Hfp binds to the dmyc promoter and is essential for repression of dmyc transcription, which ... Fly journals http://www.medworm.com/rss/comments.php?id=4391278 Tue, 25 Jan 2011 02:00:09 +0100 4391278 http://www.medworm.com/index.php?rid=4269668&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21150287%26dopt%3DAbstract Authors: Dimova DK Inactivation of the retinoblastoma protein (pRB) is a hallmark of human cancer. Accordingly the RB pathway has been extensively studied in mammals, flies and worms, but mostly in the context of cell cycle entry. The means by which RB proteins regulate differentiation and the transcription of genes involved in differentiation and development is less well understood. We have examined how Drosophila RB proteins regulate differentiation-specific genes in proliferating cells. We found that the mechanism of repression differs from what has been observed at cell cycle regulated genes (Figure 1). Two different chromatin modifications present at different locations contribute to the repression of such genes. We argue that this represents a novel mechanism of repression and th... Fly journals http://www.medworm.com/rss/comments.php?id=4269668 Mon, 20 Dec 2010 02:20:35 +0100 4269668 http://www.medworm.com/index.php?rid=4269667&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21150317%26dopt%3DAbstract Authors: Morton DB The ability to detect changes in oxygen concentration in the environment is critical to the survival of all animals. This requires cells to express a molecular oxygen sensor that can detect shifts in oxygen levels and transmit a signal that leads to the appropriate cellular response. Recent biochemical, genetic and behavioral studies have shown that the atypical soluble guanylyl cyclases function as oxygen detectors in Drosophila larvae triggering a behavioral escape response when exposed to hypoxia. These studies also identified the sensory neurons that innervate the terminal sensory cones as likely chemosensors that mediate this response. Here I summarize the data that led to these conclusions and also highlight evidence that suggests additional, as yet unidentifie... Fly journals http://www.medworm.com/rss/comments.php?id=4269667 Mon, 20 Dec 2010 02:20:25 +0100 4269667 http://www.medworm.com/index.php?rid=4269666&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21150318%26dopt%3DAbstract Authors: Evans IR, Wood W Drosophila embryonic hemocytes have emerged as a potent system to analyze the roles of key regulators of the actin and microtubule cytoskeletons live and in an in vivo context (see Table I and references therein). The relative ease with which live imaging can be used to visualize the invasive migrations of these highly motile macrophages and their responses to wound and chemoattractant signals make them a particularly appropriate and genetically tractable cell type to study in relation to pathological conditions such as cancer metastasis and inflammation. (1-3) In order to understand how signaling pathways are integrated for a coordinated response, a question with direct relevance to autoimmune dysfunction, we have sought to more fully characterize the inputs ... Fly journals http://www.medworm.com/rss/comments.php?id=4269666 Mon, 20 Dec 2010 02:20:17 +0100 4269666 http://www.medworm.com/index.php?rid=4146221&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21057214%26dopt%3DAbstract Authors: Schachter H, Boulianne GL N-glycans are post-translational modifications in which the sugar chain is covalently linked to protein by a GlcNacβ1-N-asparagine linkage. Drosophila melanogaster and other invertebrates, but not vertebrates, synthesize large amounts of "paucimannose" N-glycans that contain only 3 or 4 mannose residues. The enzyme UDP-GlcNac:α3-D-mannoside β1,2-N-acetylglucosaminyltransferase I (GnTI, encoded by the Mgat1 gene) controls the synthesis of paucimannose N-glycans. Either deletion or neuron-specific knockdown of Mgat1 in wild-type flies results in pronounced defects in locomotion, structural defects in the adult central nervous system and a severely reduced lifespan. We have recently shown that neuronal expression of a wild-type Mgat1 transgene in Mgat... Fly journals http://www.medworm.com/rss/comments.php?id=4146221 Wed, 10 Nov 2010 07:05:17 +0100 4146221 http://www.medworm.com/index.php?rid=4146220&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D21057219%26dopt%3DAbstract Authors: Suissa Y, Ordan E, Deshpande G, Gerlitz O During metazoan development, a small number of signaling pathways are iteratively used to orchestrate diverse rocesses such as cell division, cell fate specification and survival. Temporal and spatial regulation of these pathways underlies the final cellular makeup, size and shape of organs. In Drosophila melanogaster, the master switch gene Sex-lethal (Sxl) orchestrates all aspects of female development and behavior by modulating gene expression. Many of the sex-specific differences in gene expression and morphology are controlled through a gene activity cascade that involves Sxl→tra→dsx-fru. However, various aspects of somatic sexual development appear to be independent of this cascade. Consistent with this idea, Sxl protein, on ... Fly journals http://www.medworm.com/rss/comments.php?id=4146220 Wed, 10 Nov 2010 07:05:09 +0100 4146220 http://www.medworm.com/index.php?rid=3915350&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20798594%26dopt%3DAbstract Authors: Garbuzov A, Tatar M The steroid 20-hydroxy-ecdysone (20-HE ) and the sesquiterpenoid Juvenile Hormone (JH) coordinate insect life stage transitions. 20-HE exerts these effects by the sequential induction of response genes. In the nematode Caenorhabditis elegans hormones also play a role in such transitions, but notably, microRNA such as let-7 and lin-4 have likewise been found to help order developmental steps. Little is known about the corresponding function of homologous microRNA in Drosophila melanogaster, and the way microRNA might be regulated by 20-HE in the fly is ambiguous. Here we used Drosophila S2 cells to analyze the effects of 20-HE on D. melanogaster microRNA let-7 and miR-125, the homolog of lin-4. The induction by 20-HE of let-7 and miR-125 in S2 cells is inhib... Fly journals http://www.medworm.com/rss/comments.php?id=3915350 Tue, 31 Aug 2010 06:00:25 +0100 3915350 http://www.medworm.com/index.php?rid=3915347&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20798595%26dopt%3DAbstract Authors: Chatterjee A, Hardin PE Circadian clocks keep time in the digestive, circulatory, reproductive, excretory and nervous systems even in absence of external cues. Central oscillators in the brain control locomotor activity of organisms ranging from fruit flies to man, but the functions of the clocks in peripheral nervous system are not well understood. The presence of autonomous peripheral oscillators in the major taste organ of Drosophila, the proboscis, prompted us to test whether gustatory responses are under control of the circadian clock. We find that synchronous rhythms in physiological and behavioral responses to attractive and aversive tastants are driven by oscillators in gustatory receptor neurons (GRNs); primary sensory neurons that carry taste information from the pro... Fly journals http://www.medworm.com/rss/comments.php?id=3915347 Tue, 31 Aug 2010 06:00:22 +0100 3915347 http://www.medworm.com/index.php?rid=3915336&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20798602%26dopt%3DAbstract In this report, we demonstrate the effectiveness of M2(H37A)-mediated