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Sample records for drosophila dishevelled segment-polarity

  1. Topology and Robustness in the Drosophila Segment Polarity Network

    PubMed Central

    2004-01-01

    A complex hierarchy of genetic interactions converts a single-celled Drosophila melanogaster egg into a multicellular embryo with 14 segments. Previously, von Dassow et al. reported that a mathematical model of the genetic interactions that defined the polarity of segments (the segment polarity network) was robust (von Dassow et al. 2000). As quantitative information about the system was unavailable, parameters were sampled randomly. A surprisingly large fraction of these parameter sets allowed the model to maintain and elaborate on the segment polarity pattern. This robustness is due to the positive feedback of gene products on their own expression, which induces individual cells in a model segment to adopt different stable expression states (bistability) corresponding to different cell types in the segment polarity pattern. A positive feedback loop will only yield multiple stable states when the parameters that describe it satisfy a particular inequality. By testing which random parameter sets satisfy these inequalities, I show that bistability is necessary to form the segment polarity pattern and serves as a strong predictor of which parameter sets will succeed in forming the pattern. Although the original model was robust to parameter variation, it could not reproduce the observed effects of cell division on the pattern of gene expression. I present a modified version that incorporates recent experimental evidence and does successfully mimic the consequences of cell division. The behavior of this modified model can also be understood in terms of bistability in positive feedback of gene expression. I discuss how this topological property of networks provides robust pattern formation and how large changes in parameters can change the specific pattern produced by a network. PMID:15208707

  2. Molecular cloning and characterization of human WINS1 and mouse Wins2, homologous to Drosophila segment polarity gene Lines (Lin).

    PubMed

    Katoh, Masaru

    2002-08-01

    WNT signaling molecules play key roles in carcinogenesis and embryogenesis. Drosophila segment polarity gene Lines (Lin) is essential for Wnt/Wingless-dependent patterning in dorsal epidermis and also for hindgut development. With Wnt signaling, Lin accumulates in the nucleus to modulate transcription of Wnt target genes through association with beta-catenin/Armadillo and TCF/Pangolin. Here, human WINS1 and mouse Wins2, encoding proteins with Drosophila Lin homologous domain, were isolated using bioinformatics and cDNA-PCR. Human WINS1 encoded 757-amino-acid protein, and mouse Wins2 encoded 498-amino-acid protein. Human WINS1 and mouse Wins2 showed 60.0% total-amino-acid identity. Lin homologous domain of WINS1 and Wins2 showed 29.4% and 27.2% amino-acid identity with that of Drosphila Lin, respectively. In the human chromosome 15q26 region, WINS1 gene was clustered with ASB7 gene encoding ankyrin repeat and SOCS box-containing protein 7. Human WINS1 mRNA of 2.8-kb in size was expressed in adult testis, prostate, spleen, thymus, skeletal muscle, fetal kidney and brain. This is the first report on molecular cloning and initial characterization of human WINS1 and mouse Wins2 PMID:12119551

  3. Isolation of a human gene with protein sequence similarity to human and murine int-1 and the Drosophila segment polarity mutant wingless.

    PubMed Central

    Wainwright, B J; Scambler, P J; Stanier, P; Watson, E K; Bell, G; Wicking, C; Estivill, X; Courtney, M; Boue, A; Pedersen, P S

    1988-01-01

    An expressed gene sequence which was identified by the isolation of a methylation free CpG island from human chromosome 7 has been cloned from a human lung cDNA library. The deduced protein sequence contains 360 amino acids and has several features of a secreted protein; it is cysteine rich with a signal peptide sequence and two potential asn-linked glycosylation sites. The protein sequence shows marked similarity with human and murine int-1 and their Drosophila homolog wingless (Dint-1). This human int-1 related protein, int-1 and Dint-1 have diverse patterns of expression, but the inferred structural similarities suggest that some of the functional characteristics of these proteins may be shared. Images PMID:2971536

  4. The segment polarity network is a robust developmental module

    NASA Astrophysics Data System (ADS)

    von Dassow, George; Meir, Eli; Munro, Edwin M.; Odell, Garrett M.

    2000-07-01

    All insects possess homologous segments, but segment specification differs radically among insect orders. In Drosophila, maternal morphogens control the patterned activation of gap genes, which encode transcriptional regulators that shape the patterned expression of pair-rule genes. This patterning cascade takes place before cellularization. Pair-rule gene products subsequently `imprint' segment polarity genes with reiterated patterns, thus defining the primordial segments. This mechanism must be greatly modified in insect groups in which many segments emerge only after cellularization. In beetles and parasitic wasps, for instance, pair-rule homologues are expressed in patterns consistent with roles during segmentation, but these patterns emerge within cellular fields. In contrast, although in locusts pair-rule homologues may not control segmentation, some segment polarity genes and their interactions are conserved. Perhaps segmentation is modular, with each module autonomously expressing a characteristic intrinsic behaviour in response to transient stimuli. If so, evolution could rearrange inputs to modules without changing their intrinsic behaviours. Here we suggest, using computer simulations, that the Drosophila segment polarity genes constitute such a module, and that this module is resistant to variations in the kinetic constants that govern its behaviour.

  5. Diego and Prickle regulate Frizzled planar cell polarity signalling by competing for Dishevelled binding.

    PubMed

    Jenny, Andreas; Reynolds-Kenneally, Jessica; Das, Gishnu; Burnett, Micheal; Mlodzik, Marek

    2005-07-01

    Epithelial planar cell polarity (PCP) is evident in the cellular organization of many tissues in vertebrates and invertebrates. In mammals, PCP signalling governs convergent extension during gastrulation and the organization of a wide variety of structures, including the orientation of body hair and sensory hair cells of the inner ear. In Drosophila melanogaster, PCP is manifest in adult tissues, including ommatidial arrangement in the compound eye and hair orientation in wing cells. PCP establishment requires the conserved Frizzled/Dishevelled PCP pathway. Mutations in PCP-pathway-associated genes cause aberrant orientation of body hair or inner-ear sensory cells in mice, or misorientation of ommatidia and wing hair in D. melanogaster. Here we provide mechanistic insight into Frizzled/Dishevelled signalling regulation. We show that the ankyrin-repeat protein Diego binds directly to Dishevelled and promotes Frizzled signalling. Dishevelled can also be bound by the Frizzled PCP antagonist Prickle. Strikingly, Diego and Prickle compete with one another for Dishevelled binding, thereby modulating Frizzled/Dishevelled activity and ensuring tight control over Frizzled PCP signalling. PMID:15937478

  6. Disinhibition of the HECT E3 ubiquitin ligase WWP2 by polymerized Dishevelled

    PubMed Central

    Mund, Thomas; Graeb, Michael; Mieszczanek, Juliusz; Gammons, Melissa; Pelham, Hugh R. B.; Bienz, Mariann

    2015-01-01

    Dishevelled is a pivot in Wnt signal transduction, controlling both β-catenin-dependent transcription to specify proliferative cell fates, and cell polarity and other non-nuclear events in post-mitotic cells. In response to Wnt signals, or when present at high levels, Dishevelled forms signalosomes by dynamic polymerization. Its levels are controlled by ubiquitylation, mediated by various ubiquitin ligases, including NEDD4 family members that bind to a conserved PPxY motif in Dishevelled (mammalian Dvl1–3). Here, we show that Dvl2 binds to the ubiquitin ligase WWP2 and unlocks its ligase activity from autoinhibition. This disinhibition of WWP2 depends on several features of Dvl2 including its PPxY motif and to a lesser extent its DEP domain, but crucially on the ability of Dvl2 to polymerize, indicating that WWP2 is activated in Wnt signalosomes. We show that Notch intracellular domains are substrates for Dvl-activated WWP2 and their transcriptional activity is consequently reduced, providing a molecular mechanism for cross-talk between Wnt and Notch signalling. These regulatory interactions are conserved in Drosophila whose WWP2 orthologue, Suppressor-of-deltex, downregulates Notch signalling upon activation by Dishevelled in developing wing tissue. Attentuation of Notch signalling by Dishevelled signalosomes could be important during the transition of cells from the proliferative to the post-mitotic state. PMID:26701932

  7. PDZ domain from Dishevelled -- a specificity study.

    PubMed

    Śmietana, Katarzyna; Mateja, Agnieszka; Krężel, Artur; Otlewski, Jacek

    2011-01-01

    Intracellular signaling cascades induced by Wnt proteins play a key role in developmental processes and are implicated in cancerogenesis. It is still unclear how the cell determines which of the three possible Wnt response mechanisms should be activated, but the decision process is most likely dependent on Dishevelled proteins. Dishevelled family members interact with many diverse targets, however, molecular mechanisms underlying these binding events have not been comprehensively described so far. Here, we investigated the specificity of the PDZ domain from human Dishevelled-2 using C-terminal phage display, which led us to identification of a leucine-rich binding motif strongly resembling the consensus sequence of a nuclear export signal. PDZ interactions with several peptide and protein motifs (including the nuclear export signal sequence from Dishevelled-2 protein) were investigated in detail using fluorescence spectroscopy, mutational analysis and immunoenzymatic assays. The experiments showed that the PDZ domain can bind the nuclear export signal sequence of the Dishevelled-2 protein. Since the intracellular localization of Dishevelled is governed by nuclear localization and nuclear export signal sequences, it is possible that the intramolecular interaction between PDZ domain and the export signal could modulate the balance between nuclear and cytoplasmic pool of the Dishevelled protein. Such a regulatory mechanism would be of utmost importance for the differential activation of Wnt signaling cascades, leading to selective promotion of the nucleus-dependent Wnt β-catenin pathway at the expense of non-canonical Wnt signaling. PMID:21666888

  8. PTEN regulates cilia through Dishevelled

    PubMed Central

    Shnitsar, Iryna; Bashkurov, Mikhail; Masson, Glenn R.; Ogunjimi, Abiodun A.; Mosessian, Sherly; Cabeza, Eduardo Aguiar; Hirsch, Calley L.; Trcka, Daniel; Gish, Gerald; Jiao, Jing; Wu, Hong; Winklbauer, Rudolf; Williams, Roger L.; Pelletier, Laurence; Wrana, Jeffrey L.; Barrios-Rodiles, Miriam

    2015-01-01

    Cilia are hair-like cellular protrusions important in many aspects of eukaryotic biology. For instance, motile cilia enable fluid movement over epithelial surfaces, while primary (sensory) cilia play roles in cellular signalling. The molecular events underlying cilia dynamics, and particularly their disassembly, are not well understood. Phosphatase and tensin homologue (PTEN) is an extensively studied tumour suppressor, thought to primarily act by antagonizing PI3-kinase signalling. Here we demonstrate that PTEN plays an important role in multicilia formation and cilia disassembly by controlling the phosphorylation of Dishevelled (DVL), another ciliogenesis regulator. DVL is a central component of WNT signalling that plays a role during convergent extension movements, which we show here are also regulated by PTEN. Our studies identify a novel protein substrate for PTEN that couples PTEN to regulation of cilia dynamics and WNT signalling, thus advancing our understanding of potential underlying molecular etiologies of PTEN-related pathologies. PMID:26399523

  9. The Adenomatous polyposis coli tumour suppressor is essential for Axin complex assembly and function and opposes Axin's interaction with Dishevelled.

    PubMed

    Mendoza-Topaz, Carolina; Mieszczanek, Juliusz; Bienz, Mariann

    2011-11-01

    Most cases of colorectal cancer are linked to mutational inactivation of the Adenomatous polyposis coli (APC) tumour suppressor. APC downregulates Wnt signalling by enabling Axin to promote the degradation of the Wnt signalling effector β-catenin (Armadillo in flies). This depends on Axin's DIX domain whose polymerization allows it to form dynamic protein assemblies ('degradasomes'). Axin is inactivated upon Wnt signalling, by heteropolymerization with the DIX domain of Dishevelled, which recruits it into membrane-associated 'signalosomes'. How APC promotes Axin's function is unclear, especially as it has been reported that APC's function can be bypassed by overexpression of Axin. Examining apc null mutant Drosophila tissues, we discovered that APC is required for Axin degradasome assembly, itself essential for Armadillo downregulation. Degradasome assembly is also attenuated in APC mutant cancer cells. Notably, Axin becomes prone to Dishevelled-dependent plasma membrane recruitment in the absence of APC, indicating a crucial role of APC in opposing the interaction of Axin with Dishevelled. Indeed, co-expression experiments reveal that APC displaces Dishevelled from Axin assemblies, promoting degradasome over signalosome formation in the absence of Wnts. APC thus empowers Axin to function in two ways-by enabling its DIX-dependent self-assembly, and by opposing its DIX-dependent copolymerization with Dishevelled and consequent inactivation. PMID:22645652

  10. Establishment of segment polarity in the ectoderm of the leech Helobdella

    NASA Technical Reports Server (NTRS)

    Seaver, E. C.; Shankland, M.

    2001-01-01

    The segmented ectoderm and mesoderm of the leech arise via a stereotyped cell lineage from embryonic stem cells called teloblasts. Each teloblast gives rise to a column of primary blast cell daughters, and the blast cells generate descendant clones that serve as the segmental repeats of their particular teloblast lineage. We have examined the mechanism by which the leech primary blast cell clones acquire segment polarity - i.e. a fixed sequence of positional values ordered along the anteroposterior axis of the segmental repeat. In the O and P teloblast lineages, the earliest divisions of the primary blast cell segregate anterior and posterior cell fates along the anteroposterior axis. Using a laser microbeam, we ablated single cells from both o and p blast cell clones at stages when the clone was two to four cells in length. The developmental fate of the remaining cells was characterized with rhodamine-dextran lineage tracer. Twelve different progeny cells were ablated, and in every case the ablation eliminated the normal descendants of the ablated cell while having little or no detectable effect on the developmental fate of the remaining cells. This included experiments in which we specifically ablated those blast cell progeny that are known to express the engrailed gene, or their lineal precursors. These findings confirm and extend a previous study by showing that the establishment of segment polarity in the leech ectoderm is largely independent of cell interactions conveyed along the anteroposterior axis. Both intercellular signaling and engrailed expression play an important role in the segment polarity specification of the Drosophila embryo, and our findings suggest that there may be little or no conservation of this developmental mechanism between those two organisms.

  11. The distribution of Dishevelled in convergently extending mesoderm☆

    PubMed Central

    Panousopoulou, Eleni; Tyson, Richard A.; Bretschneider, Till; Green, Jeremy B.A.

    2013-01-01

    Convergent extension (CE) is a conserved morphogenetic movement that drives axial lengthening of the primary body axis and depends on the planar cell polarity (PCP) pathway. In Drosophila epithelia, a polarised subcellular accumulation of PCP core components, such as Dishevelled (Dvl) protein, is associated with PCP function. Dvl has long been thought to accumulate in the mediolateral protrusions in Xenopus chordamesoderm cells undergoing CE. Here we present a quantitative analysis of Dvl intracellular localisation in Xenopus chordamesoderm cells. We find that, surprisingly, accumulations previously observed at mediolateral protrusions of chordamesodermal cells are not protrusion-specific but reflect yolk-free cytoplasm and are quantitatively matched by the distribution of the cytoplasm-filling lineage marker dextran. However, separating cell cortex-associated from bulk Dvl signal reveals a statistical enrichment of Dvl in notochord–somite boundary-(NSB)-directed protrusions, which is dependent upon NSB proximity. Dvl puncta were also observed, but only upon elevated overexpression. These puncta showed no statistically significant spatial bias, in contrast to the strongly posteriorly-enriched GFP-Dvl puncta previously reported in zebrafish. We propose that Dvl distribution is more subtle and dynamic than previously appreciated and that in vertebrate mesoderm it reflects processes other than protrusion as such. PMID:23876427

  12. The distribution of Dishevelled in convergently extending mesoderm.

    PubMed

    Panousopoulou, Eleni; Tyson, Richard A; Bretschneider, Till; Green, Jeremy B A

    2013-10-15

    Convergent extension (CE) is a conserved morphogenetic movement that drives axial lengthening of the primary body axis and depends on the planar cell polarity (PCP) pathway. In Drosophila epithelia, a polarised subcellular accumulation of PCP core components, such as Dishevelled (Dvl) protein, is associated with PCP function. Dvl has long been thought to accumulate in the mediolateral protrusions in Xenopus chordamesoderm cells undergoing CE. Here we present a quantitative analysis of Dvl intracellular localisation in Xenopus chordamesoderm cells. We find that, surprisingly, accumulations previously observed at mediolateral protrusions of chordamesodermal cells are not protrusion-specific but reflect yolk-free cytoplasm and are quantitatively matched by the distribution of the cytoplasm-filling lineage marker dextran. However, separating cell cortex-associated from bulk Dvl signal reveals a statistical enrichment of Dvl in notochord-somite boundary-(NSB)-directed protrusions, which is dependent upon NSB proximity. Dvl puncta were also observed, but only upon elevated overexpression. These puncta showed no statistically significant spatial bias, in contrast to the strongly posteriorly-enriched GFP-Dvl puncta previously reported in zebrafish. We propose that Dvl distribution is more subtle and dynamic than previously appreciated and that in vertebrate mesoderm it reflects processes other than protrusion as such. PMID:23876427

  13. Genetic analysis of disheveled 2 and disheveled 3 in human neural tube defects.

    PubMed

    De Marco, Patrizia; Merello, Elisa; Consales, Alessandro; Piatelli, Gianluca; Cama, Armando; Kibar, Zoha; Capra, Valeria

    2013-03-01

    Neural tube defects are severe malformations affecting 1/1,000 live births. The planar cell polarity pathway controls the neural tube closure and has been implicated in the pathogenesis of neural tube defects both in animal models and human cohorts. In mouse disruption of Dvl2 alone (Dvl2 (-/-)) or Dvl2 and Dvl3 (Dvl2 (-/-); Dvl3 (+/-), Dvl2 (+/-); Dvl3 (-/-)) results in incomplete neurulation, suggesting a role for Disheveled in neural tube closure. Disheveled is a multifunctional protein that is involved in both the canonical Wnt signaling and the noncanonical planar cell polarity pathway. In this study, we analyzed the role of the human orthologs DVL2 and DVL3 in a cohort of 473 patients with neural tube defects. Rare variants were genotyped in 639 ethnically matched controls. We identified seven rare missense mutations that were absent in all controls analyzed. Two of these mutations, p.Tyr667Cys and p.Ala53Val, identified in DVL2 were predicted to be detrimental in silico. Significantly, a 1-bp insertion (c.1801_1802insG) in exon 15 of DVL2 predicted to lead to the truncation of the protein was identified in a patient with a complex form of caudal agenesis. In summary, we demonstrate a possible role for rare variants in DVL2 gene as risk factors for neural tube defects. PMID:22892949

  14. Requirements for Hedgehog, a Segmental Polarity Gene, in Patterning Larval and Adult Cuticle of Drosophila

    PubMed Central

    Mohler, J.

    1988-01-01

    Mutations of the hedgehog gene are generally embryonic lethal, resulting in a lawn of denticles on the ventral surface. In strong alleles, no segmentation is obvious and the anteroposterior polarity of ventral denticles is lost. Temperature shift analysis of a temperature-sensitive allele indicates an embryonic activity period for hedgehog between 2.5 and 6 hr of embryonic development (at 25°) and a larval/pupal period from 4 to 7 days of development (at 25°). Mosaic analysis of hedgehog mutations in the adult cuticle indicates a series of defined defects associated with the failure of appropriate hedgehog expression. In particular, defects in the distal portions of the legs and antenna occur in association with homozygous hedgehog clones in the posterior compartment of those structures. Because the defects are associated with homozygous clones, but are not co-extensive, a type of ``domineering'' nonautonomy is proposed for the activity of the hedgehog gene. PMID:3147217

  15. Formin-mediated actin polymerization cooperates with Mushroom body defect (Mud)–Dynein during Frizzled–Dishevelled spindle orientation

    PubMed Central

    Johnston, Christopher A.; Manning, Laurina; Lu, Michelle S.; Golub, Ognjen; Doe, Chris Q.; Prehoda, Kenneth E.

    2013-01-01

    Summary To position the mitotic spindle, cytoskeletal components must be coordinated to generate cortical forces on astral microtubules. Although the dynein motor is common to many spindle orientation systems, ‘accessory pathways’ are often also required. In this work, we identified an accessory spindle orientation pathway in Drosophila that functions with Dynein during planar cell polarity, downstream of the Frizzled (Fz) effector Dishevelled (Dsh). Dsh contains a PDZ ligand and a Dynein-recruiting DEP domain that are both required for spindle orientation. The Dsh PDZ ligand recruits Canoe/Afadin and ultimately leads to Rho GTPase signaling mediated through RhoGEF2. The formin Diaphanous (Dia) functions as the Rho effector in this pathway, inducing F-actin enrichment at sites of cortical Dsh. Chimeric protein experiments show that the Dia–actin accessory pathway can be replaced by an independent kinesin (Khc73) accessory pathway for Dsh-mediated spindle orientation. Our results define two ‘modular’ spindle orientation pathways and show an essential role for actin regulation in Dsh-mediated spindle orientation. PMID:23868974

  16. Expression of dishevelled gene in Hirschsprung’s disease

    PubMed Central

    Chen, Dong; Mi, Jie; Wu, Mei; Wang, Weilin; Gao, Hong

    2013-01-01

    Hirschsprung’s disease (HSCR) is a congenital disorder of the enteric nervous system and is characterized by an absence of enteric ganglion cells in terminal regions of the gut during development. Dishevelled (DVL) protein is a cytoplasmic protein which plays pivotal roles in the embryonic development. In this study, we explore the cause of HSCR by studying the expression of DVL-1 and DVL-3 genes and their proteins in the aganglionic segment and the ganglionic segment of colon in HSCR patients. Materials and Methods: Specimen of aganglionic segment and ganglionic segment of colon in 50 cases of HSCR patients. Expression levels of mRNA and proteins of DVL-1 and DVL-3 were confirmed by quantitative real-time PCR (qRT-PCR), western blot and immunohistochemistry staining between the aganglionic segment and the ganglionic segment of colon in HSCR patients. Results: The mRNA expression of DVL-1 and DVL-3 were 2.06 fold and 3.12 fold in the aganglionic segment colon tissues compared to the ganglionic segment, respectively. Similarly, the proteins expression of DVL-1 and DVL-3 were higher (39.71 ± 4.53 vs and 53.90 ± 6.79 vs) in the aganglionic segment colon tissues than in the ganglionic segment (15.01 ± 2.66 and 20.13 ± 3.63) by western blot. Besides, immunohistochemical staining showed that DVL-1 and DVL-3 have a significant increase in mucous and submucous layers from aganglionic colon segments compared with ganglionic segments. Conclusion: The study showed an association of DVL-1 and DVL-3 with HSCR, it may play an important role in the pathogenesis of HSCR. PMID:24040443

  17. The Dishevelled Protein Family: Still Rather a Mystery After Over 20 Years of Molecular Studies

    PubMed Central

    Mlodzik, Marek

    2016-01-01

    Dishevelled (Dsh) is a key component of Wnt-signaling pathways and possibly also has other functional requirements. Dsh appears to be a key factor to interpret Wnt signals coming via the Wnt-receptor family, the Frizzled proteins, from the plasma membrane and route them into the correct intracellular pathways. However, how Dsh is regulated to relay signal flow to specific and distinct cellular responses upon interaction with the same Wnt-receptor family remains very poorly understood. PMID:26969973

  18. The Drosophila neurogenin Tap functionally interacts with the Wnt-PCP pathway to regulate neuronal extension and guidance.

    PubMed

    Yuan, Liqun; Hu, Shu; Okray, Zeynep; Ren, Xi; De Geest, Natalie; Claeys, Annelies; Yan, Jiekun; Bellefroid, Eric; Hassan, Bassem A; Quan, Xiao-Jiang

    2016-08-01

    The neurogenin (Ngn) transcription factors control early neurogenesis and neurite outgrowth in mammalian cortex. In contrast to their proneural activity, their function in neurite growth is poorly understood. Drosophila has a single predicted Ngn homolog, Tap, of unknown function. Here we show that Tap is not a proneural protein in Drosophila but is required for proper axonal growth and guidance of neurons of the mushroom body, a neuropile required for associative learning and memory. Genetic and expression analyses suggest that Tap inhibits excessive axonal growth by fine regulation of the levels of the Wnt signaling adaptor protein Dishevelled. PMID:27385016

  19. The Drosophila neurogenin Tap functionally interacts with the Wnt-PCP pathway to regulate neuronal extension and guidance

    PubMed Central

    Yuan, Liqun; Hu, Shu; Okray, Zeynep; Ren, Xi; De Geest, Natalie; Claeys, Annelies; Yan, Jiekun; Bellefroid, Eric; Quan, Xiao-Jiang

    2016-01-01

    The neurogenin (Ngn) transcription factors control early neurogenesis and neurite outgrowth in mammalian cortex. In contrast to their proneural activity, their function in neurite growth is poorly understood. Drosophila has a single predicted Ngn homolog, Tap, of unknown function. Here we show that Tap is not a proneural protein in Drosophila but is required for proper axonal growth and guidance of neurons of the mushroom body, a neuropile required for associative learning and memory. Genetic and expression analyses suggest that Tap inhibits excessive axonal growth by fine regulation of the levels of the Wnt signaling adaptor protein Dishevelled. PMID:27385016

  20. Dishevelled attenuates the repelling activity of Wnt signaling during neurite outgrowth in Caenorhabditis elegans.

    PubMed

    Zheng, Chaogu; Diaz-Cuadros, Margarete; Chalfie, Martin

    2015-10-27

    Wnt proteins regulate axonal outgrowth along the anterior-posterior axis, but the intracellular mechanisms that modulate the strength of Wnt signaling in axon guidance are largely unknown. Using the Caenorhabditis elegans mechanosensory PLM neurons, we found that posteriorly enriched LIN-44/Wnt acts as a repellent to promote anteriorly directed neurite outgrowth through the LIN-17/Frizzled receptor, instead of controlling neuronal polarity as previously thought. Dishevelled (Dsh) proteins DSH-1 and MIG-5 redundantly mediate the repulsive activity of the Wnt signals to induce anterior outgrowth, whereas DSH-1 also provides feedback inhibition to attenuate the signaling to allow posterior outgrowth against the Wnt gradient. This inhibitory function of DSH-1, which requires its dishevelled, Egl-10, and pleckstrin (DEP) domain, acts by promoting LIN-17 phosphorylation and is antagonized by planar cell polarity signaling components Van Gogh (VANG-1) and Prickle (PRKL-1). Our results suggest that Dsh proteins both respond to Wnt signals to shape neuronal projections and moderate its activity to fine-tune neuronal morphology. PMID:26460008

  1. Dishevelled is a NEK2 kinase substrate controlling dynamics of centrosomal linker proteins.

    PubMed

    Cervenka, Igor; Valnohova, Jana; Bernatik, Ondrej; Harnos, Jakub; Radsetoulal, Matej; Sedova, Katerina; Hanakova, Katerina; Potesil, David; Sedlackova, Miroslava; Salasova, Alena; Steinhart, Zachary; Angers, Stephane; Schulte, Gunnar; Hampl, Ales; Zdrahal, Zbynek; Bryja, Vitezslav

    2016-08-16

    Dishevelled (DVL) is a key scaffolding protein and a branching point in Wnt signaling pathways. Here, we present conclusive evidence that DVL regulates the centrosomal cycle. We demonstrate that DVL dishevelled and axin (DIX) domain, but not DIX domain-mediated multimerization, is essential for DVL's centrosomal localization. DVL accumulates during the cell cycle and associates with NIMA-related kinase 2 (NEK2), which is able to phosphorylate DVL at a multitude of residues, as detected by a set of novel phospho-specific antibodies. This creates interfaces for efficient binding to CDK5 regulatory subunit-associated protein 2 (CDK5RAP2) and centrosomal Nek2-associated protein 1 (C-NAP1), two proteins of the centrosomal linker. Displacement of DVL from the centrosome and its release into the cytoplasm on NEK2 phosphorylation is coupled to the removal of linker proteins, an event necessary for centrosomal separation and proper formation of the mitotic spindle. Lack of DVL prevents NEK2-controlled dissolution of loose centrosomal linker and subsequent centrosomal separation. Increased DVL levels, in contrast, sequester centrosomal NEK2 and mimic monopolar spindle defects induced by a dominant negative version of this kinase. Our study thus uncovers molecular crosstalk between centrosome and Wnt signaling. PMID:27486244

  2. Dishevelled attenuates the repelling activity of Wnt signaling during neurite outgrowth in Caenorhabditis elegans

    PubMed Central

    Zheng, Chaogu; Diaz-Cuadros, Margarete; Chalfie, Martin

    2015-01-01

    Wnt proteins regulate axonal outgrowth along the anterior–posterior axis, but the intracellular mechanisms that modulate the strength of Wnt signaling in axon guidance are largely unknown. Using the Caenorhabditis elegans mechanosensory PLM neurons, we found that posteriorly enriched LIN-44/Wnt acts as a repellent to promote anteriorly directed neurite outgrowth through the LIN-17/Frizzled receptor, instead of controlling neuronal polarity as previously thought. Dishevelled (Dsh) proteins DSH-1 and MIG-5 redundantly mediate the repulsive activity of the Wnt signals to induce anterior outgrowth, whereas DSH-1 also provides feedback inhibition to attenuate the signaling to allow posterior outgrowth against the Wnt gradient. This inhibitory function of DSH-1, which requires its dishevelled, Egl-10, and pleckstrin (DEP) domain, acts by promoting LIN-17 phosphorylation and is antagonized by planar cell polarity signaling components Van Gogh (VANG-1) and Prickle (PRKL-1). Our results suggest that Dsh proteins both respond to Wnt signals to shape neuronal projections and moderate its activity to fine-tune neuronal morphology. PMID:26460008

  3. Overexpression of Dishevelled-2 contributes to proliferation and migration of human esophageal squamous cell carcinoma.

    PubMed

    Zhou, Guoren; Ye, Jinjun; Sun, Lei; Zhang, Zhi; Feng, Jifeng

    2016-06-01

    Dishevelled-2 (Dvl2) was associated with tumor cell proliferation and migration. We aimed to examine the mechanism of Dvl2 in esophageal squamous cell carcinoma (ESCC). Dvl2 was overexpressed in human ESCC tissues and cell lines ECA109 and TE1 cells. CCK-8 and colony formation assay was performed to evaluate the proliferation in ECA109 cells transfected with Dvl2-shRNA. Wound-healing assay and transwell assay were used to examine the activities of migration and invasion in Dvl2-silenced ESCC cells. Knockdown of Dvl2 significantly reduced ECA109 cell proliferation and migration. Moreover, we demonstrated that the proliferation and migration ability of Dvl2 might through the activation of Wnt pathway by targeting the Cyclin D1 and MMP-9. We came to the conclusion that the proliferation and migration effects of Dvl2 might contribute to malignant development of human ESCC. PMID:27083564

  4. Expression of segment polarity genes in brachiopods supports a non-segmental ancestral role of engrailed for bilaterians

    PubMed Central

    Vellutini, Bruno C.; Hejnol, Andreas

    2016-01-01

    The diverse and complex developmental mechanisms of segmentation have been more thoroughly studied in arthropods, vertebrates and annelids—distantly related animals considered to be segmented. Far less is known about the role of “segmentation genes” in organisms that lack a segmented body. Here we investigate the expression of the arthropod segment polarity genes engrailed, wnt1 and hedgehog in the development of brachiopods—marine invertebrates without a subdivided trunk but closely related to the segmented annelids. We found that a stripe of engrailed expression demarcates the ectodermal boundary that delimits the anterior region of Terebratalia transversa and Novocrania anomala embryos. In T. transversa, this engrailed domain is abutted by a stripe of wnt1 expression in a pattern similar to the parasegment boundaries of insects—except for the expression of hedgehog, which is restricted to endodermal tissues of the brachiopod embryos. We found that pax6 and pax2/5/8, putative regulators of engrailed, also demarcate the anterior boundary in the two species, indicating these genes might be involved in the anterior patterning of brachiopod larvae. In a comparative phylogenetic context, these findings suggest that bilaterians might share an ancestral, non-segmental domain of engrailed expression during early embryogenesis. PMID:27561213

  5. Expression of segment polarity genes in brachiopods supports a non-segmental ancestral role of engrailed for bilaterians.

    PubMed

    Vellutini, Bruno C; Hejnol, Andreas

    2016-01-01

    The diverse and complex developmental mechanisms of segmentation have been more thoroughly studied in arthropods, vertebrates and annelids-distantly related animals considered to be segmented. Far less is known about the role of "segmentation genes" in organisms that lack a segmented body. Here we investigate the expression of the arthropod segment polarity genes engrailed, wnt1 and hedgehog in the development of brachiopods-marine invertebrates without a subdivided trunk but closely related to the segmented annelids. We found that a stripe of engrailed expression demarcates the ectodermal boundary that delimits the anterior region of Terebratalia transversa and Novocrania anomala embryos. In T. transversa, this engrailed domain is abutted by a stripe of wnt1 expression in a pattern similar to the parasegment boundaries of insects-except for the expression of hedgehog, which is restricted to endodermal tissues of the brachiopod embryos. We found that pax6 and pax2/5/8, putative regulators of engrailed, also demarcate the anterior boundary in the two species, indicating these genes might be involved in the anterior patterning of brachiopod larvae. In a comparative phylogenetic context, these findings suggest that bilaterians might share an ancestral, non-segmental domain of engrailed expression during early embryogenesis. PMID:27561213

  6. CYLD regulates spindle orientation by stabilizing astral microtubules and promoting dishevelled-NuMA-dynein/dynactin complex formation.