ablation as a new means to selectively eliminate cells of interest during Drosophila development. PMID: 20798602 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=3915336 Tue, 31 Aug 2010 06:00:17 +0100 3915336 http://www.medworm.com/index.php?rid=3915335&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20798603%26dopt%3DAbstract Authors: Lajeunesse D Scribbler was identified as a genetic modifier of the Drosophila tumor suppressor gene Merlin. Loss of Merlin results in hyperplasia in a number of different epithelial tissues including the wing and eye imaginal discs, however loss of scribbler does not. The lack of an overt proliferation sbb phenotype has complicated the mechanistic link between sbb and Merlin. Scribbler encodes two novel transcriptional repressors which function in numerous processes including axon guidance and pattern formation within the wing. While the two sbb isoforms have some redundant functions overexpression of two sbb isoforms within the wing show distinct and opposite effects. Overexpression of the smaller SbbA isoform results in a larger wing, while overexpression of larger SbbB isof... Fly journals http://www.medworm.com/rss/comments.php?id=3915335 Tue, 31 Aug 2010 06:00:14 +0100 3915335 http://www.medworm.com/index.php?rid=3915334&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20798604%26dopt%3DAbstract Authors: Papagiannouli F, Mechler BM Gamete development requires a coordinated soma-germ line interaction that ensures renewal and differentiation of germline and somatic stem cells. The physical contact between the germline and somatic cell populations is crucial because it allows the exchange of diffusible signals among them. The tumor suppressor gene discs large (dlg) encodes a septate junction protein with functions in epithelial cell polarity, asymmetric neuroblast division and formation of neuromuscular junctions. Our recent work reveals a new role of dlg in the Drosophila testis, as mutations in dlg lead to testis defects and cell death. Dlg is required throughout spermatogenesis in the somatic lineage and its localization changes from a uniform distribution along the plasma mem... Fly journals http://www.medworm.com/rss/comments.php?id=3915334 Tue, 31 Aug 2010 06:00:10 +0100 3915334 http://www.medworm.com/index.php?rid=3633386&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20519935%26dopt%3DAbstract Authors: Li LM, Arnosti DN The structure of chromatin in eukaryotes exerts significant influences on many DNA related processes, including transcription, replication, recombination and repair. A useful tool for mapping chromatin structure is micrococcal nuclease (MNase), which induces double-strand breaks within nucleosome linker regions, and with more extensive digestion, single-strand nicks within the nucleosome itself. Many studies, carried out largely with microbes and cell cultures, have used MNase to determine the positions of nucleosomes within a region of DNA to identify dynamic changes induced during gene regulation. To measure similar processes in a developmental context, we turned to a tractable model system, the Drosophila embryo. Here we describe a protocol that enables MN... Fly journals http://www.medworm.com/rss/comments.php?id=3633386 Sun, 06 Jun 2010 14:54:07 +0100 3633386 http://www.medworm.com/index.php?rid=3596390&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20495356%26dopt%3DAbstract Authors: Bryson TD, Weber CM, Henikoff S The expression and genome-wide mapping of epitope-tagged DNA- and chromatin-binding proteins in cultured cells has become a powerful strategy for epigenome characterization, especially in Drosophila, where cell lines derived from numerous tissues are now available. However this strategy relies on establishing transfected cell lines, which is time-consuming and introduces variability. Here we show that baculovirus-encoded proteins can be efficiently produced following infection of Drosophila cell lines of different types. Using chromatin affinity purification, we show that epitope-tagged proteins produced in baculovirus-infected cells provide genome-wide profiles of the histone variant H2Av that are comparable to those produced by plasmid-transfe... Fly journals http://www.medworm.com/rss/comments.php?id=3596390 Wed, 26 May 2010 08:27:17 +0100 3596390 http://www.medworm.com/index.php?rid=3596389&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20495357%26dopt%3DAbstract Authors: Bitan A, Guild GM, Abdu U Microtubules (MTs) are polar polymers that can facilitate asymmetric distribution of cell components, a process important for polarized cell growth. The highly elongated and polarized Drosophila mechnosensory bristle cytoplasm is filled with short MTs that constitute a significant component of the shaft cytoplasm. Inhibition of MT assembly affects biased axial growth in the bristle and highlights the importance of MTs for this process. We demonstrate that the vast majority of bristle MTs are organized in a polarized manner, minus-ends out. We also show that genetic disruption of the MT polarity affects the polar distribution of cell components and leads to an alteration in the biased axial shape of the bristle shaft. Thus, we suggest that the asymmetr... Fly journals http://www.medworm.com/rss/comments.php?id=3596389 Wed, 26 May 2010 08:27:14 +0100 3596389 http://www.medworm.com/index.php?rid=3596388&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20495386%26dopt%3DAbstract Authors: Umetsu D, Dahmann C The subdivision of proliferating tissues into groups of non-intermingling sets of cells, termed compartments, is a common process of animal development. Signaling between adjacent compartments induces the local expression of morphogens that pattern the surrounding tissue. Sharp and straight boundaries between compartments stabilize the source of such morphogens during tissue growth and, thus, are of crucial importance for pattern formation. Signaling pathways required to maintain compartment boundaries have been identified, yet the physical mechanisms that maintain compartment boundaries remained elusive. Recent data now show that a local increase in actomyosin-based mechanical tension on cell bonds is vital for maintaining compartment boundaries in Drosoph... Fly journals http://www.medworm.com/rss/comments.php?id=3596388 Wed, 26 May 2010 08:27:10 +0100 3596388 http://www.medworm.com/index.php?rid=3399435&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20305396%26dopt%3DAbstract Authors: Zhou S, Mackay TF, Anholt RR Accurate perception of chemical signals from the environment is critical for the fitness of most animals. Drosophila melanogaster experiences its chemical environment through families of chemoreceptors that include olfactory receptors, gustatory receptors and odorant binding proteins. Its chemical environment, however, changes during its life cycle and the interpretation of chemical signals is dependent on dynamic social and physical surroundings. Phenotypic plasticity of gene expression of the chemoreceptor repertoire allows flies to adjust the chemosensory window through which they "view" their world and to modify the ensemble of expressed chemoreceptor proteins in line with their developmental and physiological state and according to their needs... Fly journals http://www.medworm.com/rss/comments.php?id=3399435 Wed, 24 Mar 2010 20:08:06 +0100 3399435 http://www.medworm.com/index.php?rid=3361067&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20224294%26dopt%3DAbstract Authors: Morata G, Herrera SC We have generated wing disc compartments that contain marked fast growing M(+) clones surrounded by slow dividing M/+ cells. Under these conditions the interactions between fast and slow dividing cells at the clone borders frequently lead to cell competition. However, our assay suppressing apoptosis indicates that cell competition plays no major role in size control. We argue that cells within a compartment proliferate according to their genotype independently of each other and that their contribution to the final structure will depend solely on their proliferation rate. This model is supported by a computer simulation that predicts values similar to those found experimentally. Our results on the growth of M(+) clones within compartments and on the express... Fly journals http://www.medworm.com/rss/comments.php?id=3361067 Sat, 13 Mar 2010 14:50:06 +0100 3361067 http://www.medworm.com/index.php?rid=3353984&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20215860%26dopt%3DAbstract Authors: Brook WJ A key event in fly limb development is the binary subdivision of the cardinal axes of imaginal discs by selector genes.(1-3) As an example, all limbs are partitioned into anterior and posterior compartments through the expression of engrailed (en) in posterior cells of imaginal discs and en expression is both necessary and sufficient to direct posterior instead of default anterior development.(4-8) In the leg imaginal disc, posterior en-expressing cells secrete the ligand Hedgehog (Hh), which in turn activates ventral Wingless (Wg) expression and dorsal Decapentaplegic (Dpp) expression in domains that bisect the imaginal disc.(9,10) Dpp and Wg act in concert to specify distal fates by inducing the expression of downstream genes including the selector gene Distal-less,... Fly journals http://www.medworm.com/rss/comments.php?id=3353984 Thu, 11 Mar 2010 17:56:15 +0100 3353984 http://www.medworm.com/index.php?rid=3353983&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20215870%26dopt%3DAbstract Authors: Gilsohn E, Volk T The formation of complex tissues requires the assembly of distinct cell types that often migrate over long distances in order to interact with each other and establish a functional tissue. The establishment of the contractile tissue in the Drosophila embryo has been used as a model system in which to study how the interplay between distinct cell types results in a complex, functioning tissue. The Drosophila contractile tissue is composed of multi-nucleated muscle cells that are attached to individual specialized ectodermal cells, named tendon cells, at each end. The tendon cells are anchored to the cuticle external skeleton on their apical side and form integrin-dependent myotendinous junctions at their basal end. In order for the complex muscle-pattern to fo... Fly journals http://www.medworm.com/rss/comments.php?id=3353983 Thu, 11 Mar 2010 17:56:12 +0100 3353983 http://www.medworm.com/index.php?rid=3353982&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20215872%26dopt%3DAbstract Authors: Jepson JE, Reenan RA In metazoan cells, transcripts that fold into double-strand RNA structures are endowed with the capacity to undergo A-to-I RNA editing, during which adenosines are catalytically deaminated to inosines by a class of enzymes known as ADARs (adenosine deaminases acting on RNA). In Drosophila, a wide range of coding mRNAs associated with signaling in the nervous system undergo A-to-I editing, and loss of editing results in extreme behavioral defects. Furthermore, there are indications that the precursors of endogenous small interfering RNAs also undergo editing. However, the mechanism by which A-to-I editing is related to ethology in Drosophila is unclear, as are the precise cell-types and developmental stages in which editing is most crucial. We have investig... Fly journals http://www.medworm.com/rss/comments.php?id=3353982 Thu, 11 Mar 2010 17:56:07 +0100 3353982 http://www.medworm.com/index.php?rid=3186161&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20081354%26dopt%3DAbstract We reported vast differences in the molar concentrations of endogenous effectors of Hh signaling, with Smo present in limiting concentrations.(5) This extra view summarizes the implications of this endogenous ratio in relation to current models of Hh signaling and places our results in the context of recent work describing the involvement of guanine nucleotide binding protein Galphai and Cos2 motility. PMID: 20081354 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=3186161 Wed, 20 Jan 2010 06:42:11 +0100 3186161 http://www.medworm.com/index.php?rid=3186160&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20081356%26dopt%3DAbstract Authors: Gildor B, Massarwa R, Shilo BZ, Schejter ED In Drosophila embryos, muscle fiber formation via myoblast fusion relies on essential contributions made by the conserved Arp2/3 microfilament nucleation machinery. Two key nucleation promoting factors (NPFs), SCAR and WASp, have been shown to mediate this aspect of Arp2/3 function. We have used these unique circumstances, to study the requirements and coordination of distinct NPF activities, within a common developmental setting. Our results suggest that, although operating within close spatial and temporal proximity, the two regulators of actin polymerization are used in a step-wise manner and perform separate functional roles. Our approach also allows us to assess the involvement of the Arp2/3 machinery in formation of a distinct,... Fly journals http://www.medworm.com/rss/comments.php?id=3186160 Wed, 20 Jan 2010 06:42:08 +0100 3186160 http://www.medworm.com/index.php?rid=3186159&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20081362%26dopt%3DAbstract Authors: Witsell A, Kane DP, McVey M Over the past two decades, a large collection of transposable elements inserted at various locations in the Drosophila melanogaster genome has been assembled. These transposons are frequently utilized in imprecise excision screens to generate deletions in genes of interest. In general, these screens involve genetic manipulations to combine a non-autonomous transposon and the appropriate transposase in individual male or female flies. DNA double-strand breaks are created via transposase action in both somatic and germline cells of these individuals and inaccurate repair events are recovered in the progeny. Because deletion-prone repair of transposon-induced double-strand breaks is rare, these screens generally require a significant investment of time... Fly journals http://www.medworm.com/rss/comments.php?id=3186159 Wed, 20 Jan 2010 06:42:06 +0100 3186159 http://www.medworm.com/index.php?rid=3105317&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D20009510%26dopt%3DAbstract Authors: Künnapuu J, Shimmi O Decapentaplegic (DPP) and bone morphogenetic protein (BMP)-2 and -4 type ligands form a branch of the transforming growth factor-beta (TGFbeta) superfamily. They play prominent roles in metazoan developmental processes as diverse as cell proliferation, apoptosis, differentiation and cell-fate determination. Maturation of the BMP2/4/DPP type proteins requires proteolytic cleavage of their proproteins by furin-type proprotein convertases (PCs). Even though cleavage of the prodomain is critical for signaling, much less attention has been paid to the role of proteolytic processing. Our studies suggest that the cleavage sites of BMP2/4/DPP type proteins have been diversified and can be categorized into at least four different types. These findings indicate... Fly journals