    PubMed

    Yang, Yunfan; Liu, Min; Li, Dengwen; Ran, Jie; Gao, Jinmin; Suo, Shaojun; Sun, Shao-Cong; Zhou, Jun

    2014-02-11

    Oriented cell division is critical for cell fate specification, tissue organization, and tissue homeostasis, and relies on proper orientation of the mitotic spindle. The molecular mechanisms underlying the regulation of spindle orientation remain largely unknown. Herein, we identify a critical role for cylindromatosis (CYLD), a deubiquitinase and regulator of microtubule dynamics, in the control of spindle orientation. CYLD is highly expressed in mitosis and promotes spindle orientation by stabilizing astral microtubules and deubiquitinating the cortical polarity protein dishevelled. The deubiquitination of dishevelled enhances its interaction with nuclear mitotic apparatus, stimulating the cortical localization of nuclear mitotic apparatus and the dynein/dynactin motor complex, a requirement for generating pulling forces on astral microtubules. These findings uncover CYLD as an important player in the orientation of the mitotic spindle and cell division and have important implications in health and disease. PMID:24469800

  7. Modulation of Dishevelled and Vangl2 by all-trans-retinoic acid in the developing mouse central nervous system and its relationship to teratogenesis.

    PubMed

    Zhang, Yanping; Liu, Kai; Gao, Yingmao; Li, Shaoling

    2007-09-01

    The response to exposure to all-trans-retinoic acid (RA) during embryogenesis varies from physiologic to severe teratogenic effects and is dependent upon the dose and the stage of development in all species. Vangl2 and Dishevelled genes play key roles in establishing planar cell polarity and regulating convergent extension movements during the neurula period. The effects of RA-mediated teratogenesis might be due to its misregulation of Vangl2 and Dishevelled genes. The aim of this study is to monitor the modulation of Vangl2 and Dishevelled in Kunming mouse embryos following maternal treatment with a single oral dose of 30 mg/(kg body weight) of RA during the neurula period. Exposure of 7.75 d embryos to RA induced characteristic morphological changes. The most obvious external effect was the failure of neural tube closure in the midbrain and forebrain regions in 10 d embryos, resulting in exencephaly in later embryos. RA treatment also led to a pronounced decrease of Vangl2 mRNA at 4 and 18 h and a pronounced increase at 66 h after maternal treatment, as detected by reverse transcription-polymerase chain reaction. Western blot analysis showed a marked decrease of Vangl2 protein at 18 and 42 h and a marked increase at 66 and 90 h after maternal treatment. Dishevelled1/2/3 mRNA was significantly down-regulated at 4 and 18 h and up-regulated at 42 h in the fetus after RA treatment, except for an up-regulation of Dishevelled3 at 66 h. The Dishevelled2 mRNA and its protein matched each other. These results hinted that Vangl2 and Dishevelled genes might take part in RA teratogenesis of mouse embryos. PMID:17805463

  8. Generating patterns from fields of cells. Examples from Drosophila segmentation.

    PubMed

    Sanson, B

    2001-12-01

    In Drosophila, a cascade of maternal, gap, pair-rule and segment polarity genes subdivides the antero/posterior axis of the embryo into repeating segmental stripes. This review summarizes what happens next, i.e. how an intrasegmental pattern is generated and controls the differentiation of specific cell types in the epidermis. Within each segment, cells secreting the signalling molecules Wingless (the homologue of vertebrate Wnt-1) and Hedgehog are found in narrow stripes on both sides of the parasegmental boundary. The Wingless and Hedgehog organizing activities help to establish two more stripes per segment that localize ligands for the Epidermal Growth Factor and the Notch signalling pathways, respectively. These four signals then act at short range and in concert to control epidermal differentiation at the single cell level across the segment. This example from Drosophila provides a paradigm for how organizers generate precise patterns, and ultimately different cell types, in a naïve field of cells. PMID:11743020

  9. Loss of Dishevelleds disrupts planar polarity in ependymal motile cilia and results in hydrocephalus

    PubMed Central

    Ohata, Shinya; Nakatani, Jin; Herranz-Pérez, Vicente; Cheng, JrGang; Belinson, Haim; Inubushi, Toshiro; Snider, William D.; García-Verdugo, Jose Manuel; Wynshaw-Boris, Anthony; Álvarez-Buylla, Arturo

    2014-01-01

    SUMMARY Defects in ependymal (E) cells, which line the ventricle and generate cerebrospinal fluid flow through ciliary beating, can cause hydrocephalus. Dishevelled genes (Dvls) are essential for Wnt signaling and Dvl2 has been shown to localize to the rootlet of motile cilia. Using the hGFAP-Cre;Dvl1−/−;2flox/flox;3+/− mouse, we show that compound genetic ablation of Dvls causes hydrocephalus. In hGFAP-Cre;Dvl1−/−;2flox/flox;3+/− mutants, E cells differentiated normally, but the intracellular and intercellular rotational alignments of ependymal motile cilia were disrupted. As a consequence, the fluid flow generated by the hGFAP-Cre;Dvl1−/−;2flox/flox;3+/− E cells was significantly slower than that observed in control mice. Dvls were also required for the proper positioning of motile cilia on the apical surface. Tamoxifen-induced conditional removal of Dvls in adult mice also resulted in defects in intracellular rotational alignment and positioning of ependymal motile cilia. These results suggest that Dvls are continuously required for E cell planar polarity and may prevent hydrocephalus. PMID:25043421

  10. Loss of Dishevelleds disrupts planar polarity in ependymal motile cilia and results in hydrocephalus.

    PubMed

    Ohata, Shinya; Nakatani, Jin; Herranz-Pérez, Vicente; Cheng, JrGang; Belinson, Haim; Inubushi, Toshiro; Snider, William D; García-Verdugo, Jose Manuel; Wynshaw-Boris, Anthony; Alvarez-Buylla, Arturo

    2014-08-01

    Defects in ependymal (E) cells, which line the ventricle and generate cerebrospinal fluid flow through ciliary beating, can cause hydrocephalus. Dishevelled genes (Dvls) are essential for Wnt signaling, and Dvl2 has been shown to localize to the rootlet of motile cilia. Using the hGFAP-Cre;Dvl1(-/-);2(flox/flox);3(+/-) mouse, we show that compound genetic ablation of Dvls causes hydrocephalus. In hGFAP-Cre;Dvl1(-/-);2(flox/flox);3(+/-) mutants, E cells differentiated normally, but the intracellular and intercellular rotational alignments of ependymal motile cilia were disrupted. As a consequence, the fluid flow generated by the hGFAP-Cre;Dvl1(-/-);2(flox/flox);3(+/-) E cells was significantly slower than that observed in control mice. Dvls were also required for the proper positioning of motile cilia on the apical surface. Tamoxifen-induced conditional removal of Dvls in adult mice also resulted in defects in intracellular rotational alignment and positioning of ependymal motile cilia. These results suggest that Dvls are continuously required for E cell planar polarity and may prevent hydrocephalus. PMID:25043421

  11. Dishevelled is essential for neural connectivity and planar cell polarity in planarians.

    PubMed

    Almuedo-Castillo, Maria; Saló, Emili; Adell, Teresa

    2011-02-15

    The Wingless/Integrated (Wnt) signaling pathway controls multiple events during development and homeostasis. It comprises multiple branches, mainly classified according to their dependence on β-catenin activation. The Wnt/β-catenin branch is essential for the establishment of the embryonic anteroposterior (AP) body axis throughout the phylogenetic tree. It is also required for AP axis establishment during planarian regeneration. Wnt/β-catenin-independent signaling encompasses several different pathways, of which the most extensively studied is the planar cell polarity (PCP) pathway, which is responsible for planar polarization of cell structures within an epithelial sheet. Dishevelled (Dvl) is the hub of Wnt signaling because it regulates and channels the Wnt signal into every branch. Here, we analyze the role of Schmidtea mediterranea Dvl homologs (Smed-dvl-1 and Smed-dvl-2) using gene silencing. We demonstrate that in addition to a role in AP axis specification, planarian Dvls are involved in at least two different β-catenin-independent processes. First, they are essential for neural connectivity through Smed-wnt5 signaling. Second, Smed-dvl-2, together with the S. mediterranea homologs of Van-Gogh (Vang) and Diversin (Div), is required for apical positioning of the basal bodies of epithelial cells. These data represent evidence not only of the function of the PCP network in lophotrocozoans but of the involvement of the PCP core elements Vang and Div in apical positioning of the cilia. PMID:21282632

  12. Ubiquitination of the Dishevelled DIX domain blocks its head-to-tail polymerization

    PubMed Central

    Madrzak, Julia; Fiedler, Marc; Johnson, Christopher M.; Ewan, Richard; Knebel, Axel; Bienz, Mariann; Chin, Jason W.

    2015-01-01

    Dishevelled relays Wnt signals from the plasma membrane to different cytoplasmic effectors. Its signalling activity depends on its DIX domain, which undergoes head-to-tail polymerization to assemble signalosomes. The DIX domain is ubiquitinated in vivo at multiple lysines, which can be antagonized by various deubiquitinases (DUBs) including the CYLD tumour suppressor that attenuates Wnt signalling. Here, we generate milligram quantities of pure human Dvl2 DIX domain mono-ubiquitinated at two lysines (K54 and K58) by genetically encoded orthogonal protection with activated ligation (GOPAL), to investigate their effect on DIX polymerization. We show that the ubiquitination of DIX at K54 blocks its polymerization in solution, whereas DIX58-Ub remains oligomerization-competent. DUB profiling identified 28 DUBs that cleave DIX-ubiquitin conjugates, half of which prefer, or are specific for, DIX54-Ub, including Cezanne and CYLD. These DUBs thus have the potential to promote Dvl polymerization and signalosome formation, rather than antagonize it as previously thought for CYLD. PMID:25907794

  13. The Dishevelled-binding protein CXXC5 negatively regulates cutaneous wound healing

    PubMed Central

    Lee, Soung-Hoon; Kim, Mi-Yeon; Kim, Hyun-Yi; Lee, Young-Mi; Kim, Heesu; Nam, Kyoung Ae; Roh, Mi Ryung; Min, Do Sik; Chung, Kee Yang

    2015-01-01

    Wnt/β-catenin signaling plays important roles in cutaneous wound healing and dermal fibrosis. However, its regulatory mechanism has not been fully elucidated, and a commercially available wound-healing agent targeting this pathway is desirable but currently unavailable. We found that CXXC-type zinc finger protein 5 (CXXC5) serves as a negative feedback regulator of the Wnt/β-catenin pathway by interacting with the Dishevelled (Dvl) protein. In humans, CXXC5 protein levels were reduced in epidermal keratinocytes and dermal fibroblasts of acute wounds. A differential regulation of β-catenin, α-smooth muscle actin (α-SMA), and collagen I by overexpression and silencing of CXXC5 in vitro indicated a critical role for this factor in myofibroblast differentiation and collagen production. In addition, CXXC5−/− mice exhibited accelerated cutaneous wound healing, as well as enhanced keratin 14 and collagen synthesis. Protein transduction domain (PTD)–Dvl-binding motif (DBM), a competitor peptide blocking CXXC5-Dvl interactions, disrupted this negative feedback loop and activated β-catenin and collagen production in vitro. Co-treatment of skin wounds with PTD-DBM and valproic acid (VPA), a glycogen synthase kinase 3β (GSK3β) inhibitor which activates the Wnt/β-catenin pathway, synergistically accelerated cutaneous wound healing in mice. Together, these data suggest that CXXC5 would represent a potential target for future therapies aimed at improving wound healing. PMID:26056233

  14. The Dishevelled-binding protein CXXC5 negatively regulates cutaneous wound healing.

    PubMed

    Lee, Soung-Hoon; Kim, Mi-Yeon; Kim, Hyun-Yi; Lee, Young-Mi; Kim, Heesu; Nam, Kyoung Ae; Roh, Mi Ryung; Min, Do Sik; Chung, Kee Yang; Choi, Kang-Yell

    2015-06-29

    Wnt/β-catenin signaling plays important roles in cutaneous wound healing and dermal fibrosis. However, its regulatory mechanism has not been fully elucidated, and a commercially available wound-healing agent targeting this pathway is desirable but currently unavailable. We found that CXXC-type zinc finger protein 5 (CXXC5) serves as a negative feedback regulator of the Wnt/β-catenin pathway by interacting with the Dishevelled (Dvl) protein. In humans, CXXC5 protein levels were reduced in epidermal keratinocytes and dermal fibroblasts of acute wounds. A differential regulation of β-catenin, α-smooth muscle actin (α-SMA), and collagen I by overexpression and silencing of CXXC5 in vitro indicated a critical role for this factor in myofibroblast differentiation and collagen production. In addition, CXXC5(-/-) mice exhibited accelerated cutaneous wound healing, as well as enhanced keratin 14 and collagen synthesis. Protein transduction domain (PTD)-Dvl-binding motif (DBM), a competitor peptide blocking CXXC5-Dvl interactions, disrupted this negative feedback loop and activated β-catenin and collagen production in vitro. Co-treatment of skin wounds with PTD-DBM and valproic acid (VPA), a glycogen synthase kinase 3β (GSK3β) inhibitor which activates the Wnt/β-catenin pathway, synergistically accelerated cutaneous wound healing in mice. Together, these data suggest that CXXC5 would represent a potential target for future therapies aimed at improving wound healing. PMID:26056233

  15. Distinct functionality of dishevelled isoforms on Ca2+/calmodulin-dependent protein kinase 2 (CamKII) in Xenopus gastrulation

    PubMed Central

    Gentzel, Marc; Schille, Carolin; Rauschenberger, Verena; Schambony, Alexandra

    2015-01-01

    Wnt ligands trigger the activation of a variety of β-catenin–dependent and β-catenin–independent intracellular signaling cascades. Despite the variations in intracellular signaling, Wnt pathways share the effector proteins frizzled, dishevelled, and β-arrestin. It is unclear how the specific activation of individual branches and the integration of multiple signals are achieved. We hypothesized that the composition of dishevelled–β-arrestin protein complexes contributes to signal specificity and identified CamKII as an interaction partner of the dishevelled–β-arrestin protein complex by quantitative functional proteomics. Specifically, we found that CamKII isoforms interact differentially with the three vertebrate dishevelled proteins. Dvl1 is required for the activation of CamKII and PKC in the Wnt/Ca2+ pathway. However, CamKII interacts with Dvl2 but not with Dvl1, and Dvl2 is necessary to mediate CamKII function downstream of Dvl1 in convergent extension movements in Xenopus gastrulation. Our findings indicate that the different Dvl proteins and the composition of dishevelled–β-arrestin protein complexes contribute to the specific activation of individual branches of Wnt signaling. PMID:25568338

  16. Controversies Surrounding Segments and Parasegments in Onychophora: Insights from the Expression Patterns of Four “Segment Polarity Genes” in the Peripatopsid Euperipatoides rowelli

    PubMed Central

    Franke, Franziska Anni; Mayer, Georg

    2014-01-01

    Arthropods typically show two types of segmentation: the embryonic parasegments and the adult segments that lie out of register with each other. Such a dual nature of body segmentation has not been described from Onychophora, one of the closest arthropod relatives. Hence, it is unclear whether onychophorans have segments, parasegments, or both, and which of these features was present in the last common ancestor of Onychophora and Arthropoda. To address this issue, we analysed the expression patterns of the “segment polarity genes” engrailed, cubitus interruptus, wingless and hedgehog in embryos of the onychophoran Euperipatoides rowelli. Our data revealed that these genes are expressed in repeated sets with a specific anterior-to-posterior order along the body in embryos of E. rowelli. In contrast to arthropods, the expression occurs after the segmental boundaries have formed. Moreover, the initial segmental furrow retains its position within the engrailed domain throughout development, whereas no new furrow is formed posterior to this domain. This suggests that no re-segmentation of the embryo occurs in E. rowelli. Irrespective of whether or not there is a morphological or genetic manifestation of parasegments in Onychophora, our data clearly show that parasegments, even if present, cannot be regarded as the initial metameric units of the onychophoran embryo, because the expression of key genes that define the parasegmental boundaries in arthropods occurs after the segmental boundaries have formed. This is in contrast to arthropods, in which parasegments rather than segments are the initial metameric units of the embryo. Our data further revealed that the expression patterns of “segment polarity genes” correspond to organogenesis rather than segment formation. This is in line with the concept of segmentation as a result of concerted evolution of individual periodic structures rather than with the interpretation of ‘segments’ as holistic units. PMID

  17. Controversies surrounding segments and parasegments in onychophora: insights from the expression patterns of four "segment polarity genes" in the peripatopsid Euperipatoides rowelli.

    PubMed

    Franke, Franziska Anni; Mayer, Georg

    2014-01-01

    Arthropods typically show two types of segmentation: the embryonic parasegments and the adult segments that lie out of register with each other. Such a dual nature of body segmentation has not been described from Onychophora, one of the closest arthropod relatives. Hence, it is unclear whether onychophorans have segments, parasegments, or both, and which of these features was present in the last common ancestor of Onychophora and Arthropoda. To address this issue, we analysed the expression patterns of the "segment polarity genes" engrailed, cubitus interruptus, wingless and hedgehog in embryos of the onychophoran Euperipatoides rowelli. Our data revealed that these genes are expressed in repeated sets with a specific anterior-to-posterior order along the body in embryos of E. rowelli. In contrast to arthropods, the expression occurs after the segmental boundaries have formed. Moreover, the initial segmental furrow retains its position within the engrailed domain throughout development, whereas no new furrow is formed posterior to this domain. This suggests that no re-segmentation of the embryo occurs in E. rowelli. Irrespective of whether or not there is a morphological or genetic manifestation of parasegments in Onychophora, our data clearly show that parasegments, even if present, cannot be regarded as the initial metameric units of the onychophoran embryo, because the expression of key genes that define the parasegmental boundaries in arthropods occurs after the segmental boundaries have formed. This is in contrast to arthropods, in which parasegments rather than segments are the initial metameric units of the embryo. Our data further revealed that the expression patterns of "segment polarity genes" correspond to organogenesis rather than segment formation. This is in line with the concept of segmentation as a result of concerted evolution of individual periodic structures rather than with the interpretation of 'segments' as holistic units. PMID:25470738

  18. Csrp1 regulates dynamic cell movements of the mesendoderm and cardiac mesoderm through interactions with Dishevelled and Diversin

    PubMed Central

    Miyasaka, Kota Y.; Kida, Yasuyuki S.; Sato, Takayuki; Minami, Mari; Ogura, Toshihiko

    2007-01-01

    Zebrafish Csrp1 is a member of the cysteine- and glycine-rich protein (CSRP) family and is expressed in the mesendoderm and its derivatives. Csrp1 interacts with Dishevelled 2 (Dvl2) and Diversin (Div), which control cell morphology and other dynamic cell behaviors via the noncanonical Wnt and JNK pathways. When csrp1 message is knocked down, abnormal convergent extension cell movement is induced, resulting in severe deformities in midline structures. In addition, cardiac bifida is induced as a consequence of defects in cardiac mesoderm cell migration. Our data highlight Csrp1 as a key molecule of the noncanonical Wnt pathway, which orchestrates cell behaviors during dynamic morphogenetic movements of tissues and organs. PMID:17592114

  19. Quantitative analysis of gene function in the Drosophila embryo.

    PubMed Central

    Tracey, W D; Ning, X; Klingler, M; Kramer, S G; Gergen, J P

    2000-01-01

    The specific functions of gene products frequently depend on the developmental context in which they are expressed. Thus, studies on gene function will benefit from systems that allow for manipulation of gene expression within model systems where the developmental context is well defined. Here we describe a system that allows for genetically controlled overexpression of any gene of interest under normal physiological conditions in the early Drosophila embryo. This regulated expression is achieved through the use of Drosophila lines that express a maternal mRNA for the yeast transcription factor GAL4. Embryos derived from females that express GAL4 maternally activate GAL4-dependent UAS transgenes at uniform levels throughout the embryo during the blastoderm stage of embryogenesis. The expression levels can be quantitatively manipulated through the use of lines that have different levels of maternal GAL4 activity. Specific phenotypes are produced by expression of a number of different developmental regulators with this system, including genes that normally do not function during Drosophila embryogenesis. Analysis of the response to overexpression of runt provides evidence that this pair-rule segmentation gene has a direct role in repressing transcription of the segment-polarity gene engrailed. The maternal GAL4 system will have applications both for the measurement of gene activity in reverse genetic experiments as well as for the identification of genetic factors that have quantitative effects on gene function in vivo. PMID:10628987

  20. Frizzled-4 C-terminus Distal to KTXXXW Motif is Essential for Normal Dishevelled Recruitment and Norrin-stimulated Activation of Lef/Tcf-dependent Transcriptional Activation.

    PubMed

    Bertalovitz, Alexander C; Pau, Milly S; Gao, Shujuan; Malbon, Craig C; Wang, Hsien-Yu

    2016-01-01

    The carboxy (C)-termini of G protein coupled receptors (GPCR) dictate essential functions. The KTXXXW motif C-terminus of Frizzleds (FZD) has been implicated in recruitment of Dishevelled (DVL). Through study of FZD4 and its associated ligand Norrin, we report that a minimum of three residues distal to the KTXXXW motif in the C-terminal tail of Frizzled-4 are essential for DVL recruitment and robust Lef/Tcf-dependent transcriptional activation in response to Norrin. PMID:27096005

  1. Frizzled-4 C-terminus Distal to KTXXXW Motif is Essential for Normal Dishevelled Recruitment and Norrin-stimulated Activation of Lef/Tcf-dependent Transcriptional Activation

    PubMed Central

    Pau, Milly S.; Gao, Shujuan; Malbon, Craig C.; Wang, Hsien-yu

    2016-01-01

    The carboxy (C)-termini of G protein coupled receptors (GPCR) dictate essential functions. The KTXXXW motif C-terminus of Frizzleds (FZD) has been implicated in recruitment of Dishevelled (DVL). Through study of FZD4 and its associated ligand Norrin, we report that a minimum of three residues distal to the KTXXXW motif in the C-terminal tail of Frizzled-4 are essential for DVL recruitment and robust Lef/Tcf-dependent transcriptional activation in response to Norrin. PMID:27096005

  2. Drosophila spermiogenesis

    PubMed Central

    Fabian, Lacramioara; Brill, Julie A.

    2012-01-01

    Drosophila melanogaster spermatids undergo dramatic morphological changes as they differentiate from small round cells approximately 12 μm in diameter into highly polarized, 1.8 mm long, motile sperm capable of participating in fertilization. During spermiogenesis, syncytial cysts of 64 haploid spermatids undergo synchronous differentiation. Numerous changes occur at a subcellular level, including remodeling of existing organelles (mitochondria, nuclei), formation of new organelles (flagellar axonemes, acrosomes), polarization of elongating cysts and plasma membrane addition. At the end of spermatid morphogenesis, organelles, mitochondrial DNA and cytoplasmic components not needed in mature sperm are stripped away in a caspase-dependent process called individualization that results in formation of individual sperm. Here, we review the stages of Drosophila spermiogenesis and examine our current understanding of the cellular and molecular mechanisms involved in shaping male germ cell-specific organelles and forming mature, fertile sperm. PMID:23087837

  3. Drosophila myogenesis.

    PubMed

    Bothe, Ingo; Baylies, Mary K

    2016-09-12

    The skeletal muscle system is the largest organ in motile animals, constituting between 35 and 55% of the human body mass, and up to 75% of the body mass in flying organisms like Drosophila. The flight muscles alone in flying insects comprise up to 65% of total body mass. Not only is the musculature the largest organ system, it is also exquisitely complex, with single muscles existing in different shapes and sizes. These different morphologies allow for such different functions as the high-frequency beating of a wing in a hummingbird, the dilation of the pupil in a human eye, or the maintenance of posture in a giraffe's neck. PMID:27623256

  4. Structural Analysis of the Interaction between Dishevelled2 and Clathrin AP-2 Adaptor, A Critical Step in Noncanonical Wnt Signaling

    SciTech Connect

    Yu, Anan; Xing, Yi; Harrison, Stephen C.; Kirchhausen, Tomas

    2010-10-14

    Wnt association with its receptor, Frizzled (Fz), and recruitment by the latter of an adaptor, Dishevelled (Dvl), initiates signaling through at least two distinct pathways (canonical and noncanonical). Endocytosis and compartmentalization help determine the signaling outcome. Our previous work has shown that Dvl2 links at least one Frizzled family member (Fz4) to clathrin-mediated endocytosis by interacting with the {mu}2 subunit of the AP-2 clathrin adaptor, through both a classical endocytic tyrosine motif and a so-called DEP domain. We report here the crystal structure of a chimeric protein that mimics the Dvl2-{mu}2 complex. The DEP domain binds at one end of the elongated, C-terminal domain of {mu}2. This domain:domain interface shows that parts of the {mu}2 surface distinct from the tyrosine-motif site can help recruit specific receptors or adaptors into a clathrin coated pit. Mutation of residues at the DEP-{mu}2 contact or in the tyrosine motif reduce affinity of Dvl2 for {mu}2 and block efficient internalization of Fz4 in response to ligation by Wnt5a. The crystal structure has thus allowed us to identify the specific interaction that leads to Frizzled uptake and to downstream, noncanonical signaling events.

  5. Small molecule inhibitors of the Dishevelled-CXXC5 interaction are new drug candidates for bone anabolic osteoporosis therapy.

    PubMed

    Kim, Hyun-Yi; Choi, Sehee; Yoon, Ji-Hye; Lim, Hwan Jung; Lee, Hyuk; Choi, Jiwon; Ro, Eun Ji; Heo, Jung-Nyoung; Lee, Weontae; No, Kyoung Tai; Choi, Kang-Yell

    2016-01-01

    Bone anabolic agents promoting bone formation and rebuilding damaged bones would ideally overcome the limitations of anti-resorptive therapy, the current standard prescription for osteoporosis. However, the currently prescribed parathyroid hormone (PTH)-based anabolic drugs present limitations and adverse effects including osteosarcoma during long-term use. Also, the antibody-based anabolic drugs that are currently being developed present the potential limits in clinical application typical of macromolecule drugs. We previously identified that CXXC5 is a negative feedback regulator of the Wnt/β-catenin pathway via its interaction with Dishevelled (Dvl) and suggested the Dvl-CXXC5 interaction as a potential target for anabolic therapy of osteoporosis. Here, we screened small-molecule inhibitors of the Dvl-CXXC5 interaction via a newly established in vitro assay system. The screened compounds were found to activate the Wnt/β-catenin pathway and enhance osteoblast differentiation in primary osteoblasts. The bone anabolic effects of the compounds were shown using ex vivo-cultured calvaria. Nuclear magnetic resonance (NMR) titration analysis confirmed interaction between Dvl PDZ domain and KY-02061, a representative of the screened compounds. Oral administration of KY-02327, one of 55 newly synthesized KY-02061 analogs, successfully rescued bone loss in the ovariectomized (OVX) mouse model. In conclusion, small-molecule inhibitors of the Dvl-CXXC5 interaction that block negative feedback regulation of Wnt/β-catenin signaling are potential candidates for the development of bone anabolic anti-osteoporosis drugs. PMID:26941261

  6. Identification of small-molecule compounds targeting the dishevelled PDZ domain by virtual screening and binding studies.

    PubMed

    Choi, Jiwon; Ma, SongLing; Kim, Hyun-Yi; Yun, Ji-Hye; Heo, Jung-Nyoung; Lee, Weontae; Choi, Kang-Yell; No, Kyoung Tai

    2016-08-01

    The Dishevelled (Dvl) protein, which conveys signals from receptors to the downstream effectors, is a critical constituent of the Wnt/β-catenin signaling pathway. Because the PDZ domain of Dvl protein functions through associations with a wide range of protein partners, Dvl protein involved in the Wnt signaling pathway has been considered to be therapeutic targets in cancers. In this study, we performed structure-based pharmacophore model of the Dvl PDZ domain to discover novel small-molecule binders and identified eight compounds with micromolar affinity. The most potent compound identified, BMD4702, efficiently bound to the Dvl PDZ domain with 11.2μM affinity and had a 0.186μM KD value according to surface plasmon resonance and fluorescence spectroscopy, respectively. Combining both structural-kinetic relationship analyses and docking studies, we fourmulated that the ligand-binding site is composed of three H-bonds and three hydrophobic features. Thus, our approach led to the identification of potent binders of the Dvl PDZ domain and the findings provide novel insights into structure-based approaches to design high-affinity binders for the Dvl PDZ domain. PMID:27112452

  7. Kif26b controls endothelial cell polarity through the Dishevelled/Daam1-dependent planar cell polarity–signaling pathway

    PubMed Central

    Guillabert-Gourgues, Aude; Jaspard-Vinassa, Beatrice; Bats, Marie-Lise; Sewduth, Raj N.; Franzl, Nathalie; Peghaire, Claire; Jeanningros, Sylvie; Moreau, Catherine; Roux, Etienne; Larrieu-Lahargue, Frederic; Dufourcq, Pascale; Couffinhal, Thierry; Duplàa, Cecile

    2016-01-01

    Angiogenesis involves the coordinated growth and migration of endothelial cells (ECs) toward a proangiogenic signal. The Wnt planar cell polarity (PCP) pathway, through the recruitment of Dishevelled (Dvl) and Dvl-associated activator of morphogenesis (Daam1), has been proposed to regulate cell actin cytoskeleton and microtubule (MT) reorganization for oriented cell migration. Here we report that Kif26b—a kinesin—and Daam1 cooperatively regulate initiation of EC sprouting and directional migration via MT reorganization. First, we find that Kif26b is recruited within the Dvl3/Daam1 complex. Using a three-dimensional in vitro angiogenesis assay, we show that Kif26b and Daam1 depletion impairs tip cell polarization and destabilizes extended vascular processes. Kif26b depletion specifically alters EC directional migration and mislocalized MT organizing center (MTOC)/Golgi and myosin IIB cell rear enrichment. Therefore the cell fails to establish a proper front–rear polarity. Of interest, Kif26b ectopic expression rescues the siDaam1 polarization defect phenotype. Finally, we show that Kif26b functions in MT stabilization, which is indispensable for asymmetrical cell structure reorganization. These data demonstrate that Kif26b, together with Dvl3/Daam1, initiates cell polarity through the control of PCP signaling pathway–dependent activation. PMID:26792835

  8. Kif26b controls endothelial cell polarity through the Dishevelled/Daam1-dependent planar cell polarity-signaling pathway.

    PubMed

    Guillabert-Gourgues, Aude; Jaspard-Vinassa, Beatrice; Bats, Marie-Lise; Sewduth, Raj N; Franzl, Nathalie; Peghaire, Claire; Jeanningros, Sylvie; Moreau, Catherine; Roux, Etienne; Larrieu-Lahargue, Frederic; Dufourcq, Pascale; Couffinhal, Thierry; Duplàa, Cecile

    2016-03-15

    Angiogenesis involves the coordinated growth and migration of endothelial cells (ECs) toward a proangiogenic signal. The Wnt planar cell polarity (PCP) pathway, through the recruitment of Dishevelled (Dvl) and Dvl-associated activator of morphogenesis (Daam1), has been proposed to regulate cell actin cytoskeleton and microtubule (MT) reorganization for oriented cell migration. Here we report that Kif26b-a kinesin-and Daam1 cooperatively regulate initiation of EC sprouting and directional migration via MT reorganization. First, we find that Kif26b is recruited within the Dvl3/Daam1 complex. Using a three-dimensional in vitro angiogenesis assay, we show that Kif26b and Daam1 depletion impairs tip cell polarization and destabilizes extended vascular processes. Kif26b depletion specifically alters EC directional migration and mislocalized MT organizing center (MTOC)/Golgi and myosin IIB cell rear enrichment. Therefore the cell fails to establish a proper front-rear polarity. Of interest, Kif26b ectopic expression rescues the siDaam1 polarization defect phenotype. Finally, we show that Kif26b functions in MT stabilization, which is indispensable for asymmetrical cell structure reorganization. These data demonstrate that Kif26b, together with Dvl3/Daam1, initiates cell polarity through the control of PCP signaling pathway-dependent activation. PMID:26792835

  9. Deciphering the onychophoran 'segmentation gene cascade': Gene expression reveals limited involvement of pair rule gene orthologs in segmentation, but a highly conserved segment polarity gene network.