http://www.medworm.com/rss/comments.php?id=3105317 Sat, 19 Dec 2009 17:06:05 +0100 3105317 http://www.medworm.com/index.php?rid=3057150&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19955851%26dopt%3DAbstract Authors: Artieri CG, Singh RS Developmental geneticists have spearheaded the synthesis of evolutionary and developmental biology, a.k.a 'evo-devo', leading to a wealth of recent insights about how morphological diversity has evolved. However, there exists a gap between these disciplines, and evo-devo has not benefited from an integration of the principles derived from population genetics and molecular evolution. In order to contribute to the remediation of this deficiency, we recently performed a study investigating how genes diverge among closely related species of Drosophila as a function of when they are expressed during development. We found that patterns of genetic divergence parallels morphology: interspecific divergence accumulates as development progresses. We also sought to te... Fly journals http://www.medworm.com/rss/comments.php?id=3057150 Fri, 04 Dec 2009 21:06:04 +0100 3057150 http://www.medworm.com/index.php?rid=3031282&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19934653%26dopt%3DAbstract Authors: Ninov N, Martín-Blanco E Although the molecular elements controlling cell cycle progression are well established, the mechanisms regulating how cell proliferation is triggered in response to extrinsic stimuli and how cell divisions change speed, particularly in stem or tumor cells or regenerative tissues, are poorly understood. One exceptional model system in which these events are precisely defined is Drosophila abdominal morphogenesis, in which stem-like histoblasts build the adult epidermis at metamorphosis by undergoing a series of sequential transitions from a non-proliferative to a growing, and finally to an invasive epithelium. We have recently uncovered in histoblasts an internal logic modulating cell cycle transitions that should constitute a reference paradigm f... Fly journals http://www.medworm.com/rss/comments.php?id=3031282 Tue, 27 Oct 2009 00:00:00 +0100 3031282 http://www.medworm.com/index.php?rid=3015609&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19923919%26dopt%3DAbstract Authors: Sheng XR, Matunis EL The reversal of cellular differentiation, or dedifferentiation, has fascinated biologists for many decades. While cells can be re-programmed extensively in culture, examples of in vivo dedifferentiation have recently emerged in both vertebrate and invertebrate systems, allowing for analysis of this intriguing process under more physiologically relevant conditions. Studies suggest that dedifferentiation occurs not only during large-scale cellular regeneration, but also at low levels to replenish stem cells lost due to normal turnover. Our recent paper demonstrates a novel method to induce the dedifferentiation of lineage-committed stem cell daughters back into germline stem cells (GSCs) in the Drosophila testis. We also show a requirement for activation of ... Fly journals http://www.medworm.com/rss/comments.php?id=3015609 Sun, 25 Oct 2009 00:00:00 +0100 3015609 http://www.medworm.com/index.php?rid=2990099&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19901536%26dopt%3DAbstract Authors: Furukubo-Tokunaga K, Adachi Y, Kurusu M, Walldorf U The Drosophila Pax6 genes, eyeless (ey) and twin of eyeless (toy), are expressed in both eyes and the brain. Previous studies have demonstrated that ey plays important roles in axonal outgrowth and differentiation of mushroom bodies (MBs), which are centers for associative learning and memory in flies. However, the functional significance of toy in brain development is poorly understood. Here, we describe the expression patterns of TOY, and show that TOY expression partially overlaps with EY expression in the embryonic, larval and adult brains. Mutations of toy perturb brain neuromere formation in the embryonic stages, and result in severe deformation of the MB lobes in pharate adult brains. Moreover, we also analyzed toy fun... Fly journals http://www.medworm.com/rss/comments.php?id=2990099 Wed, 21 Oct 2009 00:00:00 +0100 2990099 http://www.medworm.com/index.php?rid=2990098&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19901548%26dopt%3DAbstract Authors: Gómez FH, Defays R, Sambucetti P, Scannapieco AC, Loeschcke V, Norry FM Starvation resistance (SR) is an important trait for survival of insects in the wild. We used recombinant inbred lines (RIL) to search for quantitative trait loci (QTL) in crosses between intercontinental inbred lines that were originally selected for heat-knockdown resistance. SR was measured as the time of survival under repeated events of starvation. SR was consistently higher in females than in males. Composite interval mapping identified one QTL region (cytological range 64D-66E2) on the left arm of chromosome 3 in males, and no QTL was found in females. Many candidate genes that were identified in previous studies of QTL for stress resistance are included within this QTL region. The QTL-allele t... Fly journals http://www.medworm.com/rss/comments.php?id=2990098 Wed, 21 Oct 2009 00:00:00 +0100 2990098 http://www.medworm.com/index.php?rid=2804740&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19755840%26dopt%3DAbstract Authors: Draper I, Tabaka ME, Jackson FR, Salomon RN, Kopin AS The Drosophila smooth gene encodes an RNA binding protein that has been well conserved through evolution. To investigate the pleiotropic functions mediated by the smooth gene, we have selected and characterized two sm mutants, which are viable as adults yet display robust phenotypes (including a significant decrease in lifespan). Utilizing these mutants, we have made the novel observation that disruption of the smooth/CG9218 locus leads to age-dependent muscle degeneration, and motor dysfunction. Histological characterization of adult sm mutants revealed marked abnormalities in the major thoracic tubular muscle: the tergal depressor of the trochanter (TDT). Corresponding defects include extensive loss/disruption of striatio... Fly journals http://www.medworm.com/rss/comments.php?id=2804740 Fri, 18 Sep 2009 02:50:04 +0100 2804740 http://www.medworm.com/index.php?rid=2720116&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19690461%26dopt%3DAbstract Authors: Johansen J, Johansen KM A spindle matrix has long been proposed to provide structural support for counterbalancing force production and a substrate for essential mitotic factors. For years the molecular identity of such a structure remained elusive. Recently a complex of nuclear proteins that reorganize into a spindle-like structure during prophase through metaphase that shows characteristics of a spindle matrix has been identified in Drosophila. We review how these results support the concept of a spindle matrix and discuss its possible function(s) during mitosis. Importantly, these molecules also appear to play critical roles during interphase in nuclear organization and function. Given that during cell division the entire nucleus undergoes a dynamic and tightly orchestrated... Fly journals http://www.medworm.com/rss/comments.php?id=2720116 Fri, 21 Aug 2009 13:40:04 +0100 2720116 http://www.medworm.com/index.php?rid=2640038&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19625763%26dopt%3DAbstract Neurogenetics and the "fly-stampede": Dissecting neural circuits involved in visual behaviors. Fly (Austin). 2009 Jul 27;3(3) Authors: Zhu Y, Frye M PMID: 19625763 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=2640038 Sun, 26 Jul 2009 17:54:06 +0100 2640038 http://www.medworm.com/index.php?rid=2640037&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19625773%26dopt%3DAbstract Authors: Hirano M, Neff D, Collier S The development of denticle rows on the ventral Drosophila embryo is a valuable system for studying the genetic control of epithelial patterning. During late embryogenesis, the apical surfaces of denticle-producing cells acquire a distinctive rectangular morphology with long anteroposterior boundaries, along which the denticles form, and short ventrolateral boundaries that stain strongly for adherens junction proteins. We observe that ventrolateral denticle cell boundaries are also convoluted, suggesting that the strong adherens staining results, at least in part, from the additional membrane in these regions. Embryos mutant for the Planar Cell Polarity (PCP) Effector gene multiple wing hairs (mwh), or expressing dominant negative form of the small ... Fly journals http://www.medworm.com/rss/comments.php?id=2640037 Sun, 26 Jul 2009 17:54:04 +0100 2640037 http://www.medworm.com/index.php?rid=2546324&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19556850%26dopt%3DAbstract Authors: Mundiyanapurath S, Chan YB, Leung AK, Kravitz EA Previous studies in Drosophila have demonstrated that whether flies fight like males or females can be switched by selectively manipulating genes of the sex determination hierarchy in male and female nervous systems. Here we extend these studies by demonstrating that changing the sex of cholinergic neurons in male fruit fly nervous systems via expression of the transformer gene increases the levels of aggression shown by the flies without altering the way the flies fight. Transformer manipulation in this way does not change phototaxis, geotaxis, locomotion or odor avoidance of the mutant males compared to controls. Cholinergic neurons must be feminized via this route during the late larval/early pupal stages of development to sh... Fly journals http://www.medworm.com/rss/comments.php?id=2546324 Sun, 28 Jun 2009 03:41:06 +0100 2546324 http://www.medworm.com/index.php?rid=2546323&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19556851%26dopt%3DAbstract Authors: Iwasaki S, Tomari Y microRNAs (miRNAs) downregulate the expression of their target genes by inducing translational repression and/or mRNA decay. Under specific conditions, miRNAs can even activate translation of their target mRNAs. These processes occur via miRNA-protein complexes, or RNA-induced silencing complexes (RISCs), which contain Argonaute (Ago) subfamily protein as a core component. However, detailed mechanisms of miRNA-mediated translational regulation remain unclear. We recently reported that, in Drosophila, both of the two Ago proteins, Ago1 and Ago2, can repress translation of the target mRNAs, but by remarkably different mechanisms. Furthermore, we here show that Ago2, but not Ago1, can activate translation of the target mRNAs when they lack the poly(A) tail, su... Fly journals http://www.medworm.com/rss/comments.php?id=2546323 Sun, 28 Jun 2009 03:41:04 +0100 2546323 http://www.medworm.com/index.php?rid=2224574&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19242103%26dopt%3DAbstract Authors: Farkaš R, Kováčiková M, Liszeková D, Beňo M, Daniš P, Rabinow L, Chase BA, Raška I Members of the highly conserved LAMMER family of protein kinases have been described in all eukaryotes. LAMMER kinases possess markedly similar peptide motifs in their kinase catalytic subdomains that are responsible for phosphotransfer and substrate interaction, suggesting that family members serve similar functions in widely diverged species. This hypothesis is supported by their phosphorylation of SR and SR-related proteins in diverged species. Here we describe a 3-dimensional homology model of the catalytic domain of DOA, a representative LAMMER kinase, encoded by the Drosophila locus Darkener of apricot (Doa). Homology modeling of DOA based on a ... Fly journals http://www.medworm.com/rss/comments.php?id=2224574 Sun, 01 Mar 2009 11:46:18 +0100 2224574 http://www.medworm.com/index.php?rid=2224573&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19242110%26dopt%3DAbstract Authors: Kuijper B, Morrow EH One basic condition of postmating sexual selection is that females mate more than once before fertilizing their ova. Knowledge of the frequency and extent of multiple mating in a given population or species is therefore important in order to fully understand the potential for sexual selection, in the form of sperm competition, sexual conflict and cryptic female choice. Surprisingly, there are only a handful of studies that have attempted to estimate the frequency of multiple mating in insects (including Drosophila) and none have made direct observations over extended periods of time. Here we use time-lapse photography to directly score matings in isolated pairs of D. melanogaster and show that multiple mating in the laboratory occurs at a high frequency bu... Fly journals http://www.medworm.com/rss/comments.php?id=2224573 Sun, 01 Mar 2009 11:46:12 +0100 2224573 http://www.medworm.com/index.php?rid=2224572&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19242114%26dopt%3DAbstract In this study we examine the fitness consequences of immune challenge in female Drosophila melanogaster by examining both direct (within generation) and indirect (between generations) costs and benefits of immune challenge. Though passing immunity to offspring has been studied in mammals for many years, only recently have researchers found evidence for a cross-generational priming response in invertebrates. By examining both potential fitness costs and benefits in the next generation, we were able to determine what effect immune challenge has on fitness. In agreement with other studies, we found a direct cost to infection, where immune challenged females laid fewer eggs than unchallenged females in two of the three lines we examined. In addition, we found some evidence for indirect costs. ... Fly journals http://www.medworm.com/rss/comments.php?id=2224572 Sun, 01 Mar 2009 11:46:06 +0100 2224572 http://www.medworm.com/index.php?rid=2224570&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19242123%26dopt%3DAbstract Authors: Specchia V, Bozzetti MP The crystal-Stellate system is one of the best-known examples of heterochromatin-euchromatin interaction. The components of this system are homologous repetitive sequences clustered in three regions: 12E1 and h27 on the X and h11 on the Y. The symptom of a disrupted crystal-Stellate interaction is the presence of crystals in the spermatocytes of males lacking the crystal region. Stellate silencing is based on the RNAi process. Many modifiers of this system have been isolated and many of these are involved in RNAi. One of these modifiers is aubergine(sting); this is a "gain of function" allele in somatic tissues. Here we report the different behavior of two aubergine alleles with respect to the RNAi pathway: aub(sting) and a "loss of function" heteroalle... Fly journals http://www.medworm.com/rss/comments.php?id=2224570 Sun, 01 Mar 2009 11:45:59 +0100 2224570 http://www.medworm.com/index.php?rid=2130116&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19164943%26dopt%3DAbstract Authors: Pitman JL, Dasgupta S, Krashes MJ, Leung B, Perrat PN, Waddell S A biological understanding of memory remains one of the great quests of neuroscience. For over 30 years the fruit fly Drosophila melanogaster has primarily been viewed as an excellent vehicle to find 'memory genes'. However, the recent advent of sophisticated genetic tools to manipulate neural activity has meant that these genes can now be viewed within the context of functioning neural circuits. A holistic understanding of memory in flies is therefore now a realistic goal. Larvae and adult flies exhibit remarkable behavioral complexity and they can both be trained in a number of ways. In this review, our intention is to summarize the many assays that have been developed to study plastic behaviors in flies. More ... Fly journals http://www.medworm.com/rss/comments.php?id=2130116 Sat, 24 Jan 2009 17:25:10 +0100 2130116 http://www.medworm.com/index.php?rid=2130117&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19164940%26dopt%3DAbstract Authors: Buch S, Pankratz MJ Physiology and behavior have historically been treated as separate subjects in the study of Drosophila. The latter is mentioned mainly in the context of neurobiology, while the former has been considered to take in studies of metabolism, cell biology and anatomy, among others. Of late, the line distinguishing physiology and behavior has become thinner, and this is exceptionally apparent in recent studies of nutrient signaling and of the regulation of feeding. This review represents a brief examination of the nexus between these intersecting fields of research in Drosophila. Other recently published reviews(1,2) serve as complements to this one. PMID: 19164940 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=2130117 Thu, 08 Jan 2009 05:00:00 +0100 2130117 http://www.medworm.com/index.php?rid=2130114&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19164949%26dopt%3DAbstract Authors: Zhang L, Yue T, Jiang J Initially discovered in Drosophila, the Hippo (Hpo) pathway has been recognized as a conserved signaling pathway that controls organ size during development by restricting cell growth and proliferation and by promoting apoptosis. In addition, abnormal activities of several Hpo pathway components have been implicated in human cancer. Here, we review the current understanding of the molecular and cellular basis of Hpo signaling in development and tumorigenesis, and discuss how the Hpo pathway integrates spatial and temporal signals to control tissue growth and organ size. PMID: 19164949 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=2130114 Wed, 07 Jan 2009 05:00:00 +0100 2130114 http://www.medworm.com/index.php?rid=2130118&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19164936%26dopt%3DAbstract Authors: Bell AJ, McBride SM, Dockendorff TC Development of a drug and its safe therapeutic application necessitates using animal models for testing purposes. While testing with mammalian models is essential prior to approval for human trials, the use of invertebrate animal models that are amenable to molecular genetic manipulations provide experimental and biological advantages that can streamline the discovery and testing process. Among the benefits of a genetics-based approach is the ability to screen for genes/proteins that may be novel drug targets, and the expedited development of genetic backgrounds that more accurately reflect a specific disease state. An invertebrate model may provide a more robust phenotype for screening, a situation that may arise when there is unanticipated... Fly journals http://www.medworm.com/rss/comments.php?id=2130118 Tue, 06 Jan 2009 05:00:00 +0100 2130118 http://www.medworm.com/index.php?rid=2130115&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19164947%26dopt%3DAbstract Authors: Tang H The melanization reaction, involving the synthesis of melanin to encapsulate pathogens, is a prominent immune response in Drosophila, the mosquito and other insects and arthropods. Biochemical studies with large insects have defined a basic model for how melanization is activated and regulated upon microbial infection. In this model, recognition of a microorganism triggers a serine protease cascade that activates phenol oxidase (PO), a key enzyme in the melanin biosynthetic pathway, and serpin-type protease inhibitors are involved in inhibiting the cascade. In the past few years, genetic studies in Drosophila have identified serine proteases and serpins that regulate activation of PO and melanization in vivo. These studies, along with molecular genetic analysis of melan... Fly journals http://www.medworm.com/rss/comments.php?id=2130115 Fri, 02 Jan 2009 05:00:00 +0100 2130115 http://www.medworm.com/index.php?rid=2102476&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19139635%26dopt%3DAbstract Authors: Rosenfeld JR, Desalle R, Lee EK, O'Grady P The Drosophila 12 genome data set was used to construct whole genome, gene family presence/absence matrices using a broad range of E value cutoffs as criteria for gene family inclusion. The various matrices generated behave differently in phylogenetic analyses as a function of the e-value employed. Based on an optimality criterion that maximizes internal corroboration of information, we show that values of e(-105) to e(-125) extract the most internally consistent phylogenetic signal. Functional class of most genes and gene families can be accurately determined based on the D. melanogaster genome annotation. We used the gene ontology (GO) system to create partitions based on gene function. Several measures of phylogenetic congruence (d... Fly journals http://www.medworm.com/rss/comments.php?id=2102476 Mon, 24 Nov 2008 05:00:00 +0100 2102476 http://www.medworm.com/index.php?rid=2043244&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19077541%26dopt%3DAbstract Authors: McElroy JM, McLean RA, McLean JR PMID: 19077541 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=2043244 Sun, 23 Nov 2008 05:00:00 +0100 2043244 http://www.medworm.com/index.php?rid=2043243&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19077544%26dopt%3DAbstract Authors: Rodríguez I, Baena-Lopez LA, Baonza A The function of the conserved Drosophila Hippo signaling pathway has been shown to be required to limit cell proliferation. Several studies have identified different target genes of this pathway that could modulate this function. However, the ectopic expression of these genes cannot account for all of the hyperplasic and pattern defects displayed by Hippo signaling mutants. We have recently identified two new targets of the Hippo pathway, the heparan sulfate proteoglycans (HSPGs) encoded by division abnormally delayed (dally) and dally-like protein (dlp). The function of these glypicans is required to modulate the activity of different signaling pathways triggered by diffusible ligands. Thus, our results link the function of the Hippo... Fly journals http://www.medworm.com/rss/comments.php?id=2043243 Fri, 21 Nov 2008 05:00:00 +0100 2043243 http://www.medworm.com/index.php?rid=1993810&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D19029797%26dopt%3DAbstract Authors: Vanzomeren-Dohm A, Flannery E, Duman-Scheel M Protocols for both generation of mosaic clones and whole-mount in situ hybridization detection of mRNA have led to an advanced understanding of Drosophila development. A simple means of combining these techniques for staining of imaginal discs would be useful, as it would allow for analysis of mRNA transcripts in marked mosaic clones. However, few researchers attempt such experiments due to the technical difficulty of simultaneously detecting clones and mRNA transcripts. Furthermore, maintaining the ability to use GFP-marked clones is desirable. However, typical Drosophila in situ hybridization protocols result in loss of GFP fluorescence. The method for double labeling of imaginal discs described here maintains the ability to iden... Fly journals http://www.medworm.com/rss/comments.php?id=1993810 Fri, 21 Nov 2008 05:00:00 +0100 1993810 http://www.medworm.com/index.php?rid=1818955&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18806473%26dopt%3DAbstract Authors: Sheeley SL, McAllister BF Similar outcomes are often observed in species exposed to similar selective regimes, but it is unclear how often the same mechanism of adaptive evolution is followed. Here we present an analysis of selection affecting sequence variation in the Alcohol dehydrogenase (Adh) gene of Drosophila americana, a species endemic to a large climate range that has been colonized by D. melanogaster. Unlike D. melanogaster, there is no evidence of selection on allozymes of ADH across the sampled range. This indicates that if there has been a similar adaptive response to climate in D. americana, it is not within the coding region of Adh. Instead, analyses of a combined dataset containing 86 alleles of Adh reveal purifying selection on the Adh gene, especially within ... Fly journals http://www.medworm.com/rss/comments.php?id=1818955 Wed, 24 Sep 2008 00:50:26 +0100 1818955 http://www.medworm.com/index.php?rid=1757544&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18719407%26dopt%3DAbstract Authors: Park Y, Zhang Z, Linhardt RJ, Lemosy EK Spatial information embedded in the extracellular matrix establishes the dorsoventral polarity of the Drosophila embryo through the ventral activity of a serine protease cascade. Pipe is a Golgi-localized protein responsible for generating this spatial information during oogenesis through sulfation of unknown glycans. Although Pipe has sequence homology to glycosaminoglycan 2-O-sulfotransferases, its activity and authentic substrates have not been demonstrated and genetic evidence has argued against a role for glycosaminoglycans in dorsoventral polarity establishment. Here, direct examination of matrix glycosaminoglycans demonstrates that pipe-mutant matrix shows decreased tri-sulfated heparan sulfate compared to wild-type matrix, with c... Fly journals http://www.medworm.com/rss/comments.php?id=1757544 Thu, 31 Jul 2008 04:00:00 +0100 1757544 http://www.medworm.com/index.php?rid=1757546&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18719405%26dopt%3DAbstract Authors: Kyriakakis P, Tipping M, Abed L, Veraksa A Tandem affinity purification (TAP) has been widely used for the analysis of protein complexes. We investigated the parameters of the recently developed TAP method (GS-TAP) and its application in Drosophila. This new tag combination includes two Protein G modules and a streptavidin binding peptide (SBP), separated by one or two TEV protease cleavage sites. We made pMK33-based GS-TAP vectors to allow for generation of stable cell lines using hygromycin selection and inducible expression from a metallothionein promoter, as well as pUAST-based vectors that can be used for inducible expression in flies. Rescue experiments in flies demonstrated that the GS-TAP tag preserves the function of the tagged protein. We have done parallel purificat... Fly journals http://www.medworm.com/rss/comments.php?id=1757546 Thu, 24 Jul 2008 04:00:00 +0100 1757546 http://www.medworm.com/index.php?rid=1757548&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18719403%26dopt%3DAbstract Authors: Bannan BA, Van Etten J, Kohler JA, Tsoi Y, Hansen NM, Sigmon S, Fowler E, Buff H, Williams TS, Ault JG, Glaser RL, Korey CA Palmitoylation is the post-translational addition of a palmitate moiety to a cysteine residue through a covalent thioester bond. The addition and removal of this modification is controlled by both palmitoyl acyl-transferases and thioesterases. Using bioinformatic analysis, we identified 22 DHHC family palmitoyl acyl-transferase homologs in the Drosophila genome. We used in situ hybridization, RT-PCR, and published FlyAtlas microarray data to characterize the expression patterns of all 22 fly homologs. Our results indicate that all are expressed genes, but several, including CG1407, CG4676, CG5620, CG6017/dHIP14, CG6618, CG6627 and CG17257 appear to be enr... Fly journals http://www.medworm.com/rss/comments.php?id=1757548 Tue, 15 Jul 2008 04:00:00 +0100 1757548 http://www.medworm.com/index.php?rid=1757545&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18719406%26dopt%3DAbstract Authors: Parkash R, Kalra B, Sharma V We investigated within as well as between population variability in desiccation resistance, cuticular lipid mass per fly and cuticular water loss in nine geographical populations of a tropical drosophilid, Zaprionus indianus. Interestingly, the amount of cuticular lipids and desiccation resistance in this non-melanic species are significantly higher as compared with melanic Drosophila melanogaster. On the basis of isofemale line analysis, within population trait variability in cuticular lipid mass per fly is positively correlated with desiccation resistance and negatively correlated with cuticular water loss but show lack of correlation with body size. We observed geographical variation in the amount of cuticular lipid mass per fly in Zaprionus ind... Fly journals http://www.medworm.com/rss/comments.php?id=1757545 Tue, 15 Jul 2008 04:00:00 +0100 1757545 http://www.medworm.com/index.php?rid=1757547&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18719404%26dopt%3DAbstract This study demonstrates that mutation of the drd gene CG33968 results in a complex phenotype affecting multiple physiological systems within the fly. PMID: 18719404 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=1757547 Thu, 03 Jul 2008 04:00:00 +0100 1757547 http://www.medworm.com/index.php?rid=1757559&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18504507%26dopt%3DAbstract Authors: Akbari OS, Schiller BJ, Goetz SE, Ho MC, Bae E, Drewell RA At the Drosophila bithorax complex many distinct classes of cis-regulatory modules work collectively during development to control gene expression. Abdominal-B (Abd-B) is one of three homeotic genes in the BX-C and is expressed in specific presumptive abdominal segments in the embryo. The transcription of Abd-B is tightly controlled by an array of cis-regulatory modules that direct its expression over extended genomic distances. These regulatory modules include promoters, insulators, silencers, enhancers, promoter targeting sequences and the recently identified promoter tethering element (PTE). To activate gene expression at the endogenous complex, enhancers located >50 kb away must bypass intervening insulators to ... Fly journals http://www.medworm.com/rss/comments.php?id=1757559 Sat, 01 Dec 2007 05:00:00 +0100 1757559 http://www.medworm.com/index.php?rid=1757558&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18618020%26dopt%3DAbstract Authors: Wiggins BL, Malik HS Increased size of eukaryotic genomes necessitated the use of multiple origins of DNA replication, and presumably selected for their efficient spacing to ensure rapid DNA replication. The sequence of these origins remains undetermined in metazoan genomes, leaving important questions about the selective constraints acting on replication origins unanswered. We have chosen to study the evolution of proteins that recognize and define these origins every cell cycle, as a surrogate to the direct analysis of replication origins. Among these DNA replication proteins is the essential Cdc6 protein, which acts to license origins for replication. We find that two different species pairs of Drosophila show evidence of positive selection in Cdc6 in their highly conserved... Fly journals http://www.medworm.com/rss/comments.php?id=1757558 Fri, 01 Jun 2007 04:00:00 +0100 1757558 http://www.medworm.com/index.php?rid=1757557&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18682693%26dopt%3DAbstract Authors: Fischer JA PMID: 18682693 [PubMed - as supplied by publisher] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=1757557 Tue, 13 Feb 2007 05:00:00 +0100 1757557 http://www.medworm.com/index.php?rid=1757556&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18690057%26dopt%3DAbstract We report here as a cautionary note that these vectors on their own can drive reporter gene expression in the larval and pupal salivary gland. PMID: 18690057 [PubMed - in process] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=1757556 Mon, 01 Jan 2007 05:00:00 +0100 1757556 http://www.medworm.com/index.php?rid=1757555&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18690058%26dopt%3DAbstract Authors: Riedl CA, Riedl M, Mackay TF, Sokolowski MB Drosophila melanogaster pupae are exposed to many biotic and abiotic dangers while immobilized during several days of metamorphosis. As a passive defense mechanism, appropriate pupation site selection represents an important mitigation of these threats. Pupation site selection is sensitive to genetic and environmental influences, but the specific mechanisms of the behavior are largely unknown. Using a set of 76 recombinant inbred strains we identify a single quantitative trait locus, at polytene position 56A01-C11, associated with pupation site variation. We furthermore present a detailed investigation into the wandering behaviors of two strains expressing different pupation position tendencies, and identify behavioral differences. L... Fly journals http://www.medworm.com/rss/comments.php?id=1757555 Mon, 01 Jan 2007 05:00:00 +0100 1757555 http://www.medworm.com/index.php?rid=1757554&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18690059%26dopt%3DAbstract Authors: Kelleher ES, Markow TA The process of speciation requires the development of isolating mechanisms that act as barriers to gene flow between incipient species. Such mechanisms can occur at three different levels: precopulatory or behavioral isolation, postcopulatory-prezygotic isolation occurring in the female reproductive tract, or postzygotic isolation resulting in hybrid sterility or inviability. Only by extensively studying all three types of barriers in young species pairs can we begin to understand the evolution of early reproductive incompatibilities, which may be important to the speciation process. Although precopulatory and postzygotic isolation have been well described it is only recently that the female reproductive tract has been intensely examined for possible mec... Fly journals http://www.medworm.com/rss/comments.php?id=1757554 Mon, 01 Jan 2007 05:00:00 +0100 1757554 http://www.medworm.com/index.php?rid=1757553&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18690060%26dopt%3DAbstract Authors: Haigh AJ, Lloyd VK Since the birth of the first cloned sheep in 1996, advances in nuclear transplantation have led to both the creation of genetically tailored stem cells and the generation of a number of cloned organisms. The list of cloned animals reared to adulthood currently includes the frog, sheep, mouse, cow, goat, pig, rabbit, cat, zebrafish, mule, horse, rat and dog. The addition of Drosophila to this elite bestiary of cloned animals has prompted the question - why clone flies? Organisms generated by nuclear transplantation suffer from a high rate of associated defects, and many of these defects appear to be related to aberrant genomic imprinting. Imprinted gene expression also appears to be compromised in Drosophila clones. Proper imprinted gene regulation relies on ... Fly journals http://www.medworm.com/rss/comments.php?id=1757553 Mon, 01 Jan 2007 05:00:00 +0100 1757553 http://www.medworm.com/index.php?rid=1757552&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18690061%26dopt%3DAbstract Authors: Gregory SL, Shandala T, O'Keefe L, Jones L, Murray MJ, Saint R To identify genes that modulate Rho signalling during cytokinesis we tested the effect of overexpressing a set of 2190 genes on an eye phenotype caused by defective Rho activation. The resulting 112 modifier loci fell into three main classes: cell cycle genes, signalling effectors and metabolic enzymes. We developed a further series of genetic tests to refine the interactors into those most likely to modify Rho signalling during cytokinesis. In addition to a number of genes previously implicated in the Rho pathway during cytokinesis, we identified four novel primary candidates: cdc14, Pitslre, PDK1 and thread/diap1. cdc14 orthologs have, however, been implicated in cytokinesis in other organisms, as have molecules ... Fly journals http://www.medworm.com/rss/comments.php?id=1757552 Mon, 01 Jan 2007 05:00:00 +0100 1757552 http://www.medworm.com/index.php?rid=1757551&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18690062%26dopt%3DAbstract Authors: Tountas NA, Fortini ME PMID: 18690062 [PubMed - in process] (Source: Fly) Fly journals http://www.medworm.com/rss/comments.php?id=1757551 Mon, 01 Jan 2007 05:00:00 +0100 1757551 http://www.medworm.com/index.php?rid=1757550&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18690063%26dopt%3DAbstract Authors: Aldridge AC, Benson LP, Siegenthaler MM, Whigham BT, Stowers RS, Hales KG Mitochondria undergo dramatic rearrangement during Drosophila spermatogenesis. In wild type testes, the many small mitochondria present in pre-meiotic spermatocytes later aggregate, fuse, and interwrap in post-meiotic haploid spermatids to form the spherical Nebenkern, whose two giant mitochondrial compartments later unfurl and elongate beside the growing flagellar axoneme. Drp1 encodes a dynamin-related protein whose homologs in many organisms mediate mitochondrial fission and whose Drosophila homolog is known to govern mitochondrial morphology in neurons. The milton gene encodes an adaptor protein that links mitochondria with kinesin and that is required for mitochondrial transport in Drosophila neuron... Fly journals http://www.medworm.com/rss/comments.php?id=1757550 Mon, 01 Jan 2007 05:00:00 +0100 1757550 http://www.medworm.com/index.php?rid=1757549&cid=s_37893_62_f&fid=37893&url=http%3A%2F%2Fwww.ncbi.nlm.nih.gov%2Fentrez%2Fquery.fcgi%3Ftmpl%3DNoSidebarfile%26db%3DPubMed%26cmd%3DRetrieve%26list_uids%3D18705022%26dopt%3DAbstract Authors: Perrimon N, Mathey-Prevot B Recently, the issue of off-target effects (OTEs) associated with long double stranded RNAs (dsRNAs) used in RNAi screens, such as those performed at the Drosophila RNAi Screening Center and other laboratories, has become a focus of great interest and some concern. Although OTEs have been recognized as an important source of false positives in mammalian studies (where short siRNAs are used as triggers), they were generally thought to be inconsequential in Drosophila RNAi experiments because of the use of long dsRNAs. Two recent papers have disputed this contention and show that significant off-target effects can take place with the use of some long dsRNAs in Drosophila cells. Together, these studies provide evidence that OTEs mediated by short homolo... Fly journals http://www.medworm.com/rss/comments.php?id=1757549 Mon, 01 Jan 2007 05:00:00 +0100 1757549