    PubMed

    Janssen, Ralf; Budd, Graham E

    2013-10-01

    The hallmark of the arthropods is their segmented body, although origin of segmentation, however, is unresolved. In order to shed light on the origin of segmentation we investigated orthologs of pair rule genes (PRGs) and segment polarity genes (SPGs) in a member of the closest related sister-group to the arthropods, the onychophorans. Our gene expression data analysis suggests that most of the onychophoran PRGs do not play a role in segmentation. One possible exception is the even-skipped (eve) gene that is expressed in the posterior end of the onychophoran where new segments are likely patterned, and is also expressed in segmentation-gene typical transverse stripes in at least a number of newly formed segments. Other onychophoran PRGs such as runt (run), hairy/Hes (h/Hes) and odd-skipped (odd) do not appear to have a function in segmentation at all. Onychophoran PRGs that act low in the segmentation gene cascade in insects, however, are potentially involved in segment-patterning. Most obvious is that from the expression of the pairberry (pby) gene ortholog that is expressed in a typical SPG-pattern. Since this result suggested possible conservation of the SPG-network we further investigated SPGs (and associated factors) such as Notum in the onychophoran. We find that the expression patterns of SPGs in arthropods and the onychophoran are highly conserved, suggesting a conserved SPG-network in these two clades, and indeed also in an annelid. This may suggest that the common ancestor of lophotrochozoans and ecdysozoans was already segmented utilising the same SPG-network, or that the SPG-network was recruited independently in annelids and onychophorans/arthropods. PMID:23880430

  10. Functional Analysis of Dishevelled-3 Phosphorylation Identifies Distinct Mechanisms Driven by Casein Kinase 1ϵ and Frizzled5*

    PubMed Central

    Bernatík, Ondřej; Šedová, Kateřina; Schille, Carolin; Ganji, Ranjani Sri; Červenka, Igor; Trantírek, Lukáš; Schambony, Alexandra; Zdráhal, Zbyněk; Bryja, Vítězslav

    2014-01-01

    Dishevelled-3 (Dvl3), a key component of the Wnt signaling pathways, acts downstream of Frizzled (Fzd) receptors and gets heavily phosphorylated in response to pathway activation by Wnt ligands. Casein kinase 1ϵ (CK1ϵ) was identified as the major kinase responsible for Wnt-induced Dvl3 phosphorylation. Currently it is not clear which Dvl residues are phosphorylated and what is the consequence of individual phosphorylation events. In the present study we employed mass spectrometry to analyze in a comprehensive way the phosphorylation of human Dvl3 induced by CK1ϵ. Our analysis revealed >50 phosphorylation sites on Dvl3; only a minority of these sites was found dynamically induced after co-expression of CK1ϵ, and surprisingly, phosphorylation of one cluster of modified residues was down-regulated. Dynamically phosphorylated sites were analyzed functionally. Mutations within PDZ domain (S280A and S311A) reduced the ability of Dvl3 to activate TCF/LEF (T-cell factor/lymphoid enhancer factor)-driven transcription and induce secondary axis in Xenopus embryos. In contrast, mutations of clustered Ser/Thr in the Dvl3 C terminus prevented ability of CK1ϵ to induce electrophoretic mobility shift of Dvl3 and its even subcellular localization. Surprisingly, mobility shift and subcellular localization changes induced by Fzd5, a Wnt receptor, were in all these mutants indistinguishable from wild type Dvl3. In summary, our data on the molecular level (i) support previous the assumption that CK1ϵ acts via phosphorylation of distinct residues as the activator as well as the shut-off signal of Wnt/β-catenin signaling and (ii) suggest that CK1ϵ acts on Dvl via different mechanism than Fzd5. PMID:24993822

  11. The Drosophila visual system

    PubMed Central

    Zhu, Yan

    2013-01-01

    A compact genome and a tiny brain make Drosophila the prime model to understand the neural substrate of behavior. The neurogenetic efforts to reveal neural circuits underlying Drosophila vision started about half a century ago, and now the field is booming with sophisticated genetic tools, rich behavioral assays, and importantly, a greater number of scientists joining from different backgrounds. This review will briefly cover the structural anatomy of the Drosophila visual system, the animal’s visual behaviors, the genes involved in assembling these circuits, the new and powerful techniques, and the challenges ahead for ultimately identifying the general principles of biological computation in the brain.   A typical brain utilizes a great many compact neural circuits to collect and process information from the internal biological and external environmental worlds and generates motor commands for observable behaviors. The fruit fly Drosophila melanogaster, despite of its miniature body and tiny brain, can survive in almost any corner of the world.1 It can find food, court mate, fight rival conspecific, avoid predators, and amazingly fly without crashing into trees. Drosophila vision and its underlying neuronal machinery has been a key research model for at least half century for neurogeneticists.2 Given the efforts invested on the visual system, this animal model is likely to offer the first full understanding of how visual information is computed by a multi-cellular organism. Furthermore, research in Drosophila has revealed many genes that play crucial roles in the formation of functional brains across species. The architectural similarities between the visual systems of Drosophila and vertebrate at the molecular, cellular, and network levels suggest new principles discovered at the circuit level on the relationship between neurons and behavior in Drosophila shall also contribute greatly to our understanding of the general principles for how bigger brains work.3

  12. Drosophila Blastorderm Analysis Software

    SciTech Connect

    2006-10-25

    PointCloudMake analyzes 3D fluorescent images of whole Drosophila embryo and produces a table-style "PointCloud" file which contains the coordinates and volumes of all the nuclei, cells, their associated relative gene expression levels along with morphological features of the embryo. See: Luengo Hendrix et at 2006 3D Morphology and Gene Expression in the Drosophila Blastoderm at Cellular Resolution manuscript submitted LBNL # LBNL-60178 Knowles DW, Keranen SVE, Biggin M. Sudar S (2002) Mapping organism expression levels at cellular resolution in developing Drosophila. In: Conchello JA, Cogswell CJ, Wilson T, editors. Three-Dimensional and Multidimensional Microscopy: Image Acquisition and Processing IX. pp. 57-64

  13. Meiosis in male Drosophila

    PubMed Central

    McKee, Bruce D.; Yan, Rihui; Tsai, Jui-He

    2012-01-01

    Meiosis entails sorting and separating both homologous and sister chromatids. The mechanisms for connecting sister chromatids and homologs during meiosis are highly conserved and include specialized forms of the cohesin complex and a tightly regulated homolog synapsis/recombination pathway designed to yield regular crossovers between homologous chromatids. Drosophila male meiosis is of special interest because it dispenses with large segments of the standard meiotic script, particularly recombination, synapsis and the associated structures. Instead, Drosophila relies on a unique protein complex composed of at least two novel proteins, SNM and MNM, to provide stable connections between homologs during meiosis I. Sister chromatid cohesion in Drosophila is mediated by cohesins, ring-shaped complexes that entrap sister chromatids. However, unlike other eukaryotes Drosophila does not rely on the highly conserved Rec8 cohesin in meiosis, but instead utilizes two novel cohesion proteins, ORD and SOLO, which interact with the SMC1/3 cohesin components in providing meiotic cohesion. PMID:23087836

  14. In focus: spotted wing drosophila, Drosophila suzukii, across perspectives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An effective response to the invasion of spotted wing Drosophila (SWD), Drosophila suzukii, requires proper taxonomic identification at the initial phase, understanding its basic biology and phenology, developing management tools, transferring information and technology quickly to user groups, and e...

  15. Different Wnt signals act through the Frizzled and RYK receptors during Drosophila salivary gland migration.

    PubMed

    Harris, Katherine E; Beckendorf, Steven K

    2007-06-01

    Guided cell migration is necessary for the proper function and development of many tissues, one of which is the Drosophila embryonic salivary gland. Here we show that two distinct Wnt signaling pathways regulate salivary gland migration. Early in migration, the salivary gland responds to a WNT4-Frizzled signal for proper positioning within the embryo. Disruption of this signal, through mutations in Wnt4, frizzled or frizzled 2, results in misguided salivary glands that curve ventrally. Furthermore, disruption of downstream components of the canonical Wnt pathway, such as dishevelled or Tcf, also results in ventrally curved salivary glands. Analysis of a second Wnt signal, which acts through the atypical Wnt receptor Derailed, indicates a requirement for Wnt5 signaling late in salivary gland migration. WNT5 is expressed in the central nervous system and acts as a repulsive signal, needed to keep the migrating salivary gland on course. The receptor for WNT5, Derailed, is expressed in the actively migrating tip of the salivary glands. In embryos mutant for derailed or Wnt5, salivary gland migration is disrupted; the tip of the gland migrates abnormally toward the central nervous system. Our results suggest that both the Wnt4-frizzled pathway and a separate Wnt5-derailed pathway are needed for proper salivary gland migration. PMID:17507403

  16. Drosophila Blastorderm Analysis Software

    Energy Science and Technology Software Center (ESTSC)

    2006-10-25

    PointCloudMake analyzes 3D fluorescent images of whole Drosophila embryo and produces a table-style "PointCloud" file which contains the coordinates and volumes of all the nuclei, cells, their associated relative gene expression levels along with morphological features of the embryo. See: Luengo Hendrix et at 2006 3D Morphology and Gene Expression in the Drosophila Blastoderm at Cellular Resolution manuscript submitted LBNL # LBNL-60178 Knowles DW, Keranen SVE, Biggin M. Sudar S (2002) Mapping organism expression levelsmore » at cellular resolution in developing Drosophila. In: Conchello JA, Cogswell CJ, Wilson T, editors. Three-Dimensional and Multidimensional Microscopy: Image Acquisition and Processing IX. pp. 57-64« less

  17. Temporal pattern of the posterior expression of Wingless in Drosophila blastoderm

    PubMed Central

    Vorwald-Denholtz, Peggy P.; De Robertis, Edward M.

    2011-01-01

    In most animals, the Antero-Posterior (A-P) axis requires a gradient of Wnt signaling. Wnts are expressed posteriorly in many vertebrate and invertebrate embryos, forming a gradient of canonical Wnt/β-Catenin activity that is highest in the posterior and lowest in the anterior. One notable exception to this evolutionary conservation is in the Drosophila embryo, in which the A-P axis is established by early transcription factors of maternal origin. Despite this initial axial establishment, Drosophila still expresses Wingless (Wg), the main Drosophila Wnt homologue, in a strong posterior band early in embryogenesis. Since its discovery 30 years ago this posterior band of Wg has been largely ignored. In this study, we re-examined the onset of expression of the Wg posterior band in relation to the expression of Wg in other segments, and compared the timing of its expression to that of axial regulators such as gap and pair-rule genes. It was found that the posterior band of Wg is first detected in blastoderm at mid nuclear cycle 14, before the segment-polarity stripes of Wg are formed in other segments. The onset of the posterior band of Wg expression was preceded by that of the gap gene products Hunchback (hb) and Krüppel (Kr), and the pair-rule protein Even-skipped (Eve). Although the function of the posterior band of Wg was not analyzed in this study, we note that in temperature-sensitive Wg mutants, in which Wg is not properly secreted, the posterior band of Wg expression is diminished in strength, indicating a positive feedback loop required for Wg robust expression at the cellular blastoderm stage. We propose that this early posterior expression could play a role in the refinement of A-P patterning. PMID:21821151

  18. Heritable Endosymbionts of Drosophila

    PubMed Central

    Mateos, Mariana; Castrezana, Sergio J.; Nankivell, Becky J.; Estes, Anne M.; Markow, Therese A.; Moran, Nancy A.

    2006-01-01

    Although heritable microorganisms are increasingly recognized as widespread in insects, no systematic screens for such symbionts have been conducted in Drosophila species (the primary insect genetic models for studies of evolution, development, and innate immunity). Previous efforts screened relatively few Drosophila lineages, mainly for Wolbachia. We conducted an extensive survey of potentially heritable endosymbionts from any bacterial lineage via PCR screens of mature ovaries in 181 recently collected fly strains representing 35 species from 11 species groups. Due to our fly sampling methods, however, we are likely to have missed fly strains infected with sex ratio-distorting endosymbionts. Only Wolbachia and Spiroplasma, both widespread in insects, were confirmed as symbionts. These findings indicate that in contrast to some other insect groups, other heritable symbionts are uncommon in Drosophila species, possibly reflecting a robust innate immune response that eliminates many bacteria. A more extensive survey targeted these two symbiont types through diagnostic PCR in 1225 strains representing 225 species from 32 species groups. Of these, 19 species were infected by Wolbachia while only 3 species had Spiroplasma. Several new strains of Wolbachia and Spiroplasma were discovered, including ones divergent from any reported to date. The phylogenetic distribution of Wolbachia and Spiroplasma in Drosophila is discussed. PMID:16783009

  19. Differential Regulation of Disheveled in a Novel Vegetal Cortical Domain in Sea Urchin Eggs and Embryos: Implications for the Localized Activation of Canonical Wnt Signaling

    PubMed Central

    Peng, ChiehFu Jeff; Wikramanayake, Athula H.

    2013-01-01

    Pattern formation along the animal-vegetal (AV) axis in sea urchin embryos is initiated when canonical Wnt (cWnt) signaling is activated in vegetal blastomeres. The mechanisms that restrict cWnt signaling to vegetal blastomeres are not well understood, but there is increasing evidence that the egg’s vegetal cortex plays a critical role in this process by mediating localized “activation” of Disheveled (Dsh). To investigate how Dsh activity is regulated along the AV axis, sea urchin-specific Dsh antibodies were used to examine expression, subcellular localization, and post-translational modification of Dsh during development. Dsh is broadly expressed during early sea urchin development, but immunolocalization studies revealed that this protein is enriched in a punctate pattern in a novel vegetal cortical domain (VCD) in the egg. Vegetal blastomeres inherit this VCD during embryogenesis, and at the 60-cell stage Dsh puncta are seen in all cells that display nuclear β-catenin. Analysis of Dsh post-translational modification using two-dimensional Western blot analysis revealed that compared to Dsh pools in the bulk cytoplasm, this protein is differentially modified in the VCD and in the 16-cell stage micromeres that partially inherit this domain. Dsh localization to the VCD is not directly affected by disruption of microfilaments and microtubules, but unexpectedly, microfilament disruption led to degradation of all the Dsh pools in unfertilized eggs over a period of incubation suggesting that microfilament integrity is required for maintaining Dsh stability. These results demonstrate that a pool of differentially modified Dsh in the VCD is selectively inherited by the vegetal blastomeres that activate cWnt signaling in early embryos, and suggests that this domain functions as a scaffold for localized Dsh activation. Localized cWnt activation regulates AV axis patterning in many metazoan embryos. Hence, it is possible that the VCD is an evolutionarily conserved

  20. Aging Studies in Drosophila melanogaster

    PubMed Central

    Sun, Yaning; Yolitz, Jason; Wang, Cecilia; Spangler, Edward; Zhan, Ming; Zou, Sige

    2015-01-01

    Summary Drosophila is a genetically tractable system ideal for investigating the mechanisms of aging and developing interventions for promoting healthy aging. Here we describe methods commonly used in Drosophila aging research. These include basic approaches for preparation of diets and measurements of lifespan, food intake and reproductive output. We also describe some commonly used assays to measure changes in physiological and behavioral functions of Drosophila in aging, such as stress resistance and locomotor activity. PMID:23929099

  1. Drosophila by the dozen

    SciTech Connect

    Celniker, Susan E.; Hoskins, Roger A.

    2007-07-13

    This year's conference on Drosophila research illustratedwell the current focus of Drosophila genomics on the comprehensiveidentification of functional elements in the genome sequence, includingmRNA transcripts arising from multiple alternative start sites and splicesites, a multiplicity of noncoding transcripts and small RNAs,identification of binding sites for transcription factors, sequenceconservation in related species and sequence variation within species.Resources and technologies for genetics and functional genomics aresteadily being improved, including the building of collections oftransposon insertion mutants and hairpin constructs for RNA interference(RNAi). The conference also highlighted progress in the use of genomicinformation by many laboratories to study diverse aspects of biology andmodels of human disease. Here we will review a few highlights of especialinterest to readers of Genome Biology.

  2. The Drosophila Auditory System

    PubMed Central

    Boekhoff-Falk, Grace; Eberl, Daniel F.

    2013-01-01

    Development of a functional auditory system in Drosophila requires specification and differentiation of the chordotonal sensilla of Johnston’s organ (JO) in the antenna, correct axonal targeting to the antennal mechanosensory and motor center (AMMC) in the brain, and synaptic connections to neurons in the downstream circuit. Chordotonal development in JO is functionally complicated by structural, molecular and functional diversity that is not yet fully understood, and construction of the auditory neural circuitry is only beginning to unfold. Here we describe our current understanding of developmental and molecular mechanisms that generate the exquisite functions of the Drosophila auditory system, emphasizing recent progress and highlighting important new questions arising from research on this remarkable sensory system. PMID:24719289

  3. Van Gogh and Frizzled Act Redundantly in the Drosophila Sensory Organ Precursor Cell to Orient Its Asymmetric Division

    PubMed Central

    Schweisguth, François

    2009-01-01

    Drosophila sensory organ precursor cells (SOPs) divide asymmetrically along the anterior-posterior (a-p) body axis to generate two different daughter cells. Planar Cell Polarity (PCP) regulates the a-p orientation of the SOP division. The localization of the PCP proteins Van Gogh (Vang) and Frizzled (Fz) define anterior and posterior apical membrane domains prior to SOP division. Here, we investigate the relative contributions of Vang, Fz and Dishevelled (Dsh), a membrane-associated protein acting downstream of Fz, in orienting SOP polarity. Genetic and live imaging analyses suggest that Dsh restricts the localization of a centrosome-attracting activity to the anterior cortex and that Vang is a target of Dsh in this process. Using a clone border assay, we provide evidence that the Vang and fz genes act redundantly in SOPs to orient its polarity axis in response to extrinsic local PCP cues. Additionally, we find that the activity of Vang is dispensable for the non-autonomous polarizing activity of fz. These observations indicate that both Vang and Fz act as cues for downstream effectors orienting the planar polarity axis of dividing SOPs. PMID:19214234

  4. An unconventional nuclear localization motif is crucial for function of the Drosophila Wnt/wingless antagonist Naked cuticle.

    PubMed

    Waldrop, Sharon; Chan, Chih-Chiang; Cagatay, Tolga; Zhang, Shu; Rousset, Raphaël; Mack, Judy; Zeng, Wenlin; Fish, Matt; Zhang, Mei; Amanai, Manami; Wharton, Keith A

    2006-09-01

    Wnt/beta-catenin signals orchestrate cell fate and behavior throughout the animal kingdom. Aberrant Wnt signaling impacts nearly the entire spectrum of human disease, including birth defects, cancer, and osteoporosis. If Wnt signaling is to be effectively manipulated for therapeutic advantage, we first must understand how Wnt signals are normally controlled. Naked cuticle (Nkd) is a novel and evolutionarily conserved inducible antagonist of Wnt/beta-catenin signaling that is crucial for segmentation in the model genetic organism, the fruit fly Drosophila melanogaster. Nkd can bind and inhibit the Wnt signal transducer Dishevelled (Dsh), but the mechanism by which Nkd limits Wnt signaling in the fly embryo is not understood. Here we show that nkd mutants exhibit elevated levels of the beta-catenin homolog Armadillo but no alteration in Dsh abundance or distribution. In the fly embryo, Nkd and Dsh are predominantly cytoplasmic, although a recent report suggests that vertebrate Dsh requires nuclear localization for activity in gain-of-function assays. While Dsh-binding regions of Nkd contribute to its activity, we identify a conserved 30-amino-acid motif, separable from Dsh-binding regions, that is essential for Nkd function and nuclear localization. Replacement of the 30-aa motif with a conventional nuclear localization sequence rescued a small fraction of nkd mutant animals to adulthood. Our studies suggest that Nkd targets Dsh-dependent signal transduction steps in both cytoplasmic and nuclear compartments of cells receiving the Wnt signal. PMID:16849595

  5. Protease-activated receptor-1 (PAR1) acts via a novel Galpha13-dishevelled axis to stabilize beta-catenin levels.

    PubMed

    Turm, Hagit; Maoz, Myriam; Katz, Vered; Yin, Yong-Jun; Offermanns, Steffan; Bar-Shavit, Rachel

    2010-05-14

    We have previously shown a novel link between hPar-1 (human protease-activated receptor-1) and beta-catenin stabilization. Although it is well recognized that Wnt signaling leads to beta-catenin accumulation, the role of PAR1 in the process is unknown. We provide here evidence that PAR1 induces beta-catenin stabilization independent of Wnt, Fz (Frizzled), and the co-receptor LRP5/6 (low density lipoprotein-related protein 5/6) and identify selective mediators of the PAR1-beta-catenin axis. Immunohistological analyses of hPar1-transgenic (TG) mouse mammary tissues show the expression of both Galpha(12) and Galpha(13) compared with age-matched control counterparts. However, only Galpha(13) was found to be actively involved in PAR1-induced beta-catenin stabilization. Indeed, a dominant negative form of Galpha(13) inhibited both PAR1-induced Matrigel invasion and Lef/Tcf (lymphoid enhancer factor/T cell factor) transcription activity. PAR1-Galpha(13) association is followed by the recruitment of DVL (Dishevelled), an upstream Wnt signaling protein via the DIX domain. Small interfering RNA-Dvl silencing leads to a reduction in PAR1-induced Matrigel invasion, inhibition of Lef/Tcf transcription activity, and decreased beta-catenin accumulation. It is of note that PAR1 also promotes the binding of beta-arrestin-2 to DVL, suggesting a role for beta-arrestin-2 in PAR1-induced DVL phosphorylation dynamics. Although infection of small interfering RNA-LRP5/6 or the use of the Wnt antagonists, SFRP2 (soluble Frizzled-related protein 2) or SFRP5 potently reduced Wnt3A-mediated beta-catenin accumulation, no effect was observed on PAR1-induced beta-catenin stabilization. Collectively, our data show that PAR1 mediates beta-catenin stabilization independent of Wnt. We propose here a novel cascade of PAR1-induced Galpha(13)-DVL axis in cancer and beta-catenin stabilization. PMID:20223821

  6. Coexpression of IQ-Domain GTPase-Activating Protein 1 (IQGAP1) and Dishevelled (Dvl) Is Correlated with Poor Prognosis in Non-Small Cell Lung Cancer

    PubMed Central

    Zhao, Huanyu; Xie, Chengyao; Lin, Xuyong; Zhao, Yue; Han, Yang; Fan, Chuifeng; Zhang, Xiupeng; Du, Jiang; Han, Yong; Han, Qiang; Wu, Guangping; Wang, Enhua

    2014-01-01

    Background IQ-domain GTPase-activating protein 1 (IQGAP1) binds to Dishevelled (Dvl) and functions as a modulator of Dvl nuclear localization in Xenopus embryos. However, the relationship between IQGAP1 and Dvl in tumor tissues is unclear. Materials and Methods We used immunohistochemistry to assess the expressions of IQGAP1 and Dvl in a cohort of 111 non-small cell lung cancer (NSCLC) patients. Association of their localization expressions with clinicopathological factors was also analyzed. Results The positive rate of IQGAP1 in primary tumors was 48.6% (54/111) for its cytoplamic expression, 9.0% (10/111) for nuclear expression and 31.5% (35/111) for membranous expression; the positive rate of Dvl was 65.8% (73/111) for cytoplamic expression, 9.9% (11/111) for nuclear expression and 10.8% (12/111) for membranous expression. Coexpression rate of IQGAP1 and Dvl was 77.8% (42/54) in the cytoplasm, 80.0% (8/10) in the nucleus and 8.6% (3/35) in the membrane. Coexpression of IQGAP1 and Dvl in the cytoplasm and nucleus were significantly correlated (P<0.05), but not in the membrane (P>0.05). The positive expression rates of cyclin D1 and c-myc were significantly higher in the group of IQGAP1 and Dvl coexpression in the nucleus than that in the cytoplasm. Coexpression rate of IQGAP1 and Dvl in the cytoplasm and nucleus was significantly higher in lymph nodal metastases (63.3%, 19/30) than in primary growths (38.3%, 31/81), correlating with poor prognosis. Five-year survival time after resection in the group with their coexpression in the cytoplasm and nucleus was significantly lower than that with no coexpression (44.705±3.355 vs 58.403±2.543 months, p<0.05). Conclusions Coexpression of IQGAP1 and Dvl in the cytoplasm and nucleus was correlated with the lymph nodal metastase and poor prognosis of NSCLC, and coexpression in nucleus might play a critical role in the activation of canonical Wnt pathway. PMID:25436461

  7. Tenm, a Drosophila gene related to tenascin, is a new pair-rule gene.

    PubMed Central

    Baumgartner, S; Martin, D; Hagios, C; Chiquet-Ehrismann, R

    1994-01-01

    We describe the molecular characterization of the Drosophila gene tenm, a large transcription unit spanning > 110 kb of DNA. tenm encodes a large extracellular protein of 2515 amino acids related to the extracellular matrix molecule tenascin. The Tenm protein is found in seven stripes during the blastoderm stage, and each stripe overlaps with the even-skipped stripes. tenm mutants show a phenotype resembling that of odd-paired (opa), a member of the pair-rule class of segmentation genes. Thus, Tenm is the first example of a pair-rule gene product acting from outside the cell. While the Tenm protein is under the control of fushi tarazu and even-skipped, but not of opa, at least two pair-rule genes, paired (prd) and sloppy paired (slp), and all segment-polarity genes analysed to date are under the control of tenm. Our data suggest that Tenm initiates a signal transduction cascade which acts, via or in concert with opa, on downstream targets such as prd, slp, gooseberry, engrailed and wingless, leading to an opa-like phenotype. Images PMID:8070401

  8. The Drosophila anatomy ontology

    PubMed Central

    2013-01-01

    Background Anatomy ontologies are query-able classifications of anatomical structures. They provide a widely-used means for standardising the annotation of phenotypes and expression in both human-readable and programmatically accessible forms. They are also frequently used to group annotations in biologically meaningful ways. Accurate annotation requires clear textual definitions for terms, ideally accompanied by images. Accurate grouping and fruitful programmatic usage requires high-quality formal definitions that can be used to automate classification and check for errors. The Drosophila anatomy ontology (DAO) consists of over 8000 classes with broad coverage of Drosophila anatomy. It has been used extensively for annotation by a range of resources, but until recently it was poorly formalised and had few textual definitions. Results We have transformed the DAO into an ontology rich in formal and textual definitions in which the majority of classifications are automated and extensive error checking ensures quality. Here we present an overview of the content of the DAO, the patterns used in its formalisation, and the various uses it has been put to. Conclusions As a result of the work described here, the DAO provides a high-quality, queryable reference for the wild-type anatomy of Drosophila melanogaster and a set of terms to annotate data related to that anatomy. Extensive, well referenced textual definitions make it both a reliable and useful reference and ensure accurate use in annotation. Wide use of formal axioms allows a large proportion of classification to be automated and the use of consistency checking to eliminate errors. This increased formalisation has resulted in significant improvements to the completeness and accuracy of classification. The broad use of both formal and informal definitions make further development of the ontology sustainable and scalable. The patterns of formalisation used in the DAO are likely to be useful to developers of other

  9. Sexual circuitry in Drosophila.

    PubMed

    Auer, Thomas O; Benton, Richard

    2016-06-01

    The sexual behavior of Drosophila melanogaster is an outstanding paradigm to understand the molecular and neuronal basis of sophisticated animal actions. We discuss recent advances in our knowledge of the genetic hardwiring of the underlying neuronal circuitry, and how pertinent sensory cues are differentially detected and integrated in the male and female brain. We also consider how experience influences these circuits over short timescales, and the evolution of these pathways over longer timescales to endow species-specific sexual displays and responses. PMID:26851712

  10. Myoblast fusion in Drosophila

    SciTech Connect

    Haralalka, Shruti; Abmayr, Susan M.

    2010-11-01

    The body wall musculature of a Drosophila larva is composed of an intricate pattern of 30 segmentally repeated muscle fibers in each abdominal hemisegment. Each muscle fiber has unique spatial and behavioral characteristics that include its location, orientation, epidermal attachment, size and pattern of innervation. Many, if not all, of these properties are dictated by founder cells, which determine the muscle pattern and seed the fusion process. Myofibers are then derived from fusion between a specific founder cell and several fusion competent myoblasts (FCMs) fusing with as few as 3-5 FCMs in the small muscles on the most ventral side of the embryo and as many as 30 FCMs in the larger muscles on the dorsal side of the embryo. The focus of the present review is the formation of the larval muscles in the developing embryo, summarizing the major issues and players in this process. We have attempted to emphasize experimentally-validated details of the mechanism of myoblast fusion and distinguish these from the theoretically possible details that have not yet been confirmed experimentally. We also direct the interested reader to other recent reviews that discuss myoblast fusion in Drosophila, each with their own perspective on the process . With apologies, we use gene nomenclature as specified by Flybase (http://flybase.org) but provide Table 1 with alternative names and references.

  11. Initial neurogenesis in Drosophila

    PubMed Central

    Hartenstein, Volker; Wodarz, Andreas

    2014-01-01

    Early neurogenesis comprises the phase of nervous system development during which neural progenitor cells are born. In early development, the embryonic ectoderm is subdivided by a conserved signaling mechanism into two main domains, the epidermal ectoderm and the neurectoderm. Subsequently, cells of the neurectoderm are internalized and form a cell layer of proliferating neural progenitors. In vertebrates, the entire neurectoderm folds into the embryo to give rise to the neural tube. In Drosophila and many other invertebrates, a subset of neurectodermal cells, called neuroblasts (NBs), delaminates and forms the neural primordium inside the embryo where they divide in an asymmetric, stem cell-like mode. The remainder of the neuroectodermal cells that stay behind at the surface loose their neurogenic potential and later give rise to the ventral part of the epidermis. The genetic and molecular analysis of the mechanisms controlling specification and proliferation of NBs in the Drosophila embryo, which played a significant part in pioneering the field of modern developmental neurobiology, represents the topic of this review. PMID:24014455

  12. Initial neurogenesis in Drosophila.

    PubMed

    Hartenstein, Volker; Wodarz, Andreas

    2013-01-01

    Early neurogenesis comprises the phase of nervous system development during which neural progenitor cells are born. In early development, the embryonic ectoderm is subdivided by a conserved signaling mechanism into two main domains, the epidermal ectoderm and the neurectoderm. Subsequently, cells of the neurectoderm are internalized and form a cell layer of proliferating neural progenitors. In vertebrates, the entire neurectoderm folds into the embryo to give rise to the neural tube. In Drosophila and many other invertebrates, a subset of neurectodermal cells, called neuroblasts (NBs), delaminates and forms the neural primordium inside the embryo where they divide in an asymmetric, stem cell-like mode. The remainder of the neurectodermal cells that stay behind at the surface loose their neurogenic potential and later give rise to the ventral part of the epidermis. The genetic and molecular analysis of the mechanisms controlling specification and proliferation of NBs in the Drosophila embryo, which played a significant part in pioneering the field of modern developmental neurobiology, represents the topic of this review. PMID:24014455

  13. Review: Thermal preference in Drosophila

    PubMed Central

    Dillon, Michael E.; Wang, George; Garrity, Paul A.; Huey, Raymond B.

    2009-01-01

    Environmental temperature strongly affects physiology of ectotherms. Small ectotherms, like Drosophila, cannot endogenously regulate body temperature so must rely on behavior to maintain body temperature within a physiologically permissive range. Here we review what is known about Drosophila thermal preference. Work on thermal behavior in this group is particularly exciting because it provides the opportunity to connect genes to neuromolecular mechanisms to behavior to fitness in the wild. PMID:20161211

  14. Optogenetics in Drosophila Neuroscience.

    PubMed

    Riemensperger, Thomas; Kittel, Robert J; Fiala, André

    2016-01-01

    Optogenetic techniques enable one to target specific neurons with light-sensitive proteins, e.g., ion channels, ion pumps, or enzymes, and to manipulate their physiological state through illumination. Such artificial interference with selected elements of complex neuronal circuits can help to determine causal relationships between neuronal activity and the effect on the functioning of neuronal circuits controlling animal behavior. The advantages of optogenetics can best be exploited in genetically tractable animals whose nervous systems are, on the one hand, small enough in terms of cell numbers and to a certain degree stereotypically organized, such that distinct and identifiable neurons can be targeted reproducibly. On the other hand, the neuronal circuitry and the behavioral repertoire should be complex enough to enable one to address interesting questions. The fruit fly Drosophila melanogaster is a favorable model organism in this regard. However, the application of optogenetic tools to depolarize or hyperpolarize neurons through light-induced ionic currents has been difficult in adult flies. Only recently, several variants of Channelrhodopsin-2 (ChR2) have been introduced that provide sufficient light sensitivity, expression, and stability to depolarize central brain neurons efficiently in adult Drosophila. Here, we focus on the version currently providing highest photostimulation efficiency, ChR2-XXL. We exemplify the use of this optogenetic tool by applying it to a widely used aversive olfactory learning paradigm. Optogenetic activation of a population of dopamine-releasing neurons mimics the reinforcing properties of a punitive electric shock typically used as an unconditioned stimulus. In temporal coincidence with an odor stimulus this artificially induced neuronal activity causes learning of the odor signal, thereby creating a light-induced memory. PMID:26965122

  15. Why Drosophila to Study Phototransduction?

    PubMed Central

    Pak, William L.

    2010-01-01

    This review recounts the early history of Drosophila phototransduction genetics, covering the period between approximately 1966 to 1979. Early in this period, the author felt that there was an urgent need for a new approach in phototransduction research. Through inputs from a number of colleagues, he was led to consider isolating Drosophila mutants that are defective in the electroretinogram. Thanks to the efforts of dedicated associates and technical staff, by the end of this period, he was able to accumulate a large number of such mutants. Particularly important in this effort was the use of the mutant assay protocol based on the “prolonged depolarizing afterpotential.” This collection of mutants formed the basis of the subsequent intensive investigations of the Drosophila phototransduction cascade by many investigators. PMID:20536286

  16. Micromechanics of Drosophila Audition

    NASA Astrophysics Data System (ADS)

    Göpfert, M. C.; Robert, D.

    2003-02-01

    An analysis is presented of the auditory micromechanics of the fruit fly Drosophila melanogaster. In this animal, the distal part of the antenna constitutes a resonantly tuned sound receiver, the vibrations of which are transduced by a chordotonal sense organ in the antenna's base. Analyzing the mechanical behavior of the antennal receiver by means of microscanning laser Doppler vibrometry, we show that the auditory system of wild-type flies exhibits a hardening stiffness nonlinearity and spontaneously generates oscillations in the absence of external stimuli. According to the deprivation of these mechanical properties in mechanosensory mutants, the receiver's nonlinearity and oscillation activity are introduced by chordotonal auditory neurons. Requiring the mechanoreceptor-specific extracellular linker protein No-mechanoreceptor-potential-A (NompA), NompC mechanosensory transduction channels, Beethoven (Btv), and Touch-insensitive-larva-B (TilB), nonlinearity and oscillation activity of the fly's antennal receiver depend on prominent components of the auditory transduction machinery and seem to originate from motility of auditory receptor cilia.

  17. Retinal differentiation in Drosophila.

    PubMed

    Treisman, Jessica E

    2013-07-01

    Drosophila eye development has been extensively studied, due to the ease of genetic screens for mutations disrupting this process. The eye imaginal disc is specified during embryonic and larval development by the Pax6 homolog Eyeless and a network of downstream transcription factors. Expression of these factors is regulated by signaling molecules and also indirectly by growth of the eye disc. Differentiation of photoreceptor clusters initiates in the third larval instar at the posterior of the eye disc and progresses anteriorly, driven by the secreted protein Hedgehog. Within each cluster, the combined activities of Hedgehog signaling and Notch-mediated lateral inhibition induce and refine the expression of the transcription factor Atonal, which specifies the founding R8 photoreceptor of each ommatidium. Seven additional photoreceptors, followed by cone and pigment cells, are successively recruited by the signaling molecules Spitz, Delta, and Bride of sevenless. Combinations of these signals and of intrinsic transcription factors give each ommatidial cell its specific identity. During the pupal stages, rhodopsins are expressed, and the photoreceptors and accessory cells take on their final positions and morphologies to form the adult retina. Over the past few decades, the genetic analysis of this small number of cell types arranged in a repetitive structure has allowed a remarkably detailed understanding of the basic mechanisms controlling cell differentiation and morphological rearrangement. PMID:24014422

  18. Gene expression patterns in primary neuronal clusters of the Drosophila embryonic brain

    PubMed Central

    Sprecher, Simon G.; Reichert, Heinrich; Hartenstein, Volker

    2014-01-01

    The brain of Drosophila is formed by approximately 100 lineages, each lineage being derived from a stem cell-like neuroblast that segregates from the procephalic neurectoderm of the early embryo. A neuroblast map has been established in great detail for the early embryo, and a suite of molecular markers has been defined for all neuroblasts included in this map (Urbach and Technau, 2003a). However, the expression of these markers was not followed into later embryonic or larval stages, mainly due to the fact that anatomical landmarks to which expression patterns could be related had not been defined. Such markers, in the form of stereotyped clusters of neurons whose axons project along cohesive bundles (“primary axon bundles” or “PABs”) are now available (Younossi-Hartenstein et al., 2006). In the present study we have mapped the expression of molecular markers in relationship to primary neuronal clusters and their PABs. The markers we analyzed include many of the genes involved in patterning of the brain along the anteroposterior axis (cephalic gap genes, segment polarity genes) and dorso-ventral axis (columnar patterning genes), as well as genes expressed in the dorsal protocerebrum and visual system (early eye genes). Our analysis represents an important step along the way to identify neuronal lineages of the mature brain with genes expressed in the early embryo in discrete neuroblasts. Furthermore, the analysis helped us to reconstruct the morphogenetic movements that transform the two-dimensional neuroblast layer of the early embryo into the three-dimensional larval brain and provides the basis for deeper understanding of how the embryonic brain develops. PMID:17300994

  19. Antibody Staining in Drosophila Germaria.

    PubMed

    Lie-Jensen, Anette; Haglund, Kaisa

    2016-01-01

    Drosophila oogenesis is a powerful model for studying a wide spectrum of cellular and developmental processes in vivo. Oogenesis starts in a specialized structure called the germarium, which harbors the stem cells for both germ and somatic cells. The germarium produces egg chambers, each of which will develop into an egg. Active areas of research in Drosophila germaria include stem cell self-renewal, division, and maintenance, cell cycle control and differentiation, oocyte specification, intercellular communication, and signaling, among others. The solid knowledge base, the genetic tractability of the Drosophila model, as well as the availability and fast development of tools and imaging techniques for oogenesis research ensure that studies in this model will keep being instrumental for novel discoveries within cell and developmental biology also in the future. This chapter focuses on antibody staining in Drosophila germaria and provides a protocol for immunostaining as well as an overview of commonly used antibodies for visualization of different cell types and cellular structures. The protocol is well-suited for subsequent confocal microscopy analyses, and in addition we present key adaptations of the protocol that are useful when performing structured illumination microscopy (SIM) super-resolution imaging. PMID:27557571

  20. Iron Absorption in Drosophila melanogaster

    PubMed Central

    Mandilaras, Konstantinos; Pathmanathan, Tharse; Missirlis, Fanis

    2013-01-01

    The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import), the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export) and the role of ferritin in the process of iron acquisition (iron storage). We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration. PMID:23686013

  1. Iron absorption in Drosophila melanogaster.

    PubMed

    Mandilaras, Konstantinos; Pathmanathan, Tharse; Missirlis, Fanis

    2013-05-01

    The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import), the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export) and the role of ferritin in the process of iron acquisition (iron storage). We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration. PMID:23686013

  2. MUTAGENESIS SCREENING OF PESTICIDES 'DROSOPHILA'

    EPA Science Inventory

    Drosophila melanogaster males were exposed by feeding (plus contact and possibly inhalation). The genetic test found most sensitive and appropriate was the sex-linked recessive lethal test. For this, males of the Canton-S wild type stock were exposed. They were mated individually...

  3. A DNA Virus of Drosophila

    PubMed Central

    Unckless, Robert L.

    2011-01-01

    Little is known about the viruses infecting most species. Even in groups as well-studied as Drosophila, only a handful of viruses have been well-characterized. A viral metagenomic approach was used to explore viral diversity in 83 wild-caught Drosophila innubila, a mushroom feeding member of the quinaria group. A single fly that was injected with, and died from, Drosophila C Virus (DCV) was added to the sample as a control. Two-thirds of reads in the infected sample had DCV as the best BLAST hit, suggesting that the protocol developed is highly sensitive. In addition to the DCV hits, several sequences had Oryctes rhinoceros Nudivirus, a double-stranded DNA virus, as a best BLAST hit. The virus associated with these sequences was termed Drosophila innubila Nudivirus (DiNV). PCR screens of natural populations showed that DiNV was both common and widespread taxonomically and geographically. Electron microscopy confirms the presence of virions in fly fecal material similar in structure to other described Nudiviruses. In 2 species, D. innubila and D. falleni, the virus is associated with a severe (∼80–90%) loss of fecundity and significantly decreased lifespan. PMID:22053195

  4. Drosophila Photoreceptors and Signaling Mechanisms

    PubMed Central

    Katz, Ben; Minke, Baruch

    2009-01-01

    Fly eyes have been a useful biological system in which fundamental principles of sensory signaling have been elucidated. The physiological optics of the fly compound eye, which was discovered in the Musca, Calliphora and Drosophila flies, has been widely exploited in pioneering genetic and developmental studies. The detailed photochemical cycle of bistable photopigments has been elucidated in Drosophila using the genetic approach. Studies of Drosophila phototransduction using the genetic approach have led to the discovery of novel proteins crucial to many biological processes. A notable example is the discovery of the inactivation no afterpotential D scaffold protein, which binds the light-activated channel, its activator the phospholipase C and it regulator protein kinase C. An additional protein discovered in the Drosophila eye is the light-activated channel transient receptor potential (TRP), the founding member of the diverse and widely spread TRP channel superfamily. The fly eye has thus played a major role in the molecular identification of processes and proteins with prime importance. PMID:19623243

  5. Methods to assay Drosophila behavior.

    PubMed

    Nichols, Charles D; Becnel, Jaime; Pandey, Udai B

    2012-01-01

    Drosophila melanogaster, the fruit fly, has been used to study molecular mechanisms of a wide range of human diseases such as cancer, cardiovascular disease and various neurological diseases(1). We have optimized simple and robust behavioral assays for determining larval locomotion, adult climbing ability (RING assay), and courtship behaviors of Drosophila. These behavioral assays are widely applicable for studying the role of genetic and environmental factors on fly behavior. Larval crawling ability can be reliably used for determining early stage changes in the crawling abilities of Drosophila larvae and also for examining effect of drugs or human disease genes (in transgenic flies) on their locomotion. The larval crawling assay becomes more applicable if expression or abolition of a gene causes lethality in pupal or adult stages, as these flies do not survive to adulthood where they otherwise could be assessed. This basic assay can also be used in conjunction with bright light or stress to examine additional behavioral responses in Drosophila larvae. Courtship behavior has been widely used to investigate genetic basis of sexual behavior, and can also be used to examine activity and coordination, as well as learning and memory. Drosophila courtship behavior involves the exchange of various sensory stimuli including visual, auditory, and chemosensory signals between males and females that lead to a complex series of well characterized motor behaviors culminating in successful copulation. Traditional adult climbing assays (negative geotaxis) are tedious, labor intensive, and time consuming, with significant variation between different trials(2-4). The rapid iterative negative geotaxis (RING) assay(5) has many advantages over more widely employed protocols, providing a reproducible, sensitive, and high throughput approach to quantify adult locomotor and negative geotaxis behaviors. In the RING assay, several genotypes or drug treatments can be tested simultaneously

  6. Circular DNA Molecules in the Genus Drosophila

    PubMed Central

    Travaglini, E. C.; Schultz, J.

    1972-01-01

    The satellite DNA's from the embryos of five species of Drosophila (D. melanogaster, D. simulans, D. nasuta, D. virilis and D. hydei) have been analyzed for the presence of closed circular duplex DNA molecules, as determined by CsCl-EBr gradients. Circular DNA molecules were found in every species but D. melanogaster. Analyses of cell fractions from adult Drosophila and organ fractions from Drosophila larvae show that fractions containing mitochondria are highly enriched in these molecules. PMID:4643820

  7. kuzbanian-mediated cleavage of Drosophila Notch

    PubMed Central

    Lieber, Toby; Kidd, Simon; Young, Michael W.

    2002-01-01

    Loss of Kuzbanian, a member of the ADAM family of metalloproteases, produces neurogenic phenotypes in Drosophila. It has been suggested that this results from a requirement for kuzbanian-mediated cleavage of the Notch ligand Delta. Using transgenic Drosophila expressing transmembrane Notch proteins, we show that kuzbanian, independent of any role in Delta processing, is required for the cleavage of Notch. We show that Kuzbanian can physically associate with Notch and that removal of kuzbanian activity by RNA-mediated interference in Drosophila tissue culture cells eliminates processing of ligand-independent transmembrane Notch molecules. Our data suggest that in Drosophila, kuzbanian can mediate S2 cleavage of Notch. PMID:11799064

  8. A Drosophila complementary DNA resource

    SciTech Connect

    Rubin, Gerald M.; Hong, Ling; Brokstein, Peter; Evans-Holm, Martha; Frise, Erwin; Stapleton, Mark; Harvey, Damon A.

    2000-03-24

    Collections of nonredundant, full-length complementary DNA (cDNA) clones for each of the model organisms and humans will be important resources for studies of gene structure and function. We describe a general strategy for producing such collections and its implementation, which so far has generated a set of cDNAs corresponding to over 40% of the genes in the fruit fly Drosophila melanogaster.

  9. Insulin receptor in Drosophila melanogaster

    SciTech Connect

    Petruzzelli, L.; Herrera, R.; Rosen, O.

    1986-05-01

    A specific, high affinity insulin receptor is present in both adult Drosophila and in Drosophila embryos. Wheat germ lectin-enriched extracts of detergent-solubilized membranes from embryos and adults bind insulin with a K/sub d/ of 15 nM. Binding is specific for insulin; micromolar concentrations of proinsulin, IGFI, and IGFII are required to displace bound /sup 125/I-insulin. Insulin-dependent protein tyrosine kinase activity appears during embryogenesis. It is evident between 6 and 12 hours of development, peaks between 12 and 18 hours and falls in the adult. During 0-6 hours of embryogenesis, and in the adult, a specific protein band (Mr = 135,000) is crosslinked to /sup 125/I-insulin. During 6-12 and 12-18 hours of embryogenesis stages in which insulin-dependent protein tyrosine kinase is high, an additional band (Mr = 100,000) becomes crosslinked to /sup 125/I-insulin. Isolation and DNA sequence analysis of genomic clones encoding the Drosophila insulin receptor will be presented as will the characterization of insulin receptor mRNA's during development.

  10. Optogenetic pacing in Drosophila melanogaster

    PubMed Central

    Alex, Aneesh; Li, Airong; Tanzi, Rudolph E.; Zhou, Chao

    2015-01-01

    Electrical stimulation is currently the gold standard for cardiac pacing. However, it is invasive and nonspecific for cardiac tissues. We recently developed a noninvasive cardiac pacing technique using optogenetic tools, which are widely used in neuroscience. Optogenetic pacing of the heart provides high spatial and temporal precisions, is specific for cardiac tissues, avoids artifacts associated with electrical stimulation, and therefore promises to be a powerful tool in basic cardiac research. We demonstrated optogenetic control of heart rhythm in a well-established model organism, Drosophila melanogaster. We developed transgenic flies expressing a light-gated cation channel, channelrhodopsin-2 (ChR2), specifically in their hearts and demonstrated successful optogenetic pacing of ChR2-expressing Drosophila at different developmental stages, including the larva, pupa, and adult stages. A high-speed and ultrahigh-resolution optical coherence microscopy imaging system that is capable of providing images at a rate of 130 frames/s with axial and transverse resolutions of 1.5 and 3.9 μm, respectively, was used to noninvasively monitor Drosophila cardiac function and its response to pacing stimulation. The development of a noninvasive integrated optical pacing and imaging system provides a novel platform for performing research studies in developmental cardiology. PMID:26601299

  11. Leigh Syndrome in Drosophila melanogaster

    PubMed Central

    Da-Rè, Caterina; von Stockum, Sophia; Biscontin, Alberto; Millino, Caterina; Cisotto, Paola; Zordan, Mauro A.; Zeviani, Massimo; Bernardi, Paolo; De Pittà, Cristiano; Costa, Rodolfo

    2014-01-01

    Leigh Syndrome (LS) is the most common early-onset, progressive mitochondrial encephalopathy usually leading to early death. The single most prevalent cause of LS is occurrence of mutations in the SURF1 gene, and LSSurf1 patients show a ubiquitous and specific decrease in the activity of mitochondrial respiratory chain complex IV (cytochrome c oxidase, COX). SURF1 encodes an inner membrane mitochondrial protein involved in COX assembly. We established a Drosophila melanogaster model of LS based on the post-transcriptional silencing of CG9943, the Drosophila homolog of SURF1. Knockdown of Surf1 was induced ubiquitously in larvae and adults, which led to lethality; in the mesodermal derivatives, which led to pupal lethality; or in the central nervous system, which allowed survival. A biochemical characterization was carried out in knockdown individuals, which revealed that larvae unexpectedly displayed defects in all complexes of the mitochondrial respiratory chain and in the F-ATP synthase, while adults had a COX-selective impairment. Silencing of Surf1 expression in Drosophila S2R+ cells led to selective loss of COX activity associated with decreased oxygen consumption and respiratory reserve. We conclude that Surf1 is essential for COX activity and mitochondrial function in D. melanogaster, thus providing a new tool that may help clarify the pathogenic mechanisms of LS. PMID:25164807

  12. 'Peer pressure' in larval Drosophila?

    PubMed

    Niewalda, Thomas; Jeske, Ines; Michels, Birgit; Gerber, Bertram

    2014-01-01

    Understanding social behaviour requires a study case that is simple enough to be tractable, yet complex enough to remain interesting. Do larval Drosophila meet these requirements? In a broad sense, this question can refer to effects of the mere presence of other larvae on the behaviour of a target individual. Here we focused in a more strict sense on 'peer pressure', that is on the question of whether the behaviour of a target individual larva is affected by what a surrounding group of larvae is doing. We found that innate olfactory preference of a target individual was neither affected (i) by the level of innate olfactory preference in the surrounding group nor (ii) by the expression of learned olfactory preference in the group. Likewise, learned olfactory preference of a target individual was neither affected (iii) by the level of innate olfactory preference of the surrounding group nor (iv) by the learned olfactory preference the group was expressing. We conclude that larval Drosophila thus do not take note of specifically what surrounding larvae are doing. This implies that in a strict sense, and to the extent tested, there is no social interaction between larvae. These results validate widely used en mass approaches to the behaviour of larval Drosophila. PMID:24907371

  13. Biology and physiology of Drosophila suzukii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spotted wing drosophila, Drosophila suzukii, quickly emerged as a devastating invasive pest of small and stone fruits in the Americas and Europe. To better understand the population dynamics of D. suzukii, we reviewed recent work on juvenile development, adult reproduction, and seasonal variation in...

  14. Drosophila and Beer: An Experimental Laboratory Exercise

    ERIC Educational Resources Information Center

    Kurvink, Karen

    2004-01-01

    Drosophila melanogaster is a popular organism for studying genetics and development. Maintaining Drosophila on medium prepared with varying concentrations of beer and evaluating the effects on reproduction, life cycle stages and other factors is one of the exercises that is versatile and applicable to many student levels.

  15. Taste processing in Drosophila larvae

    PubMed Central

    Apostolopoulou, Anthi A.; Rist, Anna; Thum, Andreas S.

    2015-01-01

    The sense of taste allows animals to detect chemical substances in their environment to initiate appropriate behaviors: to find food or a mate, to avoid hostile environments and predators. Drosophila larvae are a promising model organism to study gustation. Their simple nervous system triggers stereotypic behavioral responses, and the coding of taste can be studied by genetic tools at the single cell level. This review briefly summarizes recent progress on how taste information is sensed and processed by larval cephalic and pharyngeal sense organs. The focus lies on several studies, which revealed cellular and molecular mechanisms required to process sugar, salt, and bitter substances. PMID:26528147

  16. Cryobiological preservation of Drosophila embryos

    SciTech Connect

    Mazur, P.; Schreuders, P.D.; Cole, K.W.; Hall, J.W. ); Mahowald, A.P. )

    1992-12-18

    The inability to cryobiologically preserve the fruit fly Drosophila melanogaster has required that fly stocks be maintained by frequent transfer of adults. This method is costly in terms of time and can lead to loss of stocks. Traditional slow freezing methods do not succeed because the embryos are highly sensitive to chilling. With the procedures described here, 68 percent of precisely staged 15-hour Oregon R (wild-type) embryos hatch after vitrification at -205[degree]C, and 40 percent of the resulting larvae develop into normal adult flies. These embryos are among the most complex organisms successfully preserved by cryobiology.

  17. Geotaxis baseline data for Drosophila

    NASA Technical Reports Server (NTRS)

    Schnebel, E. M.; Bhargava, R.; Grossfield, J.

    1987-01-01

    Geotaxis profiles for 20 Drosophila species and semispecies at different ages have been examined using a calibrated, adjustable slant board device. Measurements were taken at 5 deg intervals ranging from 0 deg to 85 deg. Clear strain and species differences are observed, with some groups tending to move upward (- geotaxis) with increasing angles, while others move downward (+ geotaxis). Geotactic responses change with age in some, but not all experimental groups. Sample geotaxis profiles are presented and their application to ecological and aging studies are discussed. Data provide a baseline for future evaluations of the biological effects of microgravity.

  18. Macrophages and cellular immunity in Drosophila melanogaster.

    PubMed

    Gold, Katrina S; Brückner, Katja

    2015-12-01

    The invertebrate Drosophila melanogaster has been a powerful model for understanding blood cell development and immunity. Drosophila is a holometabolous insect, which transitions through a series of life stages from embryo, larva and pupa to adulthood. In spite of this, remarkable parallels exist between Drosophila and vertebrate macrophages, both in terms of development and function. More than 90% of Drosophila blood cells (hemocytes) are macrophages (plasmatocytes), making this highly tractable genetic system attractive for studying a variety of questions in macrophage biology. In vertebrates, recent findings revealed that macrophages have two independent origins: self-renewing macrophages, which reside and proliferate in local microenvironments in a variety of tissues, and macrophages of the monocyte lineage, which derive from hematopoietic stem or progenitor cells. Like vertebrates, Drosophila possesses two macrophage lineages with a conserved dual ontogeny. These parallels allow us to take advantage of the Drosophila model when investigating macrophage lineage specification, maintenance and amplification, and the induction of macrophages and their progenitors by local microenvironments and systemic cues. Beyond macrophage development, Drosophila further serves as a paradigm for understanding the mechanisms underlying macrophage function and cellular immunity in infection, tissue homeostasis and cancer, throughout development and adult life. PMID:27117654

  19. Cellular immune defenses of Drosophila melanogaster.

    PubMed

    Parsons, Brendon; Foley, Edan

    2016-05-01

    Drosophila melanogaster is a widely used model for the characterization of blood cell development and function, with an array of protocols for the manipulation and visualization of fixed or live cells in vitro or in vivo. Researchers have deployed these techniques to reveal Drosophila hemocytes as a remarkably versatile cell type that engulfs apoptotic corpses; neutralizes invading parasites; seals epithelial wounds; and deposits extracellular matrix proteins. In this review, we will discuss the key features of Drosophila hemocyte development and function, and identify similarities with vertebrate counterparts. PMID:26748247

  20. Complete mitochondrial genome of Drosophila albomicans.

    PubMed

    Kang, Xiongbin; Luo, Xiao; Zhang, Zhi; Zhang, Zhen; Yang, Junqing; Bi, Guiqi

    2016-09-01

    Drosophila albomicans has been widely used as an important animal model for chromosome evolution. In this study, the mitochondrial genome sequence of this species is determined and described for the first time. The mitochondrial genome (15 849 bp) encompasses two rRNA, 22 tRNA, and 13 protein-coding genes. Genome content and structure are similar to those reported from other Drosophila mitochondrial genomes. Phylogeny analysis indicates that D. albomicans have a closer genetic relationship with Drosophil aincompta and Drosophil alittoralis. This mitochondrial genome is potentially important for studying molecular evolution and conservation genetics in Drosophila genus. PMID:26358579

  1. Drosophila Modeling of Heritable Neurodevelopmental Disorders

    PubMed Central

    Gatto, Cheryl L.; Broadie, Kendal

    2011-01-01

    Heritable neurodevelopmental disorders are multifaceted disease conditions encompassing a wide range of symptoms including intellectual disability, cognitive dysfunction, autism and myriad other behavioral impairments. In cases where single, causative genetic defects have been identified, such as Angelman syndrome, Rett syndrome, Neurofibromatosis Type 1 and Fragile X syndrome, the classical Drosophila genetic system has provided fruitful disease models. Recent Drosophila studies have advanced our understanding of UBE3A, MECP2, NF1 and FMR1 function, respectively, in genetic, biochemical, anatomical, physiological and behavioral contexts. Investigations in Drosophila continue to provide the essential mechanistic understanding required to facilitate the conception of rational therapeutic treatments. PMID:21596554

  2. Drosophila Models of Cardiac Disease

    PubMed Central

    Piazza, Nicole; Wessells, R.J.

    2013-01-01

    The fruit fly Drosophila melanogaster has emerged as a useful model for cardiac diseases, both developmental abnormalities and adult functional impairment. Using the tools of both classical and molecular genetics, the study of the developing fly heart has been instrumental in identifying the major signaling events of cardiac field formation, cardiomyocyte specification, and the formation of the functioning heart tube. The larval stage of fly cardiac development has become an important model system for testing isolated preparations of living hearts for the effects of biological and pharmacological compounds on cardiac activity. Meanwhile, the recent development of effective techniques to study adult cardiac performance in the fly has opened new uses for the Drosophila model system. The fly system is now being used to study long-term alterations in adult performance caused by factors such as diet, exercise, and normal aging. The fly is a unique and valuable system for the study of such complex, long-term interactions, as it is the only invertebrate genetic model system with a working heart developmentally homologous to the vertebrate heart. Thus, the fly model combines the advantages of invertebrate genetics (such as large populations, facile molecular genetic techniques, and short lifespan) with physiological measurement techniques that allow meaningful comparisons with data from vertebrate model systems. As such, the fly model is well situated to make important contributions to the understanding of complicated interactions between environmental factors and genetics in the long-term regulation of cardiac performance. PMID:21377627

  3. Automated Tracking of Drosophila Specimens

    PubMed Central

    Chao, Rubén; Macía-Vázquez, Germán; Zalama, Eduardo; Gómez-García-Bermejo, Jaime; Perán, José-Ramón

    2015-01-01

    The fruit fly Drosophila Melanogaster has become a model organism in the study of neurobiology and behavior patterns. The analysis of the way the fly moves and its behavior is of great scientific interest for research on aspects such as drug tolerance, aggression or ageing in humans. In this article, a procedure for detecting, identifying and tracking numerous specimens of Drosophila by means of computer vision-based sensing systems is presented. This procedure allows dynamic information about each specimen to be collected at each moment, and then for its behavior to be quantitatively characterized. The proposed algorithm operates in three main steps: a pre-processing step, a detection and segmentation step, and tracking shape. The pre-processing and segmentation steps allow some limits of the image acquisition system and some visual artifacts (such as shadows and reflections) to be dealt with. The improvements introduced in the tracking step allow the problems corresponding to identity loss and swaps, caused by the interaction between individual flies, to be solved efficiently. Thus, a robust method that compares favorably to other existing methods is obtained. PMID:26258779

  4. Automated Tracking of Drosophila Specimens.

    PubMed

    Chao, Rubén; Macía-Vázquez, Germán; Zalama, Eduardo; Gómez-García-Bermejo, Jaime; Perán, José-Ramón

    2015-01-01

    The fruit fly Drosophila Melanogaster has become a model organism in the study of neurobiology and behavior patterns. The analysis of the way the fly moves and its behavior is of great scientific interest for research on aspects such as drug tolerance, aggression or ageing in humans. In this article, a procedure for detecting, identifying and tracking numerous specimens of Drosophila by means of computer vision-based sensing systems is presented. This procedure allows dynamic information about each specimen to be collected at each moment, and then for its behavior to be quantitatively characterized. The proposed algorithm operates in three main steps: a pre-processing step, a detection and segmentation step, and tracking shape. The pre-processing and segmentation steps allow some limits of the image acquisition system and some visual artifacts (such as shadows and reflections) to be dealt with. The improvements introduced in the tracking step allow the problems corresponding to identity loss and swaps, caused by the interaction between individual flies, to be solved efficiently. Thus, a robust method that compares favorably to other existing methods is obtained. PMID:26258779

  5. Monoamines and sleep in Drosophila.

    PubMed

    Nall, Aleksandra; Sehgal, Amita

    2014-06-01

    Sleep is an important physiological state, but its function and regulation remain elusive. Drosophila melanogaster is a useful model organism for studying sleep because it has a well-established diurnal activity pattern, including consolidated periods of quiescence that share many characteristics with human sleep. Sleep behavior is regulated by circadian and homeostatic processes and is modulated by environmental and physiological context cues. These cues are communicated to sleep circuits by neurohormones and neuromodulators. A major class of neuromodulators, monoamines, has been found to be essential in various aspects of sleep regulation. Dopamine promotes arousal and sleep-dependent memory formation as well as daily activity. Octopamine, the insect homolog of norepinephrine, promotes wake and may play a role in circadian clock-dependent sleep and arousal. Serotonin promotes sleep and modulates circadian entrainment to light. The different monoamines each signal through multiple receptors in various brain regions in response to different conditions. How these separate circuits integrate their inputs into a single program of behavior is an open field of study for which Drosophila will continue to be a useful model. Monoamine biosynthetic pathways and receptors are conserved between flies and humans, and, thus far, their roles in modulating sleep also appear to be conserved. PMID:24886188

  6. Ecdysteroid receptors in Drosophila melanogaster adult females

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ecdysteroid receptors were identified and partially characterized from total cell extracts of whole animals and dissected tissues from Drosophila melanogaster adult females. Binding studies indicated the presence of two ecdysteroid binding components having high affinity and specificity consistent w...

  7. Colour vision: parallel pathways intersect in Drosophila.

    PubMed

    Kelber, Almut; Henze, Miriam J

    2013-12-01

    In the last one hundred years, colour vision has been demonstrated in bees and many other insects. But the underlying neural wiring remained elusive. A new study on Drosophila melanogaster combining behavioural and genetic tools yields surprising insights. PMID:24309280

  8. Gene Regulation Networks for Modeling Drosophila Development

    NASA Technical Reports Server (NTRS)

    Mjolsness, E.

    1999-01-01

    This chapter will very briefly introduce and review some computational experiments in using trainable gene regulation network models to simulate and understand selected episodes in the development of the fruit fly, Drosophila Melanogaster.

  9. Drosophila RNAi screening in a postgenomic world

    PubMed Central

    2011-01-01

    Drosophila melanogaster has a long history as a model organism with several unique features that make it an ideal research tool for the study of the relationship between genotype and phenotype. Importantly fundamental genetic principles as well as key human disease genes have been uncovered through the use of Drosophila. The contribution of the fruit fly to science and medicine continues in the postgenomic era as cell-based Drosophila RNAi screens are a cost-effective and scalable enabling technology that can be used to quantify the contribution of different genes to diverse cellular processes. Drosophila high-throughput screens can also be used as integral part of systems-level approaches to describe the architecture and dynamics of cellular networks. PMID:21752787

  10. Drosophila Cajal bodies: accessories not included

    PubMed Central

    Matera, A. Gregory

    2006-01-01

    Cajal bodies are nuclear sites of small ribonucleoprotein (RNP) remodeling and maturation. A recent study describes the discovery of the Drosophila Cajal body, revealing some interesting insights into the subnuclear organization of RNA processing machineries among different species. PMID:16533940

  11. Targeted genome engineering techniques in Drosophila

    PubMed Central

    Beumer, Kelly J.; Carroll, Dana

    2014-01-01

    For a century, Drosophila has been a favored organism for genetic research. However, the array of materials and methods available to the Drosophila worker has expanded dramatically in the last decade. The most common gene targeting tools, zinc finger nucleases, TALENs, and RNA-guided CRISPR/Cas9, have all been adapted for use in Drosophila, both for simple mutagenesis and for gene editing via homologous recombination. For each tool, there exist a number of web sites, design applications, and delivery methods. The successful application of any of these tools also requires an understanding of methods for detecting successful genome modifications. This article provides an overview of the available gene targeting tools and their application in Drosophila. In lieu of simply providing a protocol for gene targeting, we direct the researcher to resources that will allow access to the latest research in this rapidly evolving field. PMID:24412316

  12. Circadian light-input pathways in Drosophila.

    PubMed

    Yoshii, Taishi; Hermann-Luibl, Christiane; Helfrich-Förster, Charlotte

    2016-01-01

    Light is the most important environmental cue to entrain the circadian clock in most animals. In the fruit fly Drosophila melanogaster, the light entrainment mechanisms of the clock have been well-studied. The Drosophila brain contains approximately 150 neurons that rhythmically express circadian clock genes. These neurons are called "clock neurons" and control behavioral activity rhythms. Many clock neurons express the Cryptochrome (CRY) protein, which is sensitive to UV and blue light, and thus enables clock neurons deep in the brain to directly perceive light. In addition to the CRY protein, external photoreceptors in the Drosophila eyes play an important role in circadian light-input pathways. Recent studies have provided new insights into the mechanisms that integrate these light inputs into the circadian network of the brain. In this review, we will summarize the current knowledge on the light entrainment pathways in the Drosophila circadian clock. PMID:27066180

  13. A Drosophila Model for Screening Antiobesity Agents

    PubMed Central

    Men, Tran Thanh; Thanh, Duong Ngoc Van; Yamaguchi, Masamitsu; Suzuki, Takayoshi; Hattori, Gen; Arii, Masayuki; Huy, Nguyen Tien; Kamei, Kaeko

    2016-01-01

    Although triacylglycerol, the major component for lipid storage, is essential for normal physiology, its excessive accumulation causes obesity in adipose tissue and is associated with organ dysfunction in nonadipose tissue. Here, we focused on the Drosophila model to develop therapeutics for preventing obesity. The brummer (bmm) gene in Drosophila melanogaster is known to be homologous with human adipocyte triglyceride lipase, which is related to the regulation of lipid storage. We established a Drosophila model for monitoring bmm expression by introducing the green fluorescent protein (GFP) gene as a downstream reporter of the bmm promoter. The third-instar larvae of Drosophila showed the GFP signal in all tissues observed and specifically in the salivary gland nucleus. To confirm the relationship between bmm expression and obesity, the effect of oral administration of glucose diets on bmm promoter activity was analyzed. The Drosophila flies given high-glucose diets showed higher lipid contents, indicating the obesity phenotype; this was suggested by a weaker intensity of the GFP signal as well as reduced bmm mRNA expression. These results demonstrated that the transgenic Drosophila model established in this study is useful for screening antiobesity agents. We also report the effects of oral administration of histone deacetylase inhibitors and some vegetables on the bmm promoter activity. PMID:27247940

  14. Two retrotransposons maintain telomeres in Drosophila

    PubMed Central

    Pardue, M.-L.; Rashkova, S.; Casacuberta, E.; DeBaryshe, P.G.; George, J. A.; Traverse, K.L.

    2005-01-01

    Telomeres across the genus Drosophila are maintained, not by telomerase, but by two non-LTR retrotransposons, HeT-A and TART, that transpose specifically to chromosome ends. Successive transpositions result in long head-to-tail arrays of these elements. Thus Drosophila telomeres, like those produced by telomerase, consist of repeated sequences reverse transcribed from RNA templates. The Drosophila repeats, complete and 5′-truncated copies of HeT-A and TART, are more complex than telomerase repeats; nevertheless these evolutionary variants have functional similarities to the more common telomeres. Like other telomeres, the Drosophila arrays are dynamic, fluctuating around an average length that can be changed by changes in the genetic background. Several proteins that interact with telomeres in other species have been found to have homologues that interact with Drosophila telomeres. Although they have hallmarks of non-LTR retrotransposons, HeT-A and TART appear to have a special relationship to Drosophila. Their Gag proteins are efficiently transported into diploid nuclei where HeT-A Gag recruits TART Gag to chromosome ends. Gags of other non-LTR elements remain predominantly in the cytoplasm. These studies provide intriguing evolutionary links between telomeres and retrotransposable elements. PMID:16132810

  15. Current Recommendations for Managing Spotted Wing Drosophila (SWD), Drosophila suzukii, in PNW Caneberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spotted wing Drosophila (SWD), Drosophila suzukii, was reported in the Pacific Northwest (Oregon, Washington, British Columbia) in 2009. The fly is able to oviposit directly into intact ripe and ripening fruit, so it is of great economic concern to the small fruit industries in region. Fruit i...

  16. The susceptibility of small fruits and cherries to Spotted Wing Drosophila, Drosophila suzukii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: The Spotted Wing Drosophila (SWD), Drosophila suzukii Matsumura, is native to Asia and has been detected in the North American mainland and Europe in 2008-10. SWD is a serious economic pest because it lays eggs within ripening fruit before harvest which can lead to crop loss. The aim ...

  17. Behavioral and antennal responses of spotted wing drosophila, drosophila suzukii, to volatiles from fruit extracts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Native to Southeast Asia, the spotted wing drosophila, Drosophila suzukii, has become a serious pest of soft-skinned fruit crops since its introduction into North America and Europe in 2008. Current monitoring strategies use baits based on fermentation products; however, to date, no fruit-based vola...

  18. Postharvest treatment of strawberries with methyl bromide to control spotted wing drosophila, Drosophila suzukii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spotted wing drosophila (SWD), Drosophila suzukii, is a pest of concern to countries that import strawberries from California USA. The purpose of this investigation was to verify elimination of SWD in California-grown fresh strawberries under conditions consistent with export to Australia; a 3-h fum...

  19. Current Recommendations for Managing Spotted Wing Drosophila (SWD), Drosophila suzukii, in PNW Strawberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spotted wing Drosophila (SWD), Drosophila suzukii, was reported in the Pacific Northwest (Oregon, Washington, British Columbia) in 2009. The fly is able to oviposit directly into intact ripe and ripening fruit, so it is of great economic concern to the small fruit industries in region. Fruit i...

  20. Current Recommendations for Managing Spotted Wing Drosophila (SWD), Drosophila suzukii, in PNW Blueberries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spotted wing Drosophila (SWD), Drosophila suzukii, was reported in the Pacific Northwest (Oregon, Washington, British Columbia) in 2009. The fly is able to oviposit directly into intact ripe and ripening fruit, so it is of great economic concern to the small fruit industries in region. Fruit i...

  1. Invasion biology of Spotted Wing Drosophila (Drosophila suzukii): a global perspective and future priorities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Asian vinegar fly species Drosophila suzukii (spotted-wing Drosophila or SWD) has emerged as an important invasive insect pest of small and stone fruits in both the Americas and Europe since the late 2000’s. While research efforts have rapidly progressed in Asia, North America, and Europe over ...

  2. Spotted wing drosophila, Drosophila suzukii (Matsumura)(Diptera: drosophilidae), trapped with combinations of wines and vinegars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field trapping experiments evaluated wine and vinegar baits for spotted wing drosophila flies, Drosophila suzukii (Matsumura), and assessed variance in biat attractiveness with wit type, vinegar type, and bait age. A mixture of apple cider vinegar and a Merlot wine attracted more flies than a mixtur...

  3. Homotypic Regulatory Clusters in Drosophila

    PubMed Central

    Lifanov, Alexander P.; Makeev, Vsevolod J.; Nazina, Anna G.; Papatsenko, Dmitri A.

    2003-01-01

    Cis-regulatory modules (CRMs) are transcription regulatory DNA segments (∼1 Kb range) that control the expression of developmental genes in higher eukaryotes. We analyzed clustering of known binding motifs for transcription factors (TFs) in over 60 known CRMs from 20 Drosophila developmental genes, and we present evidence that each type of recognition motif forms significant clusters within the regulatory regions regulated by the corresponding TF. We demonstrate how a search with a single binding motif can be applied to explore gene regulatory networks and to discover coregulated genes in the genome. We also discuss the potential of the clustering method in interpreting the differential response of genes to various levels of transcriptional regulators. PMID:12670999

  4. Investigating Spermatogenesis in Drosophila melanogaster

    PubMed Central

    Demarco, Rafael S.; Eikenes, Åsmund H.; Haglund, Kaisa; Jones, D. Leanne

    2014-01-01

    The process of spermatogenesis in Drosophila melanogaster provides a powerful model system to probe a variety of developmental and cell biological questions, such as the characterization of mechanisms that regulate stem cell behavior, cytokinesis, meiosis, and mitochondrial dynamics. Classical genetic approaches, together with binary expression systems, FRT-mediated recombination, and novel imaging systems to capture single cell behavior, are rapidly expanding our knowledge of the molecular mechanisms regulating all aspects of spermatogenesis. This methods chapter provides a detailed description of the system, a review of key questions chapter that have been addressed or remain unanswered thus far, and an introduction to tools and techniques available to probe each stage of spermatogenesis. PMID:24798812

  5. Resources for Biological Annotation of the Drosophila Genome

    SciTech Connect

    Gerald M. Rubin

    2005-08-08

    This project supported seed money for the development of cDNA and genetic resources to support studies of the Drosophila melanogaster genome. Key publications supported by this work that provide additional detail: (1) ''The Drosophila gene collection: identification of putative full-length cDNAs for 70% of D. melanogaster genes''; and (2) ''The Berkeley Drosophila Genome Project gene disruption project: Single P-element insertions mutating 25% of vital Drosophila genes''.

  6. Enhancing Undergraduate Teaching and Research with a "Drosophila" Virginizing System

    ERIC Educational Resources Information Center

    Venema, Dennis R.

    2006-01-01

    Laboratory exercises using "Drosophila" crosses are an effective pedagogical method to complement traditional lecture and textbook presentations of genetics. Undergraduate thesis research is another common setting for using "Drosophila." A significant barrier to using "Drosophila" for undergraduate teaching or research is the time and skill…

  7. Environmental ethanol as an ecological constraint on dietary breadth of Spotted-Wing Drosophila, Drosophila suzukii Mat. (Diptera: Drosophilidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spotted-wing Drosophila (SWD), Drosophila suzukii, is a recent fruit pest of the Americas whose destructiveness stems from its subcutaneous insertion of eggs into cultivated berries via a female’s prominent double bladed and serrated ovipositor. Atypical of most other Drosophila, D. suzukii adults a...

  8. Development of dendrite polarity in Drosophila neurons

    PubMed Central

    2012-01-01

    Background Drosophila neurons have dendrites that contain minus-end-out microtubules. This microtubule arrangement is different from that of cultured mammalian neurons, which have mixed polarity microtubules in dendrites. Results To determine whether Drosophila and mammalian dendrites have a common microtubule organization during development, we analyzed microtubule polarity in Drosophila dendritic arborization neuron dendrites at different stages of outgrowth from the cell body in vivo. As dendrites initially extended, they contained mixed polarity microtubules, like mammalian neurons developing in culture. Over a period of several days this mixed microtubule array gradually matured to a minus-end-out array. To determine whether features characteristic of dendrites were localized before uniform polarity was attained, we analyzed dendritic markers as dendrites developed. In all cases the markers took on their characteristic distribution while dendrites had mixed polarity. An axonal marker was also quite well excluded from dendrites throughout development, although this was perhaps more efficient in mature neurons. To confirm that dendrite character could be acquired in Drosophila while microtubules were mixed, we genetically disrupted uniform dendritic microtubule organization. Dendritic markers also localized correctly in this case. Conclusions We conclude that developing Drosophila dendrites initially have mixed microtubule polarity. Over time they mature to uniform microtubule polarity. Dendrite identity is established before the mature microtubule arrangement is attained, during the period of mixed microtubule polarity. PMID:23111238

  9. 31 Flavors of Drosophila Rab proteins

    SciTech Connect

    Zhang, Jun; Schulze, Karen L.; Hiesinger, P. Robin; Suyama, Kaye; Wang, Stream; Fish, Matthew; Acar, Melih; Hoskins, Roger A.; Bellen, HugoJ.; Scott, Matthew P.

    2007-04-03

    Rab proteins are small GTPases that play important roles intransport of vesicle cargo and recruitment, association of motor andother proteins with vesicles, and docking and fusion of vesicles atdefined locations. In vertebrates, more than 75 Rab genes have beenidentified, some of which have been intensively studied for their rolesin endosome and synaptic vesicle trafficking. Recent studies of thefunctions of certain Rab proteins have revealed specific roles inmediating developmental signal transduction. We have begun a systematicgenetic study of the 33 Rab genes in Drosophila. Most of the fly proteinsare clearly related to specific vertebrate proteins. We report here thecreation of a set of transgenic fly lines that allow spatially andtemporally regulated expression of Drosophila Rab proteins. We generatedfluorescent protein-tagged wild-type, dominant-negative, andconstitutively active forms of 31 Drosophila Rab proteins. We describeDrosophila Rab expression patterns during embryogenesis, the subcellularlocalization of some Rab proteins, and comparisons of the localization ofwild-type, dominant-negative, and constitutively active forms of selectedRab proteins. The high evolutionary conservation and low redundancy ofDrosophila Rab proteins make these transgenic lines a useful toolkit forinvestigating Rab functions in vivo.

  10. Gut-associated microbes of Drosophila melanogaster

    PubMed Central

    Broderick, Nichole; Lemaitre, Bruno

    2012-01-01

    There is growing interest in using Drosophila melanogaster to elucidate mechanisms that underlie the complex relationships between a host and its microbiota. In addition to the many genetic resources and tools Drosophila provides, its associated microbiota is relatively simple (1–30 taxa), in contrast to the complex diversity associated with vertebrates (> 500 taxa). These attributes highlight the potential of this system to dissect the complex cellular and molecular interactions that occur between a host and its microbiota. In this review, we summarize what is known regarding the composition of gut-associated microbes of Drosophila and their impact on host physiology. We also discuss these interactions in the context of their natural history and ecology and describe some recent insights into mechanisms by which Drosophila and its gut microbiota interact. “Workers with Drosophila have been considered fortunate in that they deal with the first multicellular invertebrate to be cultured monoxenically (Delcourt and Guyenot, 1910); the first to be handled axenically on a semisynthetic diet (Guyenot, 1917); and the first to be grown on a defined diet (Schultz et al., 1946). This list of advantages is somewhat embarrassing, since it implies an interest in nutrition that, in reality, was only secondary. The very first studies were concerned with the reduction of variability in genetic experiments (Delcourt and Guyenot, 1910) and standardization of the nutritional environment.” -James Sang, 1959 Ann NY Acad 1 PMID:22572876

  11. The digestive tract of Drosophila melanogaster.

    PubMed

    Lemaitre, Bruno; Miguel-Aliaga, Irene

    2013-01-01

    The digestive tract plays a central role in the digestion and absorption of nutrients. Far from being a passive tube, it provides the first line of defense against pathogens and maintains energy homeostasis by exchanging neuronal and endocrine signals with other organs. Historically neglected, the gut of the fruit fly Drosophila melanogaster has recently come to the forefront of Drosophila research. Areas as diverse as stem cell biology, neurobiology, metabolism, and immunity are benefitting from the ability to study the genetics of development, growth regulation, and physiology in the same organ. In this review, we summarize our knowledge of the Drosophila digestive tract, with an emphasis on the adult midgut and its functional underpinnings. PMID:24016187

  12. Viruses and Antiviral Immunity in Drosophila

    PubMed Central

    Xu, Jie; Cherry, Sara

    2013-01-01

    Viral pathogens present many challenges to organisms, driving the evolution of a myriad of antiviral strategies to combat infections. A wide variety of viruses infect invertebrates, including both natural pathogens that are insect-restricted, and viruses that are transmitted to vertebrates. Studies using the powerful tools available in the model organism Drosophila have expanded our understanding of antiviral defenses against diverse viruses. In this review, we will cover three major areas. First, we will describe the tools used to study viruses in Drosophila. Second, we will survey the major viruses that have been studied in Drosophila. And lastly, we will discuss the well-characterized mechanisms that are active against these diverse pathogens, focusing on non-RNAi mediated antiviral mechanisms. Antiviral RNAi is discussed in another paper in this issue. PMID:23680639

  13. Apoptosis in Drosophila: which role for mitochondria?

    PubMed

    Clavier, Amandine; Rincheval-Arnold, Aurore; Colin, Jessie; Mignotte, Bernard; Guénal, Isabelle

    2016-03-01

    It is now well established that the mitochondrion is a central regulator of mammalian cell apoptosis. However, the importance of this organelle in non-mammalian apoptosis has long been regarded as minor, mainly because of the absence of a crucial role for cytochrome c in caspase activation. Recent results indicate that the control of caspase activation and cell death in Drosophila occurs at the mitochondrial level. Numerous proteins, including RHG proteins and proteins of the Bcl-2 family that are key regulators of Drosophila apoptosis, constitutively or transiently localize in mitochondria. These proteins participate in the cell death process at different levels such as degradation of Diap1, a Drosophila IAP, production of mitochondrial reactive oxygen species or stimulation of the mitochondrial fission machinery. Here, we review these mitochondrial events that might have their counterpart in human. PMID:26679112

  14. Xotch, the Xenopus homolog of Drosophila notch.

    PubMed

    Coffman, C; Harris, W; Kintner, C

    1990-09-21

    During the development of a vertebrate embryo, cell fate is determined by inductive signals passing between neighboring tissues. Such determinative interactions have been difficult to characterize fully without knowledge of the molecular mechanisms involved. Mutations of Drosophila and the nematode Caenorhabditis elegans have been isolated that define a family of related gene products involved in similar types of cellular inductions. One of these genes, the Notch gene from Drosophila, is involved with cell fate choices in the neurogenic region of the blastoderm, in the developing nervous system, and in the eye-antennal imaginal disc. Complementary DNA clones were isolated from Xenopus embryos with Notch DNA in order to investigate whether cell-cell interactions in vertebrate embryos also depend on Notch-like molecules. This approach identified a Xenopus molecule, Xotch, which is remarkably similar to Drosophila Notch in both structure and developmental expression. PMID:2402639

  15. Receptor Tyrosine Kinases in Drosophila Development

    PubMed Central

    Sopko, Richelle; Perrimon, Norbert

    2013-01-01

    Tyrosine phosphorylation plays a significant role in a wide range of cellular processes. The Drosophila genome encodes more than 20 receptor tyrosine kinases and extensive studies in the past 20 years have illustrated their diverse roles and complex signaling mechanisms. Although some receptor tyrosine kinases have highly specific functions, others strikingly are used in rather ubiquitous manners. Receptor tyrosine kinases regulate a broad expanse of processes, ranging from cell survival and proliferation to differentiation and patterning. Remarkably, different receptor tyrosine kinases share many of the same effectors and their hierarchical organization is retained in disparate biological contexts. In this comprehensive review, we summarize what is known regarding each receptor tyrosine kinase during Drosophila development. Astonishingly, very little is known for approximately half of all Drosophila receptor tyrosine kinases. PMID:23732470

  16. Developmental Toxicity Assays Using the Drosophila Model

    PubMed Central

    Rand, Matthew D.; Montgomery, Sara L.; Prince, Lisa; Vorojeikina, Daria

    2014-01-01

    The fruit fly (Drosophila melanogaster) has long been a premier model for developmental biologists and geneticists. The utility of Drosophila for toxicology studies has only recently gained broader recognition as a tool to elaborate molecular genetic mechanisms of toxic substances. In this article two practical applications of Drosophila for developmental toxicity assays are described. The first assay takes advantage of newly developed methods to render the fly embryo accessible to small molecules, toxicants and drugs. The second assay engages straightforward exposures to developing larvae and easy to score outcomes of adult development. With the extensive collections of flies that are publicly available and the ease with which to create transgenic flies, these two assays have a unique power for identifying and characterizing molecular mechanisms and cellular pathways specific to the mode of action of a number of toxicants and drugs. PMID:24789363

  17. Live cell imaging in Drosophila melanogaster.

    PubMed

    Parton, Richard M; Vallés, Ana Maria; Dobbie, Ian M; Davis, Ilan

    2010-04-01

    Although many of the techniques of live cell imaging in Drosophila melanogaster are also used by the greater community of cell biologists working on other model systems, studying living fly tissues presents unique difficulties with regard to keeping the cells alive, introducing fluorescent probes, and imaging through thick, hazy cytoplasm. This article outlines the major tissue types amenable to study by time-lapse cinematography and different methods for keeping the cells alive. It describes various imaging and associated techniques best suited to following changes in the distribution of fluorescently labeled molecules in real time in these tissues. Imaging, in general, is a rapidly developing discipline, and recent advances in imaging technology are able to greatly extend what can be achieved with live cell imaging of Drosophila tissues. As far as possible, this article includes the latest technical developments and discusses likely future developments in imaging methods that could have an impact on research using Drosophila. PMID:20360379

  18. Volatile pheromone signalling in Drosophila.

    PubMed

    Smith, Dean P

    2012-03-01

    Once captured by the antenna, 11-cis vaccenyl acetate (cVA) binds to an extracellular binding protein called LUSH that undergoes a conformational shift upon cVA binding. The stable LUSH-cVA complex is the activating ligand for pheromone receptors present on the dendrites of the aT1 neurones, comprising the only neurones that detect cVA pheromone. This mechanism explains the single molecule sensitivity of insect pheromone detection systems. The receptor that recognizes activated LUSH consists of a complex of several proteins, including Or67d, a member of the tuning odourant receptor family, Orco, a co-receptor ion channel, and SNMP, a CD36 homologue that may be an inhibitory subunit. In addition, genetic screens and reconstitution experiments reveal additional factors that are important for pheromone detection. Identification and functional dissection of these factors in Drosophila melanogaster Meigen should permit the identification of homologous factors in pathogenic insects and agricultural pests, which, in turn, may be viable candidates for novel classes of compounds to control populations of target insect species without impacting beneficial species. PMID:24347807

  19. Evaluation of Traditional Medicines for Neurodegenerative Diseases Using Drosophila Models

    PubMed Central

    Lee, Soojin; Bang, Se Min; Lee, Joon Woo; Cho, Kyoung Sang

    2014-01-01

    Drosophila is one of the oldest and most powerful genetic models and has led to novel insights into a variety of biological processes. Recently, Drosophila has emerged as a model system to study human diseases, including several important neurodegenerative diseases. Because of the genomic similarity between Drosophila and humans, Drosophila neurodegenerative disease models exhibit a variety of human-disease-like phenotypes, facilitating fast and cost-effective in vivo genetic modifier screening and drug evaluation. Using these models, many disease-associated genetic factors have been identified, leading to the identification of compelling drug candidates. Recently, the safety and efficacy of traditional medicines for human diseases have been evaluated in various animal disease models. Despite the advantages of the Drosophila model, its usage in the evaluation of traditional medicines is only nascent. Here, we introduce the Drosophila model for neurodegenerative diseases and some examples demonstrating the successful application of Drosophila models in the evaluation of traditional medicines. PMID:24790636

  20. Rosa damascena decreased mortality in adult Drosophila.

    PubMed

    Jafari, Mahtab; Zarban, Asghar; Pham, Steven; Wang, Thomas

    2008-03-01

    The effects of a rose-flower extract, Rosa damascena, on the mortality rate of Drosophila melanogaster was evaluated in this study. R. damascena is a potent antioxidant that has many therapeutic uses in addition to its perfuming effects. Supplementing Drosophila with this rose extract resulted in a statistically significant decrease in mortality rate in male and female flies. Moreover, the observed anti-aging effects were not associated with common confounds of anti-aging properties, such as a decrease in fecundity or metabolic rate. PMID:18361732

  1. Neural control of aggression in Drosophila.

    PubMed

    Hoopfer, Eric D

    2016-06-01

    Like most animal species, fruit flies fight to obtain and defend resources essential to survival and reproduction. Aggressive behavior in Drosophila is genetically specified and also strongly influenced by the fly's social context, past experiences and internal states, making it an excellent framework for investigating the neural mechanisms that regulate complex social behaviors. Here, I summarize our current knowledge of the neural control of aggression in Drosophila and discuss recent advances in understanding the sensory pathways that influence the decision to fight or court, the neuromodulatory control of aggression, the neural basis by which internal states can influence both fighting and courtship, and how social experience modifies aggressive behavior. PMID:27179788

  2. The secret lives of Drosophila flies.

    PubMed

    Markow, Therese Ann

    2015-01-01

    Flies of the genus Drosophila, and particularly those of the species Drosophila melanogaster, are best known as laboratory organisms. As with all model organisms, they were domesticated for empirical studies, but they also continue to exist as wild populations. Decades of research on these flies in the laboratory have produced astounding and important insights into basic biological processes, but we have only scratched the surface of what they have to offer as research organisms. An outstanding challenge now is to build on this knowledge and explore how natural history has shaped D. melanogaster in order to advance our understanding of biology more generally. PMID:26041333

  3. Drosophila Bitter Taste(s)

    PubMed Central

    French, Alice; Ali Agha, Moutaz; Mitra, Aniruddha; Yanagawa, Aya; Sellier, Marie-Jeanne; Marion-Poll, Frédéric

    2015-01-01

    Most animals possess taste receptors neurons detecting potentially noxious compounds. In humans, the ligands which activate these neurons define a sensory space called “bitter”. By extension, this term has been used in animals and insects to define molecules which induce aversive responses. In this review, based on our observations carried out in Drosophila, we examine how bitter compounds are detected and if bitter-sensitive neurons respond only to molecules bitter to humans. Like most animals, flies detect bitter chemicals through a specific population of taste neurons, distinct from those responding to sugars or to other modalities. Activating bitter-sensitive taste neurons induces aversive reactions and inhibits feeding. Bitter molecules also contribute to the suppression of sugar-neuron responses and can lead to a complete inhibition of the responses to sugar at the periphery. Since some bitter molecules activate bitter-sensitive neurons and some inhibit sugar detection, bitter molecules are represented by two sensory spaces which are only partially congruent. In addition to molecules which impact feeding, we recently discovered that the activation of bitter-sensitive neurons also induces grooming. Bitter-sensitive neurons of the wings and of the legs can sense chemicals from the gram negative bacteria, Escherichia coli, thus adding another biological function to these receptors. Bitter-sensitive neurons of the proboscis also respond to the inhibitory pheromone, 7-tricosene. Activating these neurons by bitter molecules in the context of sexual encounter inhibits courting and sexual reproduction, while activating these neurons with 7-tricosene in a feeding context will inhibit feeding. The picture that emerges from these observations is that the taste system is composed of detectors which monitor different “categories” of ligands, which facilitate or inhibit behaviors depending on the context (feeding, sexual reproduction, hygienic behavior), thus

  4. Open-Ended Laboratory Investigations with Drosophila.

    ERIC Educational Resources Information Center

    Mertens, Thomas R.

    1983-01-01

    Background information, laboratory procedures (including matings performed), and results are presented for an open-ended investigation using the fruitfly Drosophila melanogaster. Once data are collected, students develop hypotheses to explain results as well as devise additional experiments to test their hypotheses. Calculation of chi-square for…

  5. Measurement of Cytoplasmic Streaming in Drosophila Melanogaster

    NASA Astrophysics Data System (ADS)

    Ganguly, Sujoy; Williams, Lucy; Palacios, Isabel; Goldstein, Raymond

    2010-11-01

    During stage 9 of Drosophila melanogastor oogenesis flow of the oocyte cytoplasm, driven by kinesin 1 motor protein is observed. This cytoplasmic streaming is analyzed by PIV in both wild type and kinesin light chain mutants, revealing striking statistical differences. Further measurements of the rheology of the oocyte allow for estimations of the mechanical energy needed to generate the observed flows.

  6. Analysis of Phagocytosis in the Drosophila Ovary.

    PubMed

    Meehan, Tracy L; Serizier, Sandy B; Kleinsorge, Sarah E; McCall, Kimberly

    2016-01-01

    Programmed cell death (PCD) is essential for health and development. Generally, the last step of PCD is clearance, or engulfment, by phagocytes. Engulfment can be broken down into five basic steps: attraction of the phagocyte, recognition of the dying cell, internalization, phagosome maturation, and acidification of the engulfed material. The Drosophila melanogaster ovary serves as an excellent model to study diverse types of PCD and engulfment by epithelial cells. Here, we describe several methods to detect and analyze multiple steps of engulfment in the Drosophila ovary: recognition, vesicle uptake, phagosome maturation, and acidification. Annexin V detects phosphatidylserine, which is flipped to the outer leaflet of the plasma membrane of apoptotic cells, serving as an "eat me" signal. Several germline markers including tral-GFP, Orb, and cleaved Dcp-1 can all be used to label the germline and visualize its uptake into engulfing follicle cells. Drosophila strains expressing GFP and mCherry protein fusions can enable a detailed analysis of phagosome maturation. LysoTracker labels highly acidified compartments, marking phagolysosomes. Together these labels can be used to mark the progression of engulfment in Drosophila follicle cells. PMID:27557574

  7. The 5S genes of Drosophila melanogaster.

    PubMed

    Artavanis-Tsakonas, S; Schedl, P; Tschudi, C; Pirrotta, V; Steward, R; Gehring, W J

    1977-12-01

    We have cloned embryonic Drosophila DNA using the poly (dA-DT) connector method (Lobban and Kaiser, 1973) and the ampicillin-resistant plasmid pSF2124 (So, Gill and Falkow, 1975) as a cloning vehicle. Two clones, containing hybrid plasmids with sequences complementary to a 5S RNA probe isolated from Drosophila tissue culture cells, were identified by the Grunstein and Hogness (1975) colony hybridization procedure. One hybrid plasmid has a Drosophila insert which is comprised solely of tandem repeats of the 5S gene plus spacer sequences. The other plasmid contains an insert which has about 20 tandem 5S repeat units plus an additional 4 kilobases of adjacent sequences. The size of the 5S repeat unit was determined by gel electrophoresis and was found to be approximately 375 base pairs. We present a restriction map of both plasmids, and a detailed map of of the5S repeat unit. The 5S repat unit shows slight length and sequence heterogeneity. We present evidence suggesting that the 5S genes in Drosophila melanogaster may be arranged in a single continuous cluster. PMID:413625

  8. Organization of descending neurons in Drosophila melanogaster.

    PubMed

    Hsu, Cynthia T; Bhandawat, Vikas

    2016-01-01

    Neural processing in the brain controls behavior through descending neurons (DNs) - neurons which carry signals from the brain to the spinal cord (or thoracic ganglia in insects). Because DNs arise from multiple circuits in the brain, the numerical simplicity and availability of genetic tools make Drosophila a tractable model for understanding descending motor control. As a first step towards a comprehensive study of descending motor control, here we estimate the number and distribution of DNs in the Drosophila brain. We labeled DNs by backfilling them with dextran dye applied to the neck connective and estimated that there are ~1100 DNs distributed in 6 clusters in Drosophila. To assess the distribution of DNs by neurotransmitters, we labeled DNs in flies in which neurons expressing the major neurotransmitters were also labeled. We found DNs belonging to every neurotransmitter class we tested: acetylcholine, GABA, glutamate, serotonin, dopamine and octopamine. Both the major excitatory neurotransmitter (acetylcholine) and the major inhibitory neurotransmitter (GABA) are employed equally; this stands in contrast to vertebrate DNs which are predominantly excitatory. By comparing the distribution of DNs in Drosophila to those reported previously in other insects, we conclude that the organization of DNs in insects is highly conserved. PMID:26837716

  9. Drosophila Melanogaster as an Experimental Organism.

    ERIC Educational Resources Information Center

    Rubin, Gerald M.

    1988-01-01

    Discusses the role of the fruit fly in genetics research requiring a multidisciplinary approach. Describes embryological and genetic methods used in the experimental analysis of this organism. Outlines the use of Drosophila in the study of the development and function of the nervous system. (RT)

  10. Functional Neuroanatomy of "Drosophila" Olfactory Memory Formation

    ERIC Educational Resources Information Center

    Guven-Ozkan, Tugba; Davis, Ronald L.

    2014-01-01

    New approaches, techniques and tools invented over the last decade and a half have revolutionized the functional dissection of neural circuitry underlying "Drosophila" learning. The new methodologies have been used aggressively by researchers attempting to answer three critical questions about olfactory memories formed with appetitive…

  11. Second-Order Conditioning in "Drosophila"

    ERIC Educational Resources Information Center

    Tabone, Christopher J.; de Belle, J. Steven

    2011-01-01

    Associative conditioning in "Drosophila melanogaster" has been well documented for several decades. However, most studies report only simple associations of conditioned stimuli (CS, e.g., odor) with unconditioned stimuli (US, e.g., electric shock) to measure learning or establish memory. Here we describe a straightforward second-order conditioning…

  12. Characterization of novel microsatellites from Drosophila transversa.

    PubMed

    Räisänen, L; Roininen, E; Liimatainen, J O

    2009-03-01

    We investigated a partial genomic library of Drosophila transversa for microsatellites and developed 12 markers for genetic analyses. This is the first time that microsatellite primers from the quinaria species group have been described. Four loci were cross-amplified in D. phalerata. Nine out of the 12 microsatellite markers developed are likely to be on the X chromosome. PMID:21564716

  13. [Recombination in Drosophila in space flight].

    PubMed

    Filatova, L P; Vaulina, E N; Lapteva, N Sh; Grozdova, T Ia

    1988-04-01

    An experiment with Drosophila melanogaster males was performed aboard the Artificial Satellite "Kosmos-1667". Mutagenic effects of a 7-day space flight on intergene recombination in chromosome 2 were studied. The space flight factors decreased the frequency of recombination. A model experiment on a laboratory centrifuge demonstrated insignificant increase in recombination frequency caused by acceleration. PMID:3135244

  14. Organization of descending neurons in Drosophila melanogaster

    PubMed Central

    Hsu, Cynthia T.; Bhandawat, Vikas

    2016-01-01

    Neural processing in the brain controls behavior through descending neurons (DNs) - neurons which carry signals from the brain to the spinal cord (or thoracic ganglia in insects). Because DNs arise from multiple circuits in the brain, the numerical simplicity and availability of genetic tools make Drosophila a tractable model for understanding descending motor control. As a first step towards a comprehensive study of descending motor control, here we estimate the number and distribution of DNs in the Drosophila brain. We labeled DNs by backfilling them with dextran dye applied to the neck connective and estimated that there are ~1100 DNs distributed in 6 clusters in Drosophila. To assess the distribution of DNs by neurotransmitters, we labeled DNs in flies in which neurons expressing the major neurotransmitters were also labeled. We found DNs belonging to every neurotransmitter class we tested: acetylcholine, GABA, glutamate, serotonin, dopamine and octopamine. Both the major excitatory neurotransmitter (acetylcholine) and the major inhibitory neurotransmitter (GABA) are employed equally; this stands in contrast to vertebrate DNs which are predominantly excitatory. By comparing the distribution of DNs in Drosophila to those reported previously in other insects, we conclude that the organization of DNs in insects is highly conserved. PMID:26837716

  15. A Drosophila Model of Epidermolysis Bullosa Simplex.

    PubMed

    Bohnekamp, Jens; Cryderman, Diane E; Paululat, Achim; Baccam, Gabriel C; Wallrath, Lori L; Magin, Thomas M

    2015-08-01

    The blistering skin disorder epidermolysis bullosa simplex (EBS) results from dominant mutations in keratin 5 (K5) or keratin 14 (K14) genes, encoding the intermediate filament (IF) network of basal epidermal keratinocytes. The mechanisms governing keratin network formation and collapse due to EBS mutations remain incompletely understood. Drosophila lacks cytoplasmic IFs, providing a 'null' environment to examine the formation of keratin networks and determine mechanisms by which mutant keratins cause pathology. Here, we report that ubiquitous co-expression of transgenes encoding wild-type human K14 and K5 resulted in the formation of extensive keratin networks in Drosophila epithelial and non-epithelial tissues, causing no overt phenotype. Similar to mammalian cells, treatment of transgenic fly tissues with phosphatase inhibitors caused keratin network collapse, validating Drosophila as a genetic model system to investigate keratin dynamics. Co-expression of K5 and a K14(R125C) mutant that causes the most severe form of EBS resulted in widespread formation of EBS-like cytoplasmic keratin aggregates in epithelial and non-epithelial fly tissues. Expression of K14(R125C)/K5 caused semi-lethality; adult survivors developed wing blisters and were flightless due to a lack of intercellular adhesion during wing heart development. This Drosophila model of EBS is valuable for the identification of pathways altered by mutant keratins and for the development of EBS therapies. PMID:25830653

  16. Genomics of Ecological Adaptation in Cactophilic Drosophila

    PubMed Central

    Guillén, Yolanda; Rius, Núria; Delprat, Alejandra; Williford, Anna; Muyas, Francesc; Puig, Marta; Casillas, Sònia; Ràmia, Miquel; Egea, Raquel; Negre, Barbara; Mir, Gisela; Camps, Jordi; Moncunill, Valentí; Ruiz-Ruano, Francisco J.; Cabrero, Josefa; de Lima, Leonardo G.; Dias, Guilherme B.; Ruiz, Jeronimo C.; Kapusta, Aurélie; Garcia-Mas, Jordi; Gut, Marta; Gut, Ivo G.; Torrents, David; Camacho, Juan P.; Kuhn, Gustavo C.S.; Feschotte, Cédric; Clark, Andrew G.; Betrán, Esther; Barbadilla, Antonio; Ruiz, Alfredo

    2015-01-01

    Cactophilic Drosophila species provide a valuable model to study gene–environment interactions and ecological adaptation. Drosophila buzzatii and Drosophila mojavensis are two cactophilic species that belong to the repleta group, but have very different geographical distributions and primary host plants. To investigate the genomic basis of ecological adaptation, we sequenced the genome and developmental transcriptome of D. buzzatii and compared its gene content with that of D. mojavensis and two other noncactophilic Drosophila species in the same subgenus. The newly sequenced D. buzzatii genome (161.5 Mb) comprises 826 scaffolds (>3 kb) and contains 13,657 annotated protein-coding genes. Using RNA sequencing data of five life-stages we found expression of 15,026 genes, 80% protein-coding genes, and 20% noncoding RNA genes. In total, we detected 1,294 genes putatively under positive selection. Interestingly, among genes under positive selection in the D. mojavensis lineage, there is an excess of genes involved in metabolism of heterocyclic compounds that are abundant in Stenocereus cacti and toxic to nonresident Drosophila species. We found 117 orphan genes in the shared D. buzzatii–D. mojavensis lineage. In addition, gene duplication analysis identified lineage-specific expanded families with functional annotations associated with proteolysis, zinc ion binding, chitin binding, sensory perception, ethanol tolerance, immunity, physiology, and reproduction. In summary, we identified genetic signatures of adaptation in the shared D. buzzatii–D. mojavensis lineage, and in the two separate D. buzzatii and D. mojavensis lineages. Many of the novel lineage-specific genomic features are promising candidates for explaining the adaptation of these species to their distinct ecological niches. PMID:25552534

  17. Optogenetic pacing in Drosophila melanogaster (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Alex, Aneesh; Li, Airong; Men, Jing; Jerwick, Jason; Tanzi, Rudolph E.; Zhou, Chao

    2016-03-01

    A non-invasive, contact-less cardiac pacing technology can be a powerful tool in basic cardiac research and in clinics. Currently, electrical pacing is the gold standard for cardiac pacing. Although highly effective in controlling the cardiac function, the invasive nature, non-specificity to cardiac tissues and possible tissue damage limits its capabilities. Optical pacing of heart is a promising alternative, which is non-invasive and more specific, has high spatial and temporal precision, and avoids shortcomings in electrical stimulation. Optical coherence tomography has been proved to be an effective technique in non-invasive imaging in vivo with ultrahigh resolution and imaging speed. In the last several years, non-invasive specific optical pacing in animal hearts has been reported in quail, zebrafish, and rabbit models. However, Drosophila Melanogaster, which is a significant model with orthologs of 75% of human disease genes, has rarely been studied concerning their optical pacing in heart. Here, we combined optogenetic control of Drosophila heartbeat with optical coherence microscopy (OCM) technique for the first time. The light-gated cation channel, channelrhodopsin-2 (ChR2) was specifically expressed by transgene as a pacemaker in drosophila heart. By stimulating the pacemaker with 472 nm pulsed laser light at different frequencies, we achieved non-invasive and more specific optical control of the Drosophila heart rhythm, which demonstrates the wide potential of optical pacing for studying cardiac dynamics and development. Imaging capability of our customized OCM system was also involved to observe the pacing effect visually. No tissue damage was found after long exposure to laser pulses, which proved the safety of optogenetic control of Drosophila heart.

  18. Organization and Evolution of Drosophila Terminin: Similarities and Differences between Drosophila and Human Telomeres.

    PubMed

    Raffa, Grazia D; Cenci, Giovanni; Ciapponi, Laura; Gatti, Maurizio

    2013-01-01

    Drosophila lacks telomerase and fly telomeres are elongated by occasional transposition of three specialized retroelements. Drosophila telomeres do not terminate with GC-rich repeats and are assembled independently of the sequence of chromosome ends. Recent work has shown that Drosophila telomeres are capped by the terminin complex, which includes the fast-evolving proteins HOAP, HipHop, Moi, and Ver. These proteins, which are not conserved outside Drosophilidae and closely related Diptera, localize and function exclusively at telomeres, protecting them from fusion events. Other proteins required to prevent end-to-end fusion in flies include HP1, Eff/UbcD1, ATM, the components of the Mre11-Rad50-Nbs (MRN) complex, and the Woc transcription factor. These proteins do not share the terminin properties; they are evolutionarily conserved non-fast-evolving proteins that do not accumulate only at telomeres and do not serve telomere-specific functions. We propose that following telomerase loss, Drosophila rapidly evolved terminin to bind chromosome ends in a sequence-independent manner. This hypothesis suggests that terminin is the functional analog of the shelterin complex that protects human telomeres. The non-terminin proteins are instead likely to correspond to ancestral telomere-associated proteins that did not evolve as rapidly as terminin because of the functional constraints imposed by their involvement in diverse cellular processes. Thus, it appears that the main difference between Drosophila and human telomeres is in the protective complexes that specifically associate with the DNA termini. We believe that Drosophila telomeres offer excellent opportunities for investigations on human telomere biology. The identification of additional Drosophila genes encoding non-terminin proteins involved in telomere protection might lead to the discovery of novel components of human telomeres. PMID:23675571

  19. Organization and Evolution of Drosophila Terminin: Similarities and Differences between Drosophila and Human Telomeres

    PubMed Central

    Raffa, Grazia D.; Cenci, Giovanni; Ciapponi, Laura; Gatti, Maurizio

    2013-01-01

    Drosophila lacks telomerase and fly telomeres are elongated by occasional transposition of three specialized retroelements. Drosophila telomeres do not terminate with GC-rich repeats and are assembled independently of the sequence of chromosome ends. Recent work has shown that Drosophila telomeres are capped by the terminin complex, which includes the fast-evolving proteins HOAP, HipHop, Moi, and Ver. These proteins, which are not conserved outside Drosophilidae and closely related Diptera, localize and function exclusively at telomeres, protecting them from fusion events. Other proteins required to prevent end-to-end fusion in flies include HP1, Eff/UbcD1, ATM, the components of the Mre11-Rad50-Nbs (MRN) complex, and the Woc transcription factor. These proteins do not share the terminin properties; they are evolutionarily conserved non-fast-evolving proteins that do not accumulate only at telomeres and do not serve telomere-specific functions. We propose that following telomerase loss, Drosophila rapidly evolved terminin to bind chromosome ends in a sequence-independent manner. This hypothesis suggests that terminin is the functional analog of the shelterin complex that protects human telomeres. The non-terminin proteins are instead likely to correspond to ancestral telomere-associated proteins that did not evolve as rapidly as terminin because of the functional constraints imposed by their involvement in diverse cellular processes. Thus, it appears that the main difference between Drosophila and human telomeres is in the protective complexes that specifically associate with the DNA termini. We believe that Drosophila telomeres offer excellent opportunities for investigations on human telomere biology. The identification of additional Drosophila genes encoding non-terminin proteins involved in telomere protection might lead to the discovery of novel components of human telomeres. PMID:23675571

  20. The first complete Mag family retrotransposons discovered in Drosophila.

    PubMed

    Glukhov, I A; Kotnova, A P; Stefanov, Y E; Ilyin, Y V

    2016-01-01

    A retrotransposon of the Mag family was found in the Drosophila simulans genome for the first time. We also identified novel transposable elements representing the Mag family in seven Drosophila species. The high similarity between the 3' and 5' long terminal repeats in the found copies of transposable elements indicates that their retrotransposition has occurred relatively recently. Thus, the Mag family of retrotransposons is quite common for the genus Drosophila. PMID:27025475

  1. Rapamycin preserves gut homeostasis during Drosophila aging.

    PubMed

    Fan, Xiaolan; Liang, Qing; Lian, Ting; Wu, Qi; Gaur, Uma; Li, Diyan; Yang, Deying; Mao, Xueping; Jin, Zhihua; Li, Ying; Yang, Mingyao

    2015-11-01

    Gut homeostasis plays an important role in maintaining the overall body health during aging. Rapamycin, a specific inhibitor of mTOR, exerts prolongevity effects in evolutionarily diverse species. However, its impact on the intestinal homeostasis remains poorly understood. Here, we demonstrate that rapamycin can slow down the proliferation rate of intestinal stem cells (ISCs) in the aging guts and induce autophagy in the intestinal epithelium in Drosophila. Rapamycin can also significantly affect the FOXO associated genes in intestine and up-regulate the negative regulators of IMD/Rel pathway, consequently delaying the microbial expansion in the aging guts. Collectively, these findings reveal that rapamycin can delay the intestinal aging by inhibiting mTOR and thus keeping stem cell proliferation in check. These results will further explain the mechanism of healthspan and lifespan extension by rapamycin in Drosophila. PMID:26431326

  2. Quantifying and predicting Drosophila larvae crawling phenotypes

    PubMed Central

    Günther, Maximilian N.; Nettesheim, Guilherme; Shubeita, George T.

    2016-01-01

    The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly’s power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer’s disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design. PMID:27323901

  3. Towards a Molecular Understanding of Drosophila Hearing

    PubMed Central

    Caldwell, Jason C.; Eberl, Daniel F.

    2007-01-01

    The Drosophila auditory system is presented as a powerful new genetic model system for understanding the molecular aspects of development and physiology of hearing organs. The fly’s ear resides in the antenna, with Johnston’s organ serving as the mechanoreceptor. New approaches using electrophysiology and laser vibrometry have provided useful tools to apply to the study of mutations that disrupt hearing. The fundamental developmental processes that generate the peripheral nervous system are fairly well understood, although specific variations of these processes for chordotonal organs (CHO) and especially for Johnston’s organ require more scrutiny. In contrast, even the fundamental physiologic workings of mechanosensitive systems are still poorly understood, but rapid recent progress is beginning to shed light. The identification and analysis of mutations that affect auditory function are summarized here, and prospects for the role of the Drosophila auditory system in understanding both insect and vertebrate hearing are discussed. PMID:12382274

  4. Counting calories in Drosophila diet restriction.

    PubMed

    Min, Kyung-Jin; Flatt, Thomas; Kulaots, Indrek; Tatar, Marc

    2007-03-01

    The extension of life span by diet restriction in Drosophila has been argued to occur without limiting calories. Here we directly measure the calories assimilated by flies when maintained on full- and restricted-diets. We find that caloric intake is reduced on all diets that extend life span. Flies on low-yeast diet are long-lived and consume about half the calories of flies on high-yeast diets, regardless of the energetic content of the diet itself. Since caloric intake correlates with yeast concentration and thus with the intake of every metabolite in this dietary component, it is premature to conclude for Drosophila that calories do not explain extension of life span. PMID:17125951

  5. The genome sequence of Drosophila melanogaster.

    SciTech Connect

    2000-03-24

    The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the {approximately}120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes {approximately}13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

  6. Quantifying and predicting Drosophila larvae crawling phenotypes.

    PubMed

    Günther, Maximilian N; Nettesheim, Guilherme; Shubeita, George T

    2016-01-01

    The fruit fly Drosophila melanogaster is a widely used model for cell biology, development, disease, and neuroscience. The fly's power as a genetic model for disease and neuroscience can be augmented by a quantitative description of its behavior. Here we show that we can accurately account for the complex and unique crawling patterns exhibited by individual Drosophila larvae using a small set of four parameters obtained from the trajectories of a few crawling larvae. The values of these parameters change for larvae from different genetic mutants, as we demonstrate for fly models of Alzheimer's disease and the Fragile X syndrome, allowing applications such as genetic or drug screens. Using the quantitative model of larval crawling developed here we use the mutant-specific parameters to robustly simulate larval crawling, which allows estimating the feasibility of laborious experimental assays and aids in their design. PMID:27323901

  7. [The comeback of mitochondria in Drosophila apoptosis].

    PubMed

    Clavier, Amandine; Rincheval-Arnold, Aurore; Mignotte, Bernard; Guénal, Isabelle

    2016-05-01

    The role of the mitochondrion in mammalian cell apoptosis has been established since the mid-1990s. However, the importance of this organelle in non-mammalian apoptosis has long been regarded as minor, notably because of the absence of a crucial role for cytochrome c in caspase activation. Recent results indicate that the control of caspase activation and apoptosis in Drosophila cell death occurs at the mitochondrial level. Numerous proteins that appear key for Drosophila apoptosis regulation constitutively or transiently bind to mitochondria. They participate in the cell death process at different levels such as degradation of an IAP caspase inhibitor, production of mitochondrial reactive oxygen species or stimulation of the mitochondrial fission machinery. The aim of this review is to take stock of these events that might have their counterpart in humans. PMID:27225920

  8. Vertebrate eye development as modeled in Drosophila.

    PubMed

    Wawersik, S; Maas, R L

    2000-04-12

    Pax6, a member of the paired-box family of transcription factors, is critical for oculogenesis in both vertebrates and insects. Identification of potential vertebrate Pax6 targets has been guided by studies in Drosophila, where the Pax6 homologs eyeless ( ey ) and twin of eyeless ( toy ) function within a network of genes that synergistically pattern the developing fly eye. These targets, which share homology with the fly genes sine oculis, eyes absent and dachshund, exist in mice and humans as the Six, Eya and Dach gene families. Members of these gene families are present in the developing vertebrate eye, and preliminary studies suggest that they may function in a network analogous to that in the fly. Thus, despite radically different architecture, a similar molecular scaffold underlies both vertebrate and fly eye patterning, suggesting that the considerable power of Drosophila genetics can be harnessed to study mammalian ocular development. PMID:10767315

  9. Remembering Components of Food in Drosophila

    PubMed Central

    Das, Gaurav; Lin, Suewei; Waddell, Scott

    2016-01-01

    Remembering features of past feeding experience can refine foraging and food choice. Insects can learn to associate sensory cues with components of food, such as sugars, amino acids, water, salt, alcohol, toxins and pathogens. In the fruit fly Drosophila some food components activate unique subsets of dopaminergic neurons (DANs) that innervate distinct functional zones on the mushroom bodies (MBs). This architecture suggests that the overall dopaminergic neuron population could provide a potential cellular substrate through which the fly might learn to value a variety of food components. In addition, such an arrangement predicts that individual component memories reside in unique locations. DANs are also critical for food memory consolidation and deprivation-state dependent motivational control of the expression of food-relevant memories. Here, we review our current knowledge of how nutrient-specific memories are formed, consolidated and specifically retrieved in insects, with a particular emphasis on Drosophila. PMID:26924969

  10. The secret lives of Drosophila flies

    PubMed Central

    Markow, Therese Ann

    2015-01-01

    Abstract Flies of the genus Drosophila, and particularly those of the species Drosophila melanogaster, are best known as laboratory organisms. As with all model organisms, they were domesticated for empirical studies, but they also continue to exist as wild populations. Decades of research on these flies in the laboratory have produced astounding and important insights into basic biological processes, but we have only scratched the surface of what they have to offer as research organisms. An outstanding challenge now is to build on this knowledge and explore how natural history has shaped D. melanogaster in order to advance our understanding of biology more generally. DOI: http://dx.doi.org/10.7554/eLife.06793.001 PMID:26041333

  11. Maintenance of a Drosophila melanogaster Population Cage

    PubMed Central

    Caravaca, Juan Manuel; Lei, Elissa P.

    2016-01-01

    Large quantities of DNA, RNA, proteins and other cellular components are often required for biochemistry and molecular biology experiments. The short life cycle of Drosophila enables collection of large quantities of material from embryos, larvae, pupae and adult flies, in a synchronized way, at a low economic cost. A major strategy for propagating large numbers of flies is the use of a fly population cage. This useful and common tool in the Drososphila community is an efficient way to regularly produce milligrams to tens of grams of embryos, depending on uniformity of developmental stage desired. While a population cage can be time consuming to set up, maintaining a cage over months takes much less time and enables rapid collection of biological material in a short period. This paper describes a detailed and flexible protocol for the maintenance of a Drosophila melanogaster population cage, starting with 1.5 g of harvested material from the previous cycle. PMID:27023790

  12. Rapamycin preserves gut homeostasis during Drosophila aging

    PubMed Central

    Lian, Ting; Wu, Qi; Gaur, Uma; Li, Diyan; Yang, Deying; Mao, Xueping; Jin, Zhihua; Li, Ying; Yang, Mingyao

    2015-01-01

    Gut homeostasis plays an important role in maintaining the overall body health during aging. Rapamycin, a specific inhibitor of mTOR, exerts prolongevity effects in evolutionarily diverse species. However, its impact on the intestinal homeostasis remains poorly understood. Here, we demonstrate that rapamycin can slow down the proliferation rate of intestinal stem cells (ISCs) in the aging guts and induce autophagy in the intestinal epithelium in Drosophila. Rapamycin can also significantly affect the FOXO associated genes in intestine and up-regulate the negative regulators of IMD/Rel pathway, consequently delaying the microbial expansion in the aging guts. Collectively, these findings reveal that rapamycin can delay the intestinal aging by inhibiting mTOR and thus keeping stem cell proliferation in check. These results will further explain the mechanism of healthspan and lifespan extension by rapamycin in Drosophila. PMID:26431326

  13. Imaging Calcium in Drosophila at Egg Activation.

    PubMed

    Derrick, Christopher J; York-Andersen, Anna H; Weil, Timothy T

    2016-01-01

    Egg activation is a universal process that includes a series of events to allow the fertilized egg to complete meiosis and initiate embryonic development. One aspect of egg activation, conserved across all organisms examined, is a change in the intracellular concentration of calcium (Ca(2+)) often termed a 'Ca(2+) wave'. While the speed and number of oscillations of the Ca(2+) wave varies between species, the change in intracellular Ca(2+) is key in bringing about essential events for embryonic development. These changes include resumption of the cell cycle, mRNA regulation, cortical granule exocytosis, and rearrangement of the cytoskeleton. In the mature Drosophila egg, activation occurs in the female oviduct prior to fertilization, initiating a series of Ca(2+)-dependent events. Here we present a protocol for imaging the Ca(2+) wave in Drosophila. This approach provides a manipulable model system to interrogate the mechanism of the Ca(2+) wave and the downstream changes associated with it. PMID:27584955

  14. Flightless Flies: Drosophila models of neuromuscular disease

    PubMed Central

    Lloyd, Thomas E.; Taylor, J. Paul

    2010-01-01

    The fruit fly, Drosophila melanogaster, has a long and rich history as an important model organism for biologists. In particular, study of the fruit fly has been essential to much of our fundamental understanding of the development and function of the nervous system. In recent years, studies using fruit flies have provided important insights into the pathogenesis of neurodegenerative and neuromuscular diseases. Fly models of spinal muscular atrophy, spinobulbar muscular atrophy, myotonic dystrophy, dystrophinopathies and other inherited neuromuscular diseases recapitulate many of the key pathologic features of the human disease. The ability to perform genetic screens holds promise for uncovering the molecular mechanisms of disease, and indeed, for identifying novel therapeutic targets. This review will summarize recent progress in developing fly models of neuromuscular diseases and will emphasize the contribution that Drosophila has made to our understanding of these diseases. PMID:20329357

  15. Three-Dimensional Imaging of Drosophila melanogaster

    PubMed Central

    McGurk, Leeanne; Morrison, Harris; Keegan, Liam P.; Sharpe, James; O'Connell, Mary A.

    2007-01-01

    Background The major hindrance to imaging the intact adult Drosophila is that the dark exoskeleton makes it impossible to image through the cuticle. We have overcome this obstacle and describe a method whereby the internal organs of adult Drosophila can be imaged in 3D by bleaching and clearing the adult and then imaging using a technique called optical projection tomography (OPT). The data is displayed as 2D optical sections and also in 3D to provide detail on the shape and structure of the adult anatomy. Methodology We have used OPT to visualize in 2D and 3D the detailed internal anatomy of the intact adult Drosophila. In addition this clearing method used for OPT was tested for imaging with confocal microscopy. Using OPT we have visualized the size and shape of neurodegenerative vacuoles from within the head capsule of flies that suffer from age-related neurodegeneration due to a lack of ADAR mediated RNA-editing. In addition we have visualized tau-lacZ expression in 2D and 3D. This shows that the wholemount adult can be stained without any manipulation and that this stain penetrates well as we have mapped the localization pattern with respect to the internal anatomy. Conclusion We show for the first time that the intact adult Drosophila can be imaged in 3D using OPT, also we show that this method of clearing is also suitable for confocal microscopy to image the brain from within the intact head. The major advantage of this is that organs can be represented in 3D in their natural surroundings. Furthermore optical sections are generated in each of the three planes and are not prone to the technical limitations that are associated with manual sectioning. OPT can be used to dissect mutant phenotypes and to globally map gene expression in both 2D and 3D. PMID:17786206

  16. A Drosophila model to image phagosome maturation.

    PubMed

    Shandala, Tetyana; Lim, Chiaoxin; Sorvina, Alexandra; Brooks, Douglas A

    2013-01-01

    Phagocytosis involves the internalization of extracellular material by invagination of the plasma membrane to form intracellular vesicles called phagosomes, which have functions that include pathogen degradation. The degradative properties of phagosomes are thought to be conferred by sequential fusion with endosomes and lysosomes; however, this maturation process has not been studied in vivo. We employed Drosophila hemocytes, which are similar to mammalian professional macrophages, to establish a model of phagosome maturation. Adult Drosophila females, carrying transgenic Rab7-GFP endosome and Lamp1-GFP lysosome markers, were injected with E. coli DH5α and the hemocytes were collected at 15, 30, 45 and 60 minutes after infection. In wild-type females, E. coli were detected within enlarged Rab7-GFP positive phagosomes at 15 to 45 minutes after infection; and were also observed in enlarged Lamp1-GFP positive phagolysosomes at 45 minutes. Two-photon imaging of hemocytes in vivo confirmed this vesicle morphology, including enlargement of Rab7-GFP and Lamp1-GFP structures that often appeared to protrude from hemocytes. The interaction of endosomes and lysosomes with E. coli phagosomes observed in Drosophila hemocytes was consistent with that previously described for phagosome maturation in human ex vivo macrophages. We also tested our model as a tool for genetic analysis using 14-3-3e mutants, and demonstrated altered phagosome maturation with delayed E. coli internalization, trafficking and/or degradation. These findings demonstrate that Drosophila hemocytes provide an appropriate, genetically amenable, model for analyzing phagosome maturation ex vivo and in vivo. PMID:24709696

  17. Psychomotor Behavior: A Practical Approach in Drosophila

    PubMed Central

    Iliadi, Konstantin G.; Gluscencova, Oxana B.; Boulianne, Gabrielle L.

    2016-01-01

    Psychomotor behaviors are governed by fine relationships between physical activity and cognitive functions. Disturbances in psychomotor development and performance are a hallmark of many mental illnesses and often appear as observable and measurable behaviors. Here, we describe a new method called an “equilibrist test,” which can be used to quantify psychomotor learning and performance in Drosophila. We also show how this test can be used to quantify motor disturbances at relatively early stages in the development of neurodegenerative diseases.

  18. Detection of Cell Death in Drosophila Tissues

    PubMed Central

    Vasudevan, Deepika; Ryoo, Hyung Don

    2016-01-01

    Drosophila has served as a particularly attractive model to study cell death due to the vast array of tools for genetic manipulation under defined spatial and temporal conditions in vivo as well as in cultured cells. These genetic methods have been well supplemented by enzymatic assays and a panel of antibodies recognizing cell death markers. This chapter discusses reporters, mutants and assays used by various laboratories to study cell death in the context of development and in response to external insults. PMID:27108437

  19. The development of the Drosophila larval brain.

    PubMed

    Hartenstein, Volker; Spindler, Shana; Pereanu, Wayne; Fung, Siaumin

    2008-01-01

    In this chapter we will start out by describing in more detail the progenitors of the nervous system, the neuroblasts and ganglion mother cells. Subsequently we will survey the generic cell types that make up the developing Drosophila brain, namely neurons, glial cells and tracheal cells. Finally, we will attempt a synopsis of the neuronal connectivity of the larval brain that can be deduced from the analysis of neural lineages and their relationship to neuropile compartments. PMID:18683635

  20. Queuine metabolism and cadmium toxicity in Drosophila

    SciTech Connect

    Farkas, W.R.; Siard, T. ); Jacobson, K.B. )

    1991-03-11

    Queuine is a derivative of guanine found in the first position of the anticodon of the transfer RNAs for Asp, Asn, His and Tyr. The transcripts of these tRNAs contain a guanine in this position. This guanine is enzymatically excised and replaced by queuine. The ratio of queuine-containing or (q+) tRNA to its precursor or (q{minus}) tRNA changes throughout the Drosophila life cycle. in the egg 10% of the tRNA is (q+). During the three larval stages this ratio drops to zero. In the one day old adult it is about 10%. It has previously been shown that when flies are selected for the ability to grow in the presence of cadmium, the tolerant flies had 100% (q+) tRNA at the first day after pupation instead of 10%. However, it was not known whether the elevated level of (q+) tRNA was a coincidence or if the elevated levels of (q+) tRNA was protective. The authors explored this problem using germfree Drosophila. The first thing was to determine if Drosophila can synthesize queuine. Sterilized eggs were seeded onto sterile chemically defined medium. The flies were grown to the adult stage. This study showed that Drosophila like mammals cannot synthesize queuine. A second result of this research was the demonstration that the authors could alter the ratio of (q+) to (q{minus}) tRNA by adding exogenous queuine to the medium e.g. at 0.008 mM queuine the (q+) tRNA was 95% instead of {lt} 5% in the last instar stage. Finally, the authors investigated whether or not queuine gave protection against cadmium. The results were that when the flies were grown in the presence of 0.2 mM cadmium queuine at 0.008 mM gave a statistically significant increase in the number of survivors.

  1. Dimethylnitrosamine demethylase activity in Drosophila melanogaster

    SciTech Connect

    Waters, L.C.; Nix, C.E.; Epler, J.L.

    1982-06-15

    A dimethylnitrosamine (DMN) demethylase with levels of activity comparable to that in uninduced rat liver was demonstrated in both larval and adult forms of the Hikone-R strain of Drosophila. A microsomal enzyme, it has many properties of a cytochrome P-450-containing mixed-function oxidase. Kinetic analysis indicates only a single enzyme with an apparent K/sub m/ of 10.5 mM DMN.

  2. ‘Peer pressure’ in larval Drosophila?

    PubMed Central

    Niewalda, Thomas; Jeske, Ines; Michels, Birgit; Gerber, Bertram

    2014-01-01

    ABSTRACT Understanding social behaviour requires a study case that is simple enough to be tractable, yet complex enough to remain interesting. Do larval Drosophila meet these requirements? In a broad sense, this question can refer to effects of the mere presence of other larvae on the behaviour of a target individual. Here we focused in a more strict sense on ‘peer pressure’, that is on the question of whether the behaviour of a target individual larva is affected by what a surrounding group of larvae is doing. We found that innate olfactory preference of a target individual was neither affected (i) by the level of innate olfactory preference in the surrounding group nor (ii) by the expression of learned olfactory preference in the group. Likewise, learned olfactory preference of a target individual was neither affected (iii) by the level of innate olfactory preference of the surrounding group nor (iv) by the learned olfactory preference the group was expressing. We conclude that larval Drosophila thus do not take note of specifically what surrounding larvae are doing. This implies that in a strict sense, and to the extent tested, there is no social interaction between larvae. These results validate widely used en mass approaches to the behaviour of larval Drosophila. PMID:24907371

  3. SPARC–Dependent Cardiomyopathy in Drosophila

    PubMed Central

    Motamedchaboki, Khatereh; Bodmer, Rolf

    2016-01-01

    Background— The Drosophila heart is an important model for studying the genetics underpinning mammalian cardiac function. The system comprises contractile cardiomyocytes, adjacent to which are pairs of highly endocytic pericardial nephrocytes that modulate cardiac function by uncharacterized mechanisms. Identifying these mechanisms and the molecules involved is important because they may be relevant to human cardiac physiology. Methods and Results— This work aimed to identify circulating cardiomodulatory factors of potential relevance to humans using the Drosophila nephrocyte–cardiomyocyte system. A Kruppel-like factor 15 (dKlf15) loss-of-function strategy was used to ablate nephrocytes and then heart function and the hemolymph proteome were analyzed. Ablation of nephrocytes led to a severe cardiomyopathy characterized by a lengthening of diastolic interval. Rendering adult nephrocytes dysfunctional by disrupting their endocytic function or temporally conditional knockdown of dKlf15 led to a similar cardiomyopathy. Proteomics revealed that nephrocytes regulate the circulating levels of many secreted proteins, the most notable of which was the evolutionarily conserved matricellular protein Secreted Protein Acidic and Rich in Cysteine (SPARC), a protein involved in mammalian cardiac function. Finally, reducing SPARC gene dosage ameliorated the cardiomyopathy that developed in the absence of nephrocytes. Conclusions— The data implicate SPARC in the noncell autonomous control of cardiac function in Drosophila and suggest that modulation of SPARC gene expression may ameliorate cardiac dysfunction in humans. PMID:26839388

  4. Flying Drosophila orient to sky polarization.

    PubMed

    Weir, Peter T; Dickinson, Michael H

    2012-01-10

    Insects maintain a constant bearing across a wide range of spatial scales. Monarch butterflies and locusts traverse continents [1, 2], and foraging bees and ants travel hundreds of meters to return to their nests [1, 3, 4], whereas many other insects fly straight for only a few centimeters before changing direction. Despite this variation in spatial scale, the brain region thought to underlie long-distance navigation is remarkably conserved [5, 6], suggesting that the use of a celestial compass is a general and perhaps ancient capability of insects. Laboratory studies of Drosophila have identified a local search mode in which short, straight segments are interspersed with rapid turns [7, 8]. However, this flight mode is inconsistent with measured gene flow between geographically separated populations [9-11], and individual Drosophila can travel 10 km across desert terrain in a single night [9, 12, 13]-a feat that would be impossible without prolonged periods of straight flight. To directly examine orientation behavior under outdoor conditions, we built a portable flight arena in which a fly viewed the natural sky through a liquid crystal device that could experimentally rotate the polarization angle. Our findings indicate that Drosophila actively orient using the sky's natural polarization pattern. PMID:22177905

  5. Calcium and egg activation in Drosophila.

    PubMed

    Sartain, Caroline V; Wolfner, Mariana F

    2013-01-01

    In many animals, a rise in intracellular calcium levels is the trigger for egg activation, the process by which an arrested mature oocyte transitions to prepare for embryogenesis. In nearly all animals studied to date, this calcium rise, and thus egg activation, is triggered by the fertilizing sperm. However in the insects that have been examined, fertilization is not necessary to activate their oocytes. Rather, these insects' eggs activate as they transit through the female's reproductive tract, regardless of male contribution. Recent studies in Drosophila have shown that egg activation nevertheless requires calcium and that the downstream events and molecules of egg activation are also conserved, despite the difference in initial trigger. Genetic studies have uncovered essential roles for the calcium-dependent enzyme calcineurin and its regulator calcipressin, and have hinted at roles for calmodulin, in Drosophila egg activation. Physiological and in vitro studies have led to a model in which mechanical forces that impact the Drosophila oocyte as it moves through the reproductive tract triggers the influx of calcium from the external environment, thereby initiating egg activation. Future research will aim to test this model, as well as to determine the spatiotemporal dynamics of cytoplasmic calcium flux and mode of signal propagation in this unique system. PMID:23218670

  6. ``sex Ratio'' Meiotic Drive in Drosophila Testacea

    PubMed Central

    James, A. C.; Jaenike, J.

    1990-01-01

    We document the occurrence of ``sex ratio'' meiotic drive in natural populations of Drosophila testacea. ``Sex ratio'' males sire >95% female offspring. Genetic analysis reveals that this effect is due to a meiotically driven X chromosome, as in other species of Drosophila in which ``sex ratio'' has been found. In contrast to other drosophilids, the ``sex ratio'' and standard chromosomes of D. testacea do not differ in gene arrangement, implying that the effect may be due to a single genetic factor in this species. In all likelihood, the ``sex ratio'' condition has evolved independently in D. testacea and in the Drosophila obscura species group, as the loci responsible for the effect occur on different chromosomal elements. An important ecological consequence of ``sex ratio'' is that natural populations of D. testacea exhibit a strong female bias. Because D. testacea mates, oviposits, and feeds as adults and larvae on mushrooms, this species provides an excellent opportunity to study the selective factors in nature that prevent ``sex ratio'' chromosomes from increasing to fixation and causing the extinction of the species. PMID:2249763

  7. Imprinted control of gene activity in Drosophila.

    PubMed

    Golic, K G; Golic, M M; Pimpinelli, S

    1998-11-19

    Genetic imprinting is defined as a reversible, differential marking of genes or chromosomes that is determined by the sex of the parent from whom the genetic material is inherited [1]. Imprinting was first observed in insects where, in some species, most notably among the coccoids (scale insects and allies), the differential marking of paternally and maternally transmitted chromosome sets leads to inactivation or elimination of paternal chromosomes [2]. Imprinting is also widespread in plants and mammals [3,4], in which paternally and maternally inherited alleles may be differentially expressed. Despite imprinting having been discovered in insects, clear examples of parental imprinting are scarce in the model insect species Drosophila melanogaster. We describe a case of imprint-mediated control of gene expression in Drosophila. The imprinted gene - the white+ eye-color gene - is expressed at a low level when transmitted by males, and at a high level when transmitted by females. Thus, in common with coccoids, Drosophila is capable of generating an imprint, and can respond to that imprint by silencing the paternal allele. PMID:9822579

  8. Visualizing the spindle checkpoint in Drosophila spermatocytes

    PubMed Central

    Rebollo, Elena; González, Cayetano

    2000-01-01

    The spindle assembly checkpoint detects defects in spindle structure or in the alignment of the chromosomes on the metaphase plate and delays the onset of anaphase until defects are corrected. Thus far, the evidence regarding the presence of a spindle checkpoint during meiosis in male Drosophila has been indirect and contradictory. On the one hand, chromosomes without pairing partners do not prevent meiosis progression. On the other hand, some conserved components of the spindle checkpoint machinery are expressed in these cells and behave as their homologue proteins do in systems with an active spindle checkpoint. To establish whether the spindle checkpoint is active in Drosophila spermatocytes we have followed meiosis progression by time-lapse microscopy under conditions where the checkpoint is likely to be activated. We have found that the presence of a relatively high number of misaligned chromosomes or a severe disruption of the meiotic spindle results in a significant delay in the time of entry into anaphase. These observations provide the first direct evidence substantiating the activity of a meiotic spindle checkpoint in male Drosophila. PMID:11256627

  9. The Ran Pathway in Drosophila melanogaster Mitosis

    PubMed Central

    Chen, Jack W. C.; Barker, Amy R.; Wakefield, James G.

    2015-01-01

    Over the last two decades, the small GTPase Ran has emerged as a central regulator of both mitosis and meiosis, particularly in the generation, maintenance, and regulation of the microtubule (MT)-based bipolar spindle. Ran-regulated pathways in mitosis bear many similarities to the well-characterized functions of Ran in nuclear transport and, as with transport, the majority of these mitotic effects are mediated through affecting the physical interaction between karyopherins and Spindle Assembly Factors (SAFs)—a loose term describing proteins or protein complexes involved in spindle assembly through promoting nucleation, stabilization, and/or depolymerization of MTs, through anchoring MTs to specific structures such as centrosomes, chromatin or kinetochores, or through sliding MTs along each other to generate the force required to achieve bipolarity. As such, the Ran-mediated pathway represents a crucial functional module within the wider spindle assembly landscape. Research into mitosis using the model organism Drosophila melanogaster has contributed substantially to our understanding of centrosome and spindle function. However, in comparison to mammalian systems, very little is known about the contribution of Ran-mediated pathways in Drosophila mitosis. This article sets out to summarize our understanding of the roles of the Ran pathway components in Drosophila mitosis, focusing on the syncytial blastoderm embryo, arguing that it can provide important insights into the conserved functions on Ran during spindle formation. PMID:26636083

  10. dachshund Potentiates Hedgehog Signaling during Drosophila Retinogenesis

    PubMed Central

    Aerts, Stein; Casares, Fernando; Janody, Florence

    2016-01-01

    Proper organ patterning depends on a tight coordination between cell proliferation and differentiation. The patterning of Drosophila retina occurs both very fast and with high precision. This process is driven by the dynamic changes in signaling activity of the conserved Hedgehog (Hh) pathway, which coordinates cell fate determination, cell cycle and tissue morphogenesis. Here we show that during Drosophila retinogenesis, the retinal determination gene dachshund (dac) is not only a target of the Hh signaling pathway, but is also a modulator of its activity. Using developmental genetics techniques, we demonstrate that dac enhances Hh signaling by promoting the accumulation of the Gli transcription factor Cubitus interruptus (Ci) parallel to or downstream of fused. In the absence of dac, all Hh-mediated events associated to the morphogenetic furrow are delayed. One of the consequences is that, posterior to the furrow, dac- cells cannot activate a Roadkill-Cullin3 negative feedback loop that attenuates Hh signaling and which is necessary for retinal cells to continue normal differentiation. Therefore, dac is part of an essential positive feedback loop in the Hh pathway, guaranteeing the speed and the accuracy of Drosophila retinogenesis. PMID:27442438

  11. Mechanisms of systemic wound response in Drosophila.

    PubMed

    Lee, Won-Jae; Miura, Masayuki

    2014-01-01

    In response to cellular and tissue losses caused by physical or chemical injuries, organisms must activate multiple wound repair systems at the cellular, tissue, and organismal levels. The systemic wound response (SWR) that occurs via interorgan communication between local wound sites and remote organs ensures that the host is protected efficiently in response to a local wound. The local wound response around the wound site is fairly well documented, but the molecular mechanisms that allow the host to launch SWR are poorly understood. Recent studies on the Drosophila adult model system have shown that the local wound response is not restricted to the wound site because it plays an essential role in generating signals transmitted to remote organs that subsequently achieve SWR. By exploiting the genetic methods available for investigating Drosophila, we are just beginning to understand the complex interorgan networks that operate during SWRs. This review discusses the basic processes involved with classical integumental wound responses and tissue regeneration, such as epithelial cell movement, hemocyte recruitment, apoptosis, melanization, and generation of reactive oxygen species, as well as the recently described intestinal epithelial cell renewal program that occurs in response to gut cell damages. Furthermore, we discuss how these local wound responses integrate with organ-to-organ communication to launch SWR. Genetic analysis of SWRs using the Drosophila model system will provide a unique opportunity to dissect the molecular mechanisms that control wound-induced organ-to-organ communication. PMID:24512709

  12. Characterization and distribution of NKD, a receptor for Drosophila tachykinin-related peptide 6

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Neuropeptides related to vertebrate tachykinins have been identified in Drosophila and are referred to as drosotachykinins, or DTKs. Two Drosophila G protein-coupled receptors, designated NKD (neurokinin receptor from Drosophila; CG6515) and DTKR (Drosophila tachykinin receptor; CG7887), display seq...

  13. Drosophila suzukii population response to environment and management strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spotted wing drosophila, Drosophila suzukii, quickly emerged as a devastating invasive pest of small and stone fruits in the Americas and Europe. To better understand the population dynamics of D. suzukii, we reviewed recent work on juvenile development, adult reproduction, and seasonal variation in...

  14. Drosophila lacks C20 and C22 polyunsaturated fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drosophila melanogaster has been considered an ideal model organism to investigate human diseases and genetic pathways. Whether Drosophila is an ideal model for nutrigenomics, especially for fatty acid metabolism, however, remains to be illustrated. This study was to examine the metabolism of C20 an...

  15. Spotted wing drosophila: a new invasive pest of Mississippi berries

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spotted Wing Drosophila (SWD) Drosophila suzukii, a native fly of Southeast Asia, is a widely reported and highly invasive pest of fruit crops in North America and Mediterranean Europe. Between 2010 and 2011, SWD was confirmed in most States in eastern North America. During this same period, SWD was...

  16. Cranberries and Spotted Wing Drosophila (SWD) in Wisconsin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drosophila suzukii, commonly known as spotted wing drosophila (SWD), does not appear to like cranberries very much. Following multiple replicated trials using ripe, under-ripe, and over-ripe organic Wisconsin cranberries, SWD females would not (or could not) insert eggs into under-ripe or ripe cranb...

  17. Porphyromonas gingivalis-host interactions in a Drosophila melanogaster model.

    PubMed

    Igboin, Christina O; Tordoff, Kevin P; Moeschberger, Melvin L; Griffen, Ann L; Leys, Eugene J

    2011-01-01

    Porphyromonas gingivalis is a Gram-negative obligate anaerobe that has been implicated in the etiology of adult periodontitis. We recently introduced a Drosophila melanogaster killing model for examination of P. gingivalis-host interactions. In the current study, the Drosophila killing model was used to characterize the host response to P. gingivalis infection by identifying host components that play a role during infection. Drosophila immune response gene mutants were screened for altered susceptibility to killing by P. gingivalis. The Imd signaling pathway was shown to be important for the survival of Drosophila infected by nonencapsulated P. gingivalis strains but was dispensable for the survival of Drosophila infected by encapsulated P. gingivalis strains. The P. gingivalis capsule was shown to mediate resistance to killing by Drosophila antimicrobial peptides (Imd pathway-regulated cecropinA and drosocin) and human beta-defensin 3. Drosophila thiol-ester protein II (Tep II) and Tep IV and the tumor necrosis factor (TNF) homolog Eiger were also involved in the immune response against P. gingivalis infection, while the scavenger receptors Eater and Croquemort played no roles in the response to P. gingivalis infection. This study demonstrates that the Drosophila killing model is a useful high-throughput model for characterizing the host response to P. gingivalis infection and uncovering novel interactions between the bacterium and the host. PMID:21041486

  18. First foreign exploration for asian parasitoids of Drosophila suzukii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The invasive spotted wing drosophila, Drosophila suzukii Matsumura (Dipt.: Drosophilidae), is a native of East Asia and is now widely established in North America and Europe, where it is a serious pest of small and stone fruit crops. The lack of effective indigenous parasitoids of D. suzukii in the ...

  19. Susceptibility of cranberries to Drosophila suzukii (Diptera: Drosophilidae)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Drosophila suzukii Mastsumura (Diptera: Drosophilidae), commonly referred to as the spotted-wing drosophila, is an exotic species that has proven a troublesome pest of fruit production in the U.S. The fly targets small fruit and thus represents a concern for the U.S. cranberry industry. Two studies ...

  20. The developmental transcriptome of Drosophila melanogaster

    SciTech Connect

    University of Connecticut; Graveley, Brenton R.; Brooks, Angela N.; Carlson, Joseph W.; Duff, Michael O.; Landolin, Jane M.; Yang, Li; Artieri, Carlo G.; van Baren, Marijke J.; Boley, Nathan; Booth, Benjamin W.; Brown, James B.; Cherbas, Lucy; Davis, Carrie A.; Dobin, Alex; Li, Renhua; Lin, Wei; Malone, John H.; Mattiuzzo, Nicolas R.; Miller, David; Sturgill, David; Tuch, Brian B.; Zaleski, Chris; Zhang, Dayu; Blanchette, Marco; Dudoit, Sandrine; Eads, Brian; Green, Richard E.; Hammonds, Ann; Jiang, Lichun; Kapranov, Phil; Langton, Laura; Perrimon, Norbert; Sandler, Jeremy E.; Wan, Kenneth H.; Willingham, Aarron; Zhang, Yu; Zou, Yi; Andrews, Justen; Bicke, Peter J.; Brenner, Steven E.; Brent, Michael R.; Cherbas, Peter; Gingeras, Thomas R.; Hoskins, Roger A.; Kaufman, Thomas C.; Oliver, Brian; Celniker, Susan E.

    2010-12-02

    Drosophila melanogaster is one of the most well studied genetic model organisms; nonetheless, its genome still contains unannotated coding and non-coding genes, transcripts, exons and RNA editing sites. Full discovery and annotation are pre-requisites for understanding how the regulation of transcription, splicing and RNA editing directs the development of this complex organism. Here we used RNA-Seq, tiling microarrays and cDNA sequencing to explore the transcriptome in 30 distinct developmental stages. We identified 111,195 new elements, including thousands of genes, coding and non-coding transcripts, exons, splicing and editing events, and inferred protein isoforms that previously eluded discovery using established experimental, prediction and conservation-based approaches. These data substantially expand the number of known transcribed elements in the Drosophila genome and provide a high-resolution view of transcriptome dynamics throughout development. Drosophila melanogaster is an important non-mammalian model system that has had a critical role in basic biological discoveries, such as identifying chromosomes as the carriers of genetic information and uncovering the role of genes in development. Because it shares a substantial genic content with humans, Drosophila is increasingly used as a translational model for human development, homeostasis and disease. High-quality maps are needed for all functional genomic elements. Previous studies demonstrated that a rich collection of genes is deployed during the life cycle of the fly. Although expression profiling using microarrays has revealed the expression of, 13,000 annotated genes, it is difficult to map splice junctions and individual base modifications generated by RNA editing using such approaches. Single-base resolution is essential to define precisely the elements that comprise the Drosophila transcriptome. Estimates of the number of transcript isoforms are less accurate than estimates of the number of genes

  1. Discovery of Trypanosomatid Parasites in Globally Distributed Drosophila Species

    PubMed Central

    Chandler, James Angus; James, Pamela M.

    2013-01-01

    Microbial parasites of animals include bacteria, viruses, and various unicellular eukaryotes. Because of the difficulty in studying these microorganisms in both humans and disease vectors, laboratory models are commonly used for experimental analysis of host-parasite interactions. Drosophila is one such model that has made significant contributions to our knowledge of bacterial, fungal, and viral infections. Despite this, less is known about other potential parasites associated with natural Drosophila populations. Here, we surveyed sixteen Drosophila populations comprising thirteen species from four continents and Hawaii and found that they are associated with an extensive diversity of trypanosomatids (Euglenozoa, Kinetoplastea). Phylogenetic analysis finds that Drosophila-associated trypanosomatids are closely related to taxa that are responsible for various types of leishmaniases and more distantly related to the taxa responsible for human African trypanosomiasis and Chagas disease. We suggest that Drosophila may provide a powerful system for studying the interactions between trypanosomatids and their hosts. PMID:23658617

  2. An inventory of peroxisomal proteins and pathways in Drosophila melanogaster

    PubMed Central

    Faust, Joseph E.; Verma, Avani; Peng, Chengwei; McNew, James A.

    2012-01-01

    Peroxisomes are ubiquitous organelles housing a variety of essential biochemical pathways. Peroxisome dysfunction causes a spectrum of human diseases known as peroxisome biogenesis disorders (PBD). While much is known regarding the mechanism of peroxisome biogenesis, it is still unclear how peroxisome dysfunction leads to the disease state. Several recent studies have shown that mutations in Drosophila peroxin genes cause phenotypes similar to those seen in humans with PBDs suggesting that Drosophila might be a useful system to model PBDs. We have analyzed the proteome of Drosophila to identify the proteins involved in peroxisomal biogenesis and homeostasis as well as metabolic enzymes that function within the organelle. The subcellular localization of five of these predicted peroxisomal proteins was confirmed. Similar to C. elegans, Drosophila appears to only utilize the peroxisome targeting signal (PTS) type 1 system for matrix protein import. This work will further our understanding of peroxisomes in Drosophila and add to the usefulness of this emerging model system. PMID:22758915

  3. The influence of temperature and photoperiod on the reproductive diapause and cold tolerance of spotted-wing drosophila, Drosophila suzukii

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Knowledge regarding the reproductive status of spotted-wing drosophila, Drosophila suzukii (Matsumura)(Diptera: Drosophilidae) is of critical importance in predicting potential infestations of this invasive pest, as eggs are laid in ripe or ripening fruit of several commercially important small frui...

  4. Optimizing postharvest methyl bromide treatments to control spotted wing drosophila, Drosophila suzukii, in sweet cherries from Western USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Methyl bromide (MB) chamber fumigations were evaluated for postharvest control of spotted wing drosophila (SWD), Drosophila suzukii (Matsumura) (Diptera: Drosophilidae), in fresh sweet cherry exports from Western USA. Sweet cherries were infested with SWD, incubated to maximize numbers of the most M...

  5. Evolutionary relationships of Drosophila mojavensis geographic host races and their sister species Drosophila arizonae.

    PubMed

    Reed, L K; Nyboer, M; Markow, T A

    2007-03-01

    The cactophilic Drosophila mojavensis species group living in the deserts and dry tropical forests of the southwestern United States and Mexico provides a valuable system for studies in diversification and speciation. Rigorous studies of the relationships between host races of D. mojavensis and the relationships among the members of the species group (D. mojavensis, Drosophila arizona, and Drosophila navojoa) are lacking. We used mitochondrial CO1 sequence data to address the phylogenetics and population genetics of this species group. In this study we have found that the sister species D. mojavensis and D. arizonae share no mitochondrial haplotypes and thus show no evidence for recent introgression. We estimate the divergence time between D. mojavensis and D. arizonae to be between 1.91 and 2.97 million years ago. D. arizonae shows little structure in our population genetic analyses but there is phylogenetic differentiation between southeastern and northern populations of D. arizonae. Drosophila mojavensis shows significant population and phylogenetic structure across the four geographic regions of its distribution. The mitochondrial data support an origin of D. mojavensis on the mainland with early differentiation into the populations now found in the Mojave Desert and the Mainland Sonoran Desert and later colonization of the Baja Peninsula, in contrast to previous models. Also, the sister clade to D. mojavensis/D. arizonae includes D. navojoa and Drosophila huaylasi. By defining the genetic relationships among these populations, we provide a foundation for more sophisticated hypothesis testing regarding the timing of early speciation events and host switches in this species group. PMID:17305857

  6. Pheromones mediating copulation and attraction in Drosophila.

    PubMed

    Dweck, Hany K M; Ebrahim, Shimaa A M; Thoma, Michael; Mohamed, Ahmed A M; Keesey, Ian W; Trona, Federica; Lavista-Llanos, Sofia; Svatoš, Aleš; Sachse, Silke; Knaden, Markus; Hansson, Bill S

    2015-05-26

    Intraspecific olfactory signals known as pheromones play important roles in insect mating systems. In the model Drosophila melanogaster, a key part of the pheromone-detecting system has remained enigmatic through many years of research in terms of both its behavioral significance and its activating ligands. Here we show that Or47b-and Or88a-expressing olfactory sensory neurons (OSNs) detect the fly-produced odorants methyl laurate (ML), methyl myristate, and methyl palmitate. Fruitless (fru(M))-positive Or47b-expressing OSNs detect ML exclusively, and Or47b- and Or47b-expressing OSNs are required for optimal male copulation behavior. In addition, activation of Or47b-expressing OSNs in the male is sufficient to provide a competitive mating advantage. We further find that the vigorous male courtship displayed toward oenocyte-less flies is attributed to an oenocyte-independent sustained production of the Or47b ligand, ML. In addition, we reveal that Or88a-expressing OSNs respond to all three compounds, and that these neurons are necessary and sufficient for attraction behavior in both males and females. Beyond the OSN level, information regarding the three fly odorants is transferred from the antennal lobe to higher brain centers in two dedicated neural lines. Finally, we find that both Or47b- and Or88a-based systems and their ligands are remarkably conserved over a number of drosophilid species. Taken together, our results close a significant gap in the understanding of the olfactory background to Drosophila mating and attraction behavior; while reproductive isolation barriers between species are created mainly by species-specific signals, the mating enhancing signal in several Drosophila species is conserved. PMID:25964351

  7. Pheromones mediating copulation and attraction in Drosophila

    PubMed Central

    Dweck, Hany K. M.; Ebrahim, Shimaa A. M.; Thoma, Michael; Mohamed, Ahmed A. M.; Keesey, Ian W.; Trona, Federica; Lavista-Llanos, Sofia; Svatoš, Aleš; Sachse, Silke; Knaden, Markus; Hansson, Bill S.

    2015-01-01

    Intraspecific olfactory signals known as pheromones play important roles in insect mating systems. In the model Drosophila melanogaster, a key part of the pheromone-detecting system has remained enigmatic through many years of research in terms of both its behavioral significance and its activating ligands. Here we show that Or47b-and Or88a-expressing olfactory sensory neurons (OSNs) detect the fly-produced odorants methyl laurate (ML), methyl myristate, and methyl palmitate. Fruitless (fruM)-positive Or47b-expressing OSNs detect ML exclusively, and Or47b- and Or47b-expressing OSNs are required for optimal male copulation behavior. In addition, activation of Or47b-expressing OSNs in the male is sufficient to provide a competitive mating advantage. We further find that the vigorous male courtship displayed toward oenocyte-less flies is attributed to an oenocyte-independent sustained production of the Or47b ligand, ML. In addition, we reveal that Or88a-expressing OSNs respond to all three compounds, and that these neurons are necessary and sufficient for attraction behavior in both males and females. Beyond the OSN level, information regarding the three fly odorants is transferred from the antennal lobe to higher brain centers in two dedicated neural lines. Finally, we find that both Or47b- and Or88a-based systems and their ligands are remarkably conserved over a number of drosophilid species. Taken together, our results close a significant gap in the understanding of the olfactory background to Drosophila mating and attraction behavior; while reproductive isolation barriers between species are created mainly by species-specific signals, the mating enhancing signal in several Drosophila species is conserved. PMID:25964351

  8. The Drosophila EKC/KEOPS complex

    PubMed Central

    Rojas-Benítez, Diego; Ibar, Consuelo; Glavic, Álvaro

    2013-01-01

    The TOR signaling pathway is crucial in the translation of nutritional inputs into the protein synthesis machinery regulation, allowing animal growth. We recently identified the Bud32 (yeast)/PRPK (human) ortholog in Drosophila, Prpk (p53-related protein kinase), and found that it is required for TOR kinase activity. Bud32/PRPK is an ancient and atypical kinase conserved in evolution from Archeae to humans, being essential for Archeae. It has been linked with p53 stabilization in human cell culture and its absence in yeast causes a slow-growth phenotype. This protein has been associated to KEOPS (kinase, putative endopeptidase and other proteins of small size) complex together with Kae1p (ATPase), Cgi-121 and Pcc1p. This complex has been implicated in telomere maintenance, transcriptional regulation, bud site selection and chemical modification of tRNAs (tRNAs). Bud32p and Kae1p have been related with N6-threonylcarbamoyladenosine (t6A) synthesis, a particular chemical modification that occurs at position 37 of tRNAs that pair A-starting codons, required for proper translation in most species. Lack of this modification causes mistranslations and open reading frame shifts in yeast. The core constituents of the KEOPS complex are present in Drosophila, but their physical interaction has not been reported yet. Here, we present a review of the findings regarding the function of this complex in different organisms and new evidence that extends our recent observations of Prpk function in animal growth showing that depletion of Kae1 or Prpk, in accordance with their role in translation in yeast, is able to induce the unfolded protein response (UPR) in Drosophila. We suggest that EKC/KEOPS complex could be integrating t6A-modified tRNA availability with translational rates, which are ultimately reflected in animal growth. PMID:23823807

  9. Drosophila melanogaster deoxyribonucleoside kinase activates gemcitabine

    SciTech Connect

    Knecht, Wolfgang; Mikkelsen, Nils Egil; Clausen, Anders Ranegaard; Willer, Mette; Gojkovic, Zoran

    2009-05-01

    Drosophila melanogaster multisubstrate deoxyribonucleoside kinase (Dm-dNK) can additionally sensitize human cancer cell lines towards the anti-cancer drug gemcitabine. We show that this property is based on the Dm-dNK ability to efficiently phosphorylate gemcitabine. The 2.2 A resolution structure of Dm-dNK in complex with gemcitabine shows that the residues Tyr70 and Arg105 play a crucial role in the firm positioning of gemcitabine by extra interactions made by the fluoride atoms. This explains why gemcitabine is a good substrate for Dm-dNK.

  10. Hypergravity-induced altered behavior in Drosophila

    NASA Astrophysics Data System (ADS)

    Hosamani, Ravikumar; Wan, Judy; Marcu, Oana; Bhattacharya, Sharmila

    2012-07-01

    Microgravity and mechanical stress are important factors of the spaceflight environment, and affect astronaut health and behavior. Structural, functional, and behavioral mechanisms of all cells and organisms are adapted to Earth's gravitational force, 1G, while altered gravity can pose challenges to their adaptability to this new environment. On ground, hypergravity paradigms have been used to predict and complement studies on microgravity. Even small changes that take place at a molecular and genetic level during altered gravity may result in changes in phenotypic behavior. Drosophila provides a robust and simple, yet very reliable model system to understand the complexity of hypergravity-induced altered behavior, due to availability of a plethora of genetic tools. Locomotor behavior is a sensitive parameter that reflects the array of molecular adaptive mechanisms recruited during exposure to altered gravity. Thus, understanding the genetic basis of this behavior in a hypergravity environment could potentially extend our understanding of mechanisms of adaptation in microgravity. In our laboratory we are trying to dissect out the cellular and molecular mechanisms underlying hypergravity-induced oxidative stress, and its potential consequences on behavioral alterations by using Drosophila as a model system. In the present study, we employed pan-neuronal and mushroom body specific knock-down adult flies by using Gal4/UAS system to express inverted repeat transgenes (RNAi) to monitor and quantify the hypergravity-induced behavior in Drosophila. We established that acute hypergravity (3G for 60 min) causes a significant and robust decrease in the locomotor behavior in adult Drosophila, and that this change is dependent on genes related to Parkinson's disease, such as DJ-1α , DJ-1β , and parkin. In addition, we also showed that anatomically the control of this behavior is significantly processed in the mushroom body region of the fly brain. This work links a molecular

  11. Spatiotemporal rescue of memory dysfunction in Drosophila.

    PubMed

    McGuire, Sean E; Le, Phuong T; Osborn, Alexander J; Matsumoto, Kunihiro; Davis, Ronald L

    2003-12-01

    We have developed a method for temporal and regional gene expression targeting (TARGET) in Drosophila and show the simultaneous spatial and temporal rescue of a memory defect. The transient expression of the rutabaga-encoded adenylyl cyclase in the mushroom bodies of the adult brain was necessary and sufficient to rescue the rutabaga memory deficit, which rules out a developmental brain defect in the etiology of this deficit and demonstrates an acute role for rutabaga in memory formation in these neurons. The TARGET system offers general utility in simultaneously addressing issues of when and where gene products are required. PMID:14657498

  12. Organ size control: lessons from Drosophila

    PubMed Central

    Hariharan, Iswar K.

    2015-01-01

    Of fundamental interest to biologists is how organs achieve a reproducible size during development. Studies of the developing Drosophila wing have provided many key insights that will help give a conceptual understanding of the process beyond the fly. In the wing, there is evidence for both “top-down” mechanisms, where signals emanating from small subsets of cells direct global proliferation, and “”bottom-up” mechanisms, where the final size is an emergent property of local cell-cell interactions. Mechanical forces also appear to have an important role along with the Hippo pathway, which may integrate multiple types of inputs to regulate the extent of growth. PMID:26267393

  13. Studying tauopathies in Drosophila: A fruitful model.

    PubMed

    Sun, Mingkuan; Chen, Liam

    2015-12-01

    Tauopathies are a group of neurodegenerative disorders that include hereditary frontotemporal dementias (FTDs) such as FTD with parkinsonism linked to chromosome 17 (FTDP-17), as well as sporadic variants of FTDs like progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), and Pick's disease. These diverse diseases all have in common the presence of abnormally phosphorylated tau aggregates. In this review, we will summarize key features of transgenic Drosophila models of tauopathies and a number of insights into disease mechanisms as well as therapeutic implications gained from the fruit fly models. PMID:25862286

  14. The intimate genetics of Drosophila fertilization

    PubMed Central

    Loppin, Benjamin; Dubruille, Raphaëlle; Horard, Béatrice

    2015-01-01

    The union of haploid gametes at fertilization initiates the formation of the diploid zygote in sexually reproducing animals. This founding event of embryogenesis includes several fascinating cellular and nuclear processes, such as sperm–egg cellular interactions, sperm chromatin remodelling, centrosome formation or pronuclear migration. In comparison with other aspects of development, the exploration of animal fertilization at the functional level has remained so far relatively limited, even in classical model organisms. Here, we have reviewed our current knowledge of fertilization in Drosophila melanogaster, with a special emphasis on the genes involved in the complex transformation of the fertilizing sperm nucleus into a replicated set of paternal chromosomes. PMID:26246493

  15. A connectionist model of the Drosophila blastoderm

    SciTech Connect

    Reinitz, J. . Dept. of Biological Sciences); Mjolsness, E. . Dept. of Computer Science); Sharp, D.H. . Theoretical Div.)

    1990-11-01

    The authors present a phenomenological modeling framework for development, and apply it to the network of segmentation genes operating in the blastoderm of Drosophila. Their purpose is to provide a systematic method for discovering and expressing correlations in experimental data on gene expression and other developmental processes. The modeling framework is based on a connectionist or neural net dynamics for biochemical regulators, coupled to grammatical rules which describe certain features of the birth, growth, and death of cells, synapses and other biological entities. They present preliminary numerical results regarding regulatory interactions between the genes Kruppel and knirps that demonstrate the potential utility of the model. 14 refs., 5 figs.

  16. Evolution of a Distinct Genomic Domain in Drosophila: Comparative Analysis of the Dot Chromosome in Drosophila melanogaster and Drosophila virilis

    PubMed Central

    Leung, Wilson; Shaffer, Christopher D.; Cordonnier, Taylor; Wong, Jeannette; Itano, Michelle S.; Slawson Tempel, Elizabeth E.; Kellmann, Elmer; Desruisseau, David Michael; Cain, Carolyn; Carrasquillo, Robert; Chusak, Tien M.; Falkowska, Katazyna; Grim, Kelli D.; Guan, Rui; Honeybourne, Jacquelyn; Khan, Sana; Lo, Louis; McGaha, Rebecca; Plunkett, Jevon; Richner, Justin M.; Richt, Ryan; Sabin, Leah; Shah, Anita; Sharma, Anushree; Singhal, Sonal; Song, Fine; Swope, Christopher; Wilen, Craig B.; Buhler, Jeremy; Mardis, Elaine R.; Elgin, Sarah C. R.

    2010-01-01

    The distal arm of the fourth (“dot”) chromosome of Drosophila melanogaster is unusual in that it exhibits an amalgamation of heterochromatic properties (e.g., dense packaging, late replication) and euchromatic properties (e.g., gene density similar to euchromatic domains, replication during polytenization). To examine the evolution of this unusual domain, we undertook a comparative study by generating high-quality sequence data and manually curating gene models for the dot chromosome of D. virilis (Tucson strain 15010–1051.88). Our analysis shows that the dot chromosomes of D. melanogaster and D. virilis have higher repeat density, larger gene size, lower codon bias, and a higher rate of gene rearrangement compared to a reference euchromatic domain. Analysis of eight “wanderer” genes (present in a euchromatic chromosome arm in one species and on the dot chromosome in the other) shows that their characteristics are similar to other genes in the same domain, which suggests that these characteristics are features of the domain and are not required for these genes to function. Comparison of this strain of D. virilis with the strain sequenced by the Drosophila 12 Genomes Consortium (Tucson strain 15010–1051.87) indicates that most genes on the dot are under weak purifying selection. Collectively, despite the heterochromatin-like properties of this domain, genes on the dot evolve to maintain function while being responsive to changes in their local environment. PMID:20479145

  17. Drosophila-associated yeast species in vineyard ecosystems.

    PubMed

    Lam, Samuel S T H; Howell, Kate S

    2015-10-01

    Yeast activity during wine fermentation directly contributes to wine quality, but the source and movement of yeasts in vineyards and winery environments have not been resolved. Here, we investigate the yeast species associated with the Drosophila insect vector to help understand yeast dispersal and persistence. Drosophila are commonly found in vineyards and are known to have a mutualistic relationship with yeasts in other ecosystems. Drosophilids were collected from vineyards, grape waste (marc) piles and wineries during grape harvest. Captured flies were identified morphologically, and their associated yeasts were identified. Drosophila melanogaster/D. simulans, D. hydei and Scaptodrosophila lativittata were identified in 296 captured Drosophila flies. These flies were associated with Metschnikowia pulcherrima, Hanseniaspora uvarum, Torulaspora delbrueckii and H. valbyensis yeasts. Yeast and Drosophila species diversity differed between collection locations (vineyard and marc: R = 0.588 for Drosophila and R = 0.644 for yeasts). Surprisingly, the primary wine fermentation yeast, Saccharomyces cerevisiae, was not isolated. Drosophila flies are preferentially associated with different yeast species in the vineyard and winery environments, and this association may help the movement and dispersal of yeast species in the vineyard and winery ecosystem. PMID:26391524

  18. Evidence for horizontal transfer of Wolbachia by a Drosophila mite.

    PubMed

    Brown, Amy N; Lloyd, Vett K

    2015-07-01

    Mites are common ectoparasites of Drosophila and have been implicated in bacterial and mobile element invasion of Drosophila stocks. The obligate endobacterium, Wolbachia, has widespread effects on gene expression in their arthropod hosts and alters host reproduction to enhance its survival and propagation, often with deleterious effects in Drosophila hosts. To determine whether Wolbachia could be transferred between Drosophila melanogaster laboratory stocks by the mite Tyrophagus putrescentiae, mites were introduced to Wolbachia-infected Drosophila vials. These vials were kept adjacent to mite-free and Wolbachia-uninfected Drosophila stock vials. The Wolbachia infection statuses of the infected and uninfected flies were checked from generation 1 to 5. Results indicate that Wolbachia DNA could be amplified from mites infesting Wolbachia-infected fly stocks and infection in the previously uninfected stocks arose within generation 1 or 2, concomitant with invasion of mites from the Wolbachia-infected stock. A possible mechanism for the transfer of Wolbachia from flies to mites and vice versa, can be inferred from time-lapse photography of fly and mite interactions. We demonstrated that mites ingest Drosophila corpses, including Wolbachia-infected corpses, and Drosophila larva ingest mites, providing possible sources of Wolbachia infection and transfer. This research demonstrated that T. putrescentiae white mites can facilitate Wolbachia transfer between Drosophila stocks and that this may occur by ingestion of infected corpses. Mite-vectored Wolbachia transfer allows for rapid establishment of Wolbachia infection within a new population. This mode of Wolbachia introduction may be relevant in nature as well as in the laboratory, and could have a variety of biological consequences. PMID:25921489

  19. A novel, tissue-specific, Drosophila homeobox gene.

    PubMed Central

    Barad, M; Jack, T; Chadwick, R; McGinnis, W

    1988-01-01

    The homeobox gene family of Drosophila appears to control a variety of position-specific patterning decisions during embryonic and imaginal development. Most of these patterning decisions determine groups of cells on the anterior-posterior axis of the Drosophila germ band. We have isolated a novel homeobox gene from Drosophila, designated H2.0. H2.0 has the most diverged homeobox so far characterized in metazoa, and, in contrast to all previously isolated homeobox genes, H2.0 exhibits a tissue-specific pattern of expression. The cells that accumulate transcripts for this novel gene correspond to the visceral musculature and its anlagen. Images PMID:2901348

  20. Genetic effects of plutonium in Drosophila. Final technical report

    SciTech Connect

    1995-07-01

    This three year project, initiated in 1987, involved the genetic effects of alpha radiations on Drosophila. This document represents the final technical report. Plutonium residue was used as the alpha source of radon gas. Spontaneous mutation frequency in the Drosophila stock was very low. In the experiments using alpha radiation from radon gas, radiation doses as low as 20R induced significant numbers of mutations, with higher numbers of mutations at higher doses. If X-ray induced mutation frequencies reported in the literature are used for comparison, it can be concluded that alpha radiation from radon gas induces at least 2 to 3 time more mutations in Drosophila.

  1. Drosophila melanogaster as a Model System to Study Mitochondrial Biology

    PubMed Central

    Fernández-Moreno, Miguel Angel; Farr, Carol L.; Kaguni, Laurie S.; Garesse, Rafael

    2016-01-01

    Summary Mitochondria play an essential role in cellular homeostasis. Although in the last few decades our knowledge of mitochondria has increased substantially, the mechanisms involved in the control of mitochondrial biogenesis remain largely unknown. The powerful genetics of Drosophila combined with a wealth of available cell and molecular biology techniques, make this organism an excellent system to study mitochondria. In this chapter we will review briefly the opportunities that Drosophila offers as a model system and describe in detail how to purify mitochondria from Drosophila and to perform the analysis of developmental gene expression using in situ hybridization. PMID:18314716

  2. The Berkeley Drosophila Genome Project gene disruption project: Single P-element insertions mutating 25% of vital Drosophila genes.

    PubMed Central

    Spradling, A C; Stern, D; Beaton, A; Rhem, E J; Laverty, T; Mozden, N; Misra, S; Rubin, G M

    1999-01-01

    A fundamental goal of genetics and functional genomics is to identify and mutate every gene in model organisms such as Drosophila melanogaster. The Berkeley Drosophila Genome Project (BDGP) gene disruption project generates single P-element insertion strains that each mutate unique genomic open reading frames. Such strains strongly facilitate further genetic and molecular studies of the disrupted loci, but it has remained unclear if P elements can be used to mutate all Drosophila genes. We now report that the primary collection has grown to contain 1045 strains that disrupt more than 25% of the estimated 3600 Drosophila genes that are essential for adult viability. Of these P insertions, 67% have been verified by genetic tests to cause the associated recessive mutant phenotypes, and the validity of most of the remaining lines is predicted on statistical grounds. Sequences flanking >920 insertions have been determined to exactly position them in the genome and to identify 376 potentially affected transcripts from collections of EST sequences. Strains in the BDGP collection are available from the Bloomington Stock Center and have already assisted the research community in characterizing >250 Drosophila genes. The likely identity of 131 additional genes in the collection is reported here. Our results show that Drosophila genes have a wide range of sensitivity to inactivation by P elements, and provide a rationale for greatly expanding the BDGP primary collection based entirely on insertion site sequencing. We predict that this approach can bring >85% of all Drosophila open reading frames under experimental control. PMID:10471706

  3. Magnetoreception Regulates Male Courtship Activity in Drosophila

    PubMed Central

    Wu, Chia-Lin; Fu, Tsai-Feng; Chiang, Meng-Hsuan; Chang, Yu-Wei; Her, Jim-Long; Wu, Tony

    2016-01-01

    The possible neurological and biophysical effects of magnetic fields on animals is an area of active study. Here, we report that courtship activity of male Drosophila increases in a magnetic field and that this effect is regulated by the blue light-dependent photoreceptor cryptochrome (CRY). Naïve male flies exhibited significantly increased courtship activities when they were exposed to a ≥ 20-Gauss static magnetic field, compared with their behavior in the natural environment (0 Gauss). CRY-deficient flies, cryb and crym, did not show an increased courtship index in a magnetic field. RNAi-mediated knockdown of cry in cry-GAL4-positive neurons disrupted the increased male courtship activity in a magnetic field. Genetically expressing cry under the control of cry-GAL4 in the CRY-deficient flies restored the increase in male courtship index that occurred in a magnetic field. Interestingly, artificially activating cry-GAL4-expressing neurons, which include large ventral lateral neurons and small ventral lateral neurons, via expression of thermosensitive cation channel dTrpA1, also increased the male courtship index. This enhancement was abolished by the addition of the cry-GAL80 transgene. Our results highlight the phenomenon of increased male courtship activity caused by a magnetic field through CRY-dependent magnetic sensation in CRY expression neurons in Drosophila. PMID:27195955

  4. Contribution of Drosophila TRPA1 to Metabolism

    PubMed Central

    Lee, Jung-Eun; Kim, Yunjung; Kim, Kyoung Heon

    2016-01-01

    Transient receptor potential (TRP) cation channels are highly conserved in humans and insects. Some of these channels are expressed in internal organs and their functions remain incompletely understood. By direct knock-in of the GAL4 gene into the trpA1 locus in Drosophila, we identified the expression of this gene in the subesophageal ganglion (SOGs) region. In addition, the neurites present in the dorsal posterior region as well as the drosophila insulin-like peptide 2 (dILP2)-positive neurons send signals to the SOGs. The signal is sent to the crop, which is an enlarged organ of the esophagus and functions as a storage place for food in the digestive system. To systematically investigate the role of TRPA1 in metabolism, we applied non-targeted metabolite profiling analysis together with gas-chromatography/time-of-flight mass spectrometry, with an aim to identify a wide range of primary metabolites. We effectively captured distinctive metabolomic phenotypes and identified specific metabolic dysregulation triggered by TRPA1 mutation based on reconstructed metabolic network analysis. Primarily, the network analysis pinpointed the simultaneous down-regulation of intermediates in the methionine salvation pathway, in contrast to the synchronized up-regulation of a range of free fatty acids. The gene dosage-dependent dynamics of metabolite levels among wild-type, hetero- and homozygous mutants, and their coordinated metabolic modulation under multiple gene settings across five different genotypes confirmed the direct linkages of TRPA1 to metabolism. PMID:27055172

  5. Peptidoglycan recognition by the Drosophila Imd pathway.

    PubMed

    Kaneko, Takashi; Golenbock, Douglas; Silverman, Neal

    2005-01-01

    The structural requirements for recognition of peptidoglycan (PGN) by PGRP-LC and activation of the Drosophila IMD pathway are not yet clear. In order to examine this question more carefully, the activity of peptidoglycan from different types of bacteria was compared in cell-based and whole animal assays. Drosophila S2* cells, but not adult flies, responded to Lys-type Micrococcus luteus PGN, but with significantly less potency compared to Dap-type Escherichia coli PGN, while intact Lys-type PGN from Staphylococcus aureus was inactive. After treatment with lysostaphin, which digests the cross-bridging peptides, S. aureus PGN weakly stimulated the IMD pathway, similar to M. luteus PGN. Further digestion with mutanolysin, which creates monomeric PGN fragments, abolished the activity of S. aureus PGN. On the other hand, monomeric E. coli PGN, generated by mutanolysin digestion, was still active but required different isoforms of PGRP-LC for recognition. Polymeric PGN required only PGRP-LCx, while monomeric E. coli PGN required both the PGRP-LCa and PGRP-LCx isoforms. These results suggest that the recognition by PGRP-LCx alone requires polymeric PGN, and that polymeric Dap-type PGN is a more potent PGRP-LCx agonist, compared to Lys-type PGN. These results also suggest that the heteromeric PGRP-LCa/LCx receptor complex recognizes monomeric Dap-type, but not Lys-type, PGN. PMID:16303095

  6. Localization and possible functions of Drosophila septins.

    PubMed Central

    Fares, H; Peifer, M; Pringle, J R

    1995-01-01

    The septins are a family of homologous proteins that were originally identified in Saccharomyces cerevisiae, where they are associated with the "neck filaments" and are involved in cytokinesis and other aspects of the organization of the cell surface. We report here the identification of Sep1, a Drosophila melanogaster septin, based on its homology to the yeast septins. The predicted Sep1 amino acid sequence is 35-42% identical to the known S. cerevisiae septins; 52% identical to Pnut, a second D. melanogaster septin; and 53-73% identical to the known mammalian septins. Sep1-specific antibodies have been used to characterize its expression and localization. The protein is concentrated at the leading edge of the cleavage furrows of dividing cells and cellularizing embryos, suggesting a role in furrow formation. Other aspects of Sep1 localization suggest roles not directly related to cytokinesis. For example, Sep1 exhibits orderly, cell-cycle-coordinated rearrangements within the cortex of syncytial blastoderm embryos and in the cells of post-gastrulation embryos; Sep1 is also concentrated at the leading edge of the epithelium during dorsal closure in the embryo, in the neurons of the embryonic nervous system, and at the baso-lateral surfaces of ovarian follicle cells. The distribution of Sep1 typically overlaps, but is distinct from, that of actin. Both immunolocalization and biochemical experiments show that Sep1 is intimately associated with Pnut, suggesting that the Drosophila septins, like those in yeast, function as part of a complex. Images PMID:8590810

  7. Recombineering homologous recombination constructs in Drosophila.

    PubMed

    Carreira-Rosario, Arnaldo; Scoggin, Shane; Shalaby, Nevine A; Williams, Nathan David; Hiesinger, P Robin; Buszczak, Michael

    2013-01-01

    The continued development of techniques for fast, large-scale manipulation of endogenous gene loci will broaden the use of Drosophila melanogaster as a genetic model organism for human-disease related research. Recent years have seen technical advancements like homologous recombination and recombineering. However, generating unequivocal null mutations or tagging endogenous proteins remains a substantial effort for most genes. Here, we describe and demonstrate techniques for using recombineering-based cloning methods to generate vectors that can be used to target and manipulate endogenous loci in vivo. Specifically, we have established a combination of three technologies: (1) BAC transgenesis/recombineering, (2) ends-out homologous recombination and (3) Gateway technology to provide a robust, efficient and flexible method for manipulating endogenous genomic loci. In this protocol, we provide step-by-step details about how to (1) design individual vectors, (2) how to clone large fragments of genomic DNA into the homologous recombination vector using gap repair, and (3) how to replace or tag genes of interest within these vectors using a second round of recombineering. Finally, we will also provide a protocol for how to mobilize these cassettes in vivo to generate a knockout, or a tagged gene via knock-in. These methods can easily be adopted for multiple targets in parallel and provide a means for manipulating the Drosophila genome in a timely and efficient manner. PMID:23893070

  8. Cellular Mechanisms of Drosophila Heart Morphogenesis

    PubMed Central

    Vogler, Georg; Bodmer, Rolf

    2015-01-01

    Many of the major discoveries in the fields of genetics and developmental biology have been made using the fruit fly, Drosophila melanogaster. With regard to heart development, the conserved network of core cardiac transcription factors that underlies cardiogenesis has been studied in great detail in the fly, and the importance of several signaling pathways that regulate heart morphogenesis, such as Slit/Robo, was first shown in the fly model. Recent technological advances have led to a large increase in the genomic data available from patients with congenital heart disease (CHD). This has highlighted a number of candidate genes and gene networks that are potentially involved in CHD. To validate genes and genetic interactions among candidate CHD-causing alleles and to better understand heart formation in general are major tasks. The specific limitations of the various cardiac model systems currently employed (mammalian and fish models) provide a niche for the fly model, despite its evolutionary distance to vertebrates and humans. Here, we review recent advances made using the Drosophila embryo that identify factors relevant for heart formation. These underline how this model organism still is invaluable for a better understanding of CHD. PMID:26236710

  9. Microarray analysis of immune challenged Drosophila hemocytes.

    PubMed

    Johansson, Karin C; Metzendorf, Christoph; Söderhäll, Kenneth

    2005-04-15

    Insect hemocytes play multiple roles in immunity and carry out cellular responses like phagocytosis, encapsulation and melanization as well as producing humoral effector proteins in the first line of defense after injury and invasion of microorganisms. In this work, we used the Drosophila melanogaster hemocyte-like cell line mbn-2 and Affymetrix Drosophila GeneChips to investigate the transcriptome of a single type of immune competent tissue exposed to Gram-negative cell wall components (crude LPS) or high dose infection with live Escherichia coli. We found that gene expression profiles of both treatments overlap but show important differences in expression levels of several genes involved in immunity. In addition, cell morphology during infection was monitored and revealed distinct alterations in cell shape and adhesion. Presence of large numbers of bacteria also increased the number of cells taking on crystal cell fate. Taken together, our results indicate that hemocytes sense and respond differently to purified bacterial surface molecules and infection with live and actively growing bacteria both at the level of gene expression and in cell behavior. PMID:15777795

  10. The Eye Specification Network in Drosophila

    PubMed Central

    WEASNER, BRANDON P.; ANDERSON, JASON; KUMAR, JUSTIN P.

    2010-01-01

    One of the most exciting revelations in retinal biology is the realization that the molecules and mechanisms that regulate eye development have been conserved in all seeing animals including such diverse organisms as the fruit fly, mouse and man. The emerging commonality among mechanisms used in eye development allows for the use of model systems such as the fruit fly, Drosophila melanogaster, to provide key insights into the development and diseases of the mammalian eye. Eye specification in Drosophila is controlled, in part, by the concerted activities of eight nuclear proteins and several signal transduction cascades that together form a tightly woven regulatory network. Loss of function mutations in several components lead to the complete derailment of eye development while ectopic expression of threse genes in non-retinal tissues can direct the fates of these tissues towards eye formation. Here we will describe what is currently known about this remarkable regulatory cassettee highlight some of the outstanding questions that still need to be answered. PMID:25580038

  11. A dynamic deep sleep stage in Drosophila.

    PubMed

    van Alphen, Bart; Yap, Melvyn H W; Kirszenblat, Leonie; Kottler, Benjamin; van Swinderen, Bruno

    2013-04-17

    How might one determine whether simple animals such as flies sleep in stages? Sleep in mammals is a dynamic process involving different stages of sleep intensity, and these are typically associated with measurable changes in brain activity (Blake and Gerard, 1937; Rechtschaffen and Kales, 1968; Webb and Agnew, 1971). Evidence for different sleep stages in invertebrates remains elusive, even though it has been well established that many invertebrate species require sleep (Campbell and Tobler, 1984; Hendricks et al., 2000; Shaw et al., 2000; Sauer et al., 2003). Here we used electrophysiology and arousal-testing paradigms to show that the fruit fly, Drosophila melanogaster, transitions between deeper and lighter sleep within extended bouts of inactivity, with deeper sleep intensities after ∼15 and ∼30 min of inactivity. As in mammals, the timing and intensity of these dynamic sleep processes in flies is homeostatically regulated and modulated by behavioral experience. Two molecules linked to synaptic plasticity regulate the intensity of the first deep sleep stage. Optogenetic upregulation of cyclic adenosine monophosphate during the day increases sleep intensity at night, whereas loss of function of a molecule involved in synaptic pruning, the fragile-X mental retardation protein, increases sleep intensity during the day. Our results show that sleep is not homogenous in insects, and suggest that waking behavior and the associated synaptic plasticity mechanisms determine the timing and intensity of deep sleep stages in Drosophila. PMID:23595750

  12. Selective anticancer agents suppress aging in Drosophila.

    PubMed

    Danilov, Anton; Shaposhnikov, Mikhail; Plyusnina, Ekaterina; Kogan, Valeria; Fedichev, Peter; Moskalev, Alexey

    2013-09-01

    Mutations of the PI3K, TOR, iNOS, and NF-κB genes increase lifespan of model organisms and reduce the risk of some aging-associated diseases. We studied the effects of inhibitors of PI3K (wortmannin), TOR (rapamycin), iNOS (1400W), NF-κB (pyrrolidin dithiocarbamate and QNZ), and the combined effects of inhibitors: PI3K (wortmannin) and TOR (rapamycin), NF-κB (pyrrolidin dithiocarbamates) and PI3K (wortmannin), NF-κB (pyrrolidine dithiocarbamates) and TOR (rapamycin) on Drosophila melanogaster lifespan and quality of life (locomotor activity and fertility). Our data demonstrate that pharmacological inhibition of PI3K, TOR, NF-κB, and iNOS increases lifespan of Drosophila without decreasing quality of life. The greatest lifespan expanding effect was achieved by a combination of rapamycin (5 μM) and wortmannin (5 μM) (by 23.4%). The bioinformatic analysis (KEGG, REACTOME.PATH, DOLite, and GO.BP) showed the greatest aging-suppressor activity of rapamycin, consistent with experimental data. PMID:24096697

  13. Dissection of larval CNS in Drosophila melanogaster.

    PubMed

    Hafer, Nathaniel; Schedl, Paul

    2006-12-01

    The central nervous system (CNS) of Drosophila larvae is complex and poorly understood. One way to investigate the CNS is to use immunohistochemistry to examine the expression of various novel and marker proteins. Staining of whole larvae is impractical because the tough cuticle prevents antibodies from penetrating inside the body cavity. In order to stain these tissues it is necessary to dissect the animal prior to fixing and staining. In this article we demonstrate how to dissect Drosophila larvae without damaging the CNS. Begin by tearing the larva in half with a pair of fine forceps, and then turn the cuticle "inside-out" to expose the CNS. If the dissection is performed carefully the CNS will remain attached to the cuticle. We usually keep the CNS attached to the cuticle throughout the fixation and staining steps, and only completely remove the CNS from the cuticle just prior to mounting the samples on glass slides. We also show some representative images of a larval CNS stained with Eve, a transcription factor expressed in a subset of neurons in the CNS. The article concludes with a discussion of some of the practical uses of this technique and the potential difficulties that may arise. PMID:18704179

  14. Contribution of Drosophila TRPA1 to Metabolism.

    PubMed

    Lee, Jung-Eun; Kim, Yunjung; Kim, Kyoung Heon; Lee, Do Yup; Lee, Youngseok

    2016-01-01

    Transient receptor potential (TRP) cation channels are highly conserved in humans and insects. Some of these channels are expressed in internal organs and their functions remain incompletely understood. By direct knock-in of the GAL4 gene into the trpA1 locus in Drosophila, we identified the expression of this gene in the subesophageal ganglion (SOGs) region. In addition, the neurites present in the dorsal posterior region as well as the drosophila insulin-like peptide 2 (dILP2)-positive neurons send signals to the SOGs. The signal is sent to the crop, which is an enlarged organ of the esophagus and functions as a storage place for food in the digestive system. To systematically investigate the role of TRPA1 in metabolism, we applied non-targeted metabolite profiling analysis together with gas-chromatography/time-of-flight mass spectrometry, with an aim to identify a wide range of primary metabolites. We effectively captured distinctive metabolomic phenotypes and identified specific metabolic dysregulation triggered by TRPA1 mutation based on reconstructed metabolic network analysis. Primarily, the network analysis pinpointed the simultaneous down-regulation of intermediates in the methionine salvation pathway, in contrast to the synchronized up-regulation of a range of free fatty acids. The gene dosage-dependent dynamics of metabolite levels among wild-type, hetero- and homozygous mutants, and their coordinated metabolic modulation under multiple gene settings across five different genotypes confirmed the direct linkages of TRPA1 to metabolism. PMID:27055172

  15. Genetic analysis of glutamatergic function in Drosophila

    SciTech Connect

    Chase, B.A.; Kankel, D.R.

    1987-01-01

    Neurotransmitters are essential for communication between neurons and hence are vital in the overall integrative functioning of the nervous system. Previous work on acetylcholine metabolism in the fruit fly, Drosophila melanogaster, has also raised the possibility that transmitter metabolism may play a prominent role in either the achievement or maintenance of the normal structure of the central nervous system in this species. Unfortunately, acetylcholine is rather poorly characterized as a neurotransmitter in Drosophila; consequently, we have begun an analysis of the role of glutamate (probably the best characterized transmitter in this organism) in the formation and/or maintenance of nervous system structure. We present here the results of a series of preliminary analyses. To suggest where glutamatergic function may be localized, an examination of the spatial distribution of high affinity (/sup 3/H)-glutamate binding sites are presented. We present the results of an analysis of the spatial and temporal distribution of enzymatic activities thought to be important in the regulation of transmitter-glutamate pools (i.e., glutamate oxaloacetic transaminase, glutaminase, and glutamate dehydrogenase). To begin to examine whether mutations in any of these functions are capable of affecting glutamatergic activity, we present the results of an initial genetic analysis of one enzymatic function, glutamate oxaloacetic transaminase (GOT), chosen because of its differential distribution within the adult central nervous system and musculature.

  16. Loading Drosophila nerve terminals with calcium indicators.

    PubMed

    Rossano, Adam J; Macleod, Gregory T

    2007-01-01

    Calcium plays many roles in the nervous system but none more impressive than as the trigger for neurotransmitter release, and none more profound than as the messenger essential for the synaptic plasticity that supports learning and memory. To further elucidate the molecular underpinnings of Ca(2+)-dependent synaptic mechanisms, a model system is required that is both genetically malleable and physiologically accessible. Drosophila melanogaster provides such a model. In this system, genetically-encoded fluorescent indicators are available to detect Ca(2+) changes in nerve terminals. However, these indicators have limited sensitivity to Ca(2+) and often show a non-linear response. Synthetic fluorescent indicators are better suited for measuring the rapid Ca(2+) changes associated with nerve activity. Here we demonstrate a technique for loading dextran-conjugated synthetic Ca(2+) indicators into live nerve terminals in Drosophila larvae. Particular emphasis is placed on those aspects of the protocol most critical to the technique's success, such as how to avoid static electricity discharges along the isolated nerves, maintaining the health of the preparation during extended loading periods, and ensuring axon survival by providing Ca(2+) to promote sealing of severed axon endings. Low affinity dextran-conjugated Ca(2+)-indicators, such as fluo-4 and rhod, are available which show a high signal-to-noise ratio while minimally disrupting presynaptic Ca(2+) dynamics. Dextran-conjugation helps prevent Ca(2+) indicators being sequestered into organelles such as mitochondria. The loading technique can be applied equally to larvae, embryos and adults. PMID:18997898

  17. Imaging fictive locomotor patterns in larval Drosophila.

    PubMed

    Pulver, Stefan R; Bayley, Timothy G; Taylor, Adam L; Berni, Jimena; Bate, Michael; Hedwig, Berthold

    2015-11-01

    We have established a preparation in larval Drosophila to monitor fictive locomotion simultaneously across abdominal and thoracic segments of the isolated CNS with genetically encoded Ca(2+) indicators. The Ca(2+) signals closely followed spiking activity measured electrophysiologically in nerve roots. Three motor patterns are analyzed. Two comprise waves of Ca(2+) signals that progress along the longitudinal body axis in a posterior-to-anterior or anterior-to-posterior direction. These waves had statistically indistinguishable intersegmental phase delays compared with segmental contractions during forward and backward crawling behavior, despite being ∼10 times slower. During these waves, motor neurons of the dorsal longitudinal and transverse muscles were active in the same order as the muscle groups are recruited during crawling behavior. A third fictive motor pattern exhibits a left-right asymmetry across segments and bears similarities with turning behavior in intact larvae, occurring equally frequently and involving asymmetry in the same segments. Ablation of the segments in which forward and backward waves of Ca(2+) signals were normally initiated did not eliminate production of Ca(2+) waves. When the brain and subesophageal ganglion (SOG) were removed, the remaining ganglia retained the ability to produce both forward and backward waves of motor activity, although the speed and frequency of waves changed. Bilateral asymmetry of activity was reduced when the brain was removed and abolished when the SOG was removed. This work paves the way to studying the neural and genetic underpinnings of segmentally coordinated motor pattern generation in Drosophila with imaging techniques. PMID:26311188

  18. Thermosensory processing in the Drosophila brain.

    PubMed

    Liu, Wendy W; Mazor, Ofer; Wilson, Rachel I

    2015-03-19

    In Drosophila, just as in vertebrates, changes in external temperature are encoded by bidirectional opponent thermoreceptor cells: some cells are excited by warming and inhibited by cooling, whereas others are excited by cooling and inhibited by warming. The central circuits that process these signals are not understood. In Drosophila, a specific brain region receives input from thermoreceptor cells. Here we show that distinct genetically identified projection neurons (PNs) in this brain region are excited by cooling, warming, or both. The PNs excited by cooling receive mainly feed-forward excitation from cool thermoreceptors. In contrast, the PNs excited by warming ('warm-PNs') receive both excitation from warm thermoreceptors and crossover inhibition from cool thermoreceptors through inhibitory interneurons. Notably, this crossover inhibition elicits warming-evoked excitation, because warming suppresses tonic activity in cool thermoreceptors. This in turn disinhibits warm-PNs and sums with feed-forward excitation evoked by warming. Crossover inhibition could cancel non-thermal activity (noise) that is positively correlated among warm and cool thermoreceptor cells, while reinforcing thermal activity which is anti-correlated. Our results show how central circuits can combine signals from bidirectional opponent neurons to construct sensitive and robust neural codes. PMID:25739502

  19. Selective anticancer agents suppress aging in Drosophila

    PubMed Central

    Danilov, Anton; Shaposhnikov, Mikhail; Plyusnina, Ekaterina; Kogan, Valeria; Fedichev, Peter; Moskalev, Alexey

    2013-01-01

    Mutations of the PI3K, TOR, iNOS, and NF-κB genes increase lifespan of model organisms and reduce the risk of some aging-associated diseases. We studied the effects of inhibitors of PI3K (wortmannin), TOR (rapamycin), iNOS (1400W), NF-κB (pyrrolidin dithiocarbamate and QNZ), and the combined effects of inhibitors: PI3K (wortmannin) and TOR (rapamycin), NF-κB (pyrrolidin dithiocarbamates) and PI3K (wortmannin), NF-κB (pyrrolidine dithiocarbamates) and TOR (rapamycin) on Drosophila melanogaster lifespan and quality of life (locomotor activity and fertility). Our data demonstrate that pharmacological inhibition of PI3K, TOR, NF-κB, and iNOS increases lifespan of Drosophila without decreasing quality of life. The greatest lifespan expanding effect was achieved by a combination of rapamycin (5 μM) and wortmannin (5 μM) (by 23.4%). The bioinformatic analysis (KEGG, REACTOME.PATH, DOLite, and GO.BP) showed the greatest aging-suppressor activity of rapamycin, consistent with experimental data. PMID:24096697

  20. Molecular evolution of Drosophila metallothionein genes.

    PubMed

    Lange, B W; Langley, C H; Stephan, W

    1990-12-01

    The metallothionein genes of Drosophila melanogaster, Mtn and Mto, may play an important role in heavy metal detoxification. Several different tandem duplications of Mtn have been shown to increase cadmium and copper tolerance, as well as Mtn expression. In order to investigate the possibility of increased selection for duplications of these genes in natural populations exposed to high levels of heavy metals, we compared the frequencies of such duplications among flies collected from metal-contaminated and non-contaminated orchards in Pennsylvania, Tennessee and Georgia. Restriction enzyme analysis was used to screen 1666 wild third chromosomes for Mtn duplications and a subset (327) of these lines for Mto duplications. The frequency of pooled Mtn duplications found ranged from 0% to 20%, and was not significantly higher at the contaminated sites. No Mto duplications were identified. Estimates of sequence diversity at the Mtn locus among a subsample (92) of the duplication survey were obtained using four-cutter analysis. This analysis revealed a low level of polymorphism, consistent with both selection at the Mtn locus, and a fairly recent origin for the duplications. To further examine this hypothesis, we sequenced an Mtn allele of Drosophila simulans and measured the amount of nucleotide sequence divergence between D. simulans and its sibling species D. melanogaster. The levels of silent nucleotide polymorphism and divergence in the Mtn region were compared with those in the Adh region, using the neutrality test of R.R. Hudson, M. Kreitman and M. Aguadé. PMID:1981765

  1. A Drosophila metallophosphoesterase mediates deglycosylation of rhodopsin

    PubMed Central

    Cao, Jinguo; Li, Yi; Xia, Wenjing; Reddig, Keith; Hu, Wen; Xie, Wei; Li, Hong-Sheng; Han, Junhai

    2011-01-01

    Oligosaccharide chains of newly synthesized membrane receptors are trimmed and modified to optimize their trafficking and/or signalling before delivery to the cell surface. For most membrane receptors, the functional significance of oligosaccharide chain modification is unknown. During the maturation of Rh1 rhodopsin, a Drosophila light receptor, the oligosaccharide chain is trimmed extensively. Neither the functional significance of this modification nor the enzymes mediating this process are known. Here, we identify a dmppe (Drosophila metallophosphoesterase) mutant with incomplete deglycosylation of Rh1, and show that the retained oligosaccharide chain does not affect Rh1 localization or signalling. The incomplete deglycosylation, however, renders Rh1 more sensitive to endocytic degradation, and causes morphological and functional defects in photoreceptors of aged dmppe flies. We further demonstrate that the dMPPE protein functions as an Mn2+/Zn2+-dependent phosphoesterase and mediates in vivo dephosphorylation of α-Man-II. Most importantly, the dephosphorylated α-Man-II is required for the removal of the Rh1 oligosaccharide chain. These observations suggest that the glycosylation status of membrane proteins is controlled through phosphorylation/dephosphorylation, and that MPPE acts as the phosphoesterase in this regulation. PMID:21804530

  2. Functional Expression of Drosophila para Sodium Channels

    PubMed Central

    Warmke, Jeffrey W.; Reenan, Robert A.G.; Wang, Peiyi; Qian, Su; Arena, Joseph P.; Wang, Jixin; Wunderler, Denise; Liu, Ken; Kaczorowski, Gregory J.; Ploeg, Lex H.T. Van der; Ganetzky, Barry; Cohen, Charles J.

    1997-01-01

    The Drosophila para sodium channel α subunit was expressed in Xenopus oocytes alone and in combination with tipE, a putative Drosophila sodium channel accessory subunit. Coexpression of tipE with para results in elevated levels of sodium currents and accelerated current decay. Para/TipE sodium channels have biophysical and pharmacological properties similar to those of native channels. However, the pharmacology of these channels differs from that of vertebrate sodium channels: (a) toxin II from Anemonia sulcata, which slows inactivation, binds to Para and some mammalian sodium channels with similar affinity (Kd ≅ 10 nM), but this toxin causes a 100-fold greater decrease in the rate of inactivation of Para/TipE than of mammalian channels; (b) Para sodium channels are >10-fold more sensitive to block by tetrodotoxin; and (c) modification by the pyrethroid insecticide permethrin is >100-fold more potent for Para than for rat brain type IIA sodium channels. Our results suggest that the selective toxicity of pyrethroid insecticides is due at least in part to the greater affinity of pyrethroids for insect sodium channels than for mammalian sodium channels. PMID:9236205

  3. Protein interaction mapping: A Drosophila case study

    PubMed Central

    Formstecher, Etienne; Aresta, Sandra; Collura, Vincent; Hamburger, Alexandre; Meil, Alain; Trehin, Alexandra; Reverdy, Céline; Betin, Virginie; Maire, Sophie; Brun, Christine; Jacq, Bernard; Arpin, Monique; Bellaiche, Yohanns; Bellusci, Saverio; Benaroch, Philippe; Bornens, Michel; Chanet, Roland; Chavrier, Philippe; Delattre, Olivier; Doye, Valérie; Fehon, Richard; Faye, Gérard; Galli, Thierry; Girault, Jean-Antoine; Goud, Bruno; de Gunzburg, Jean; Johannes, Ludger; Junier, Marie-Pierre; Mirouse, Vincent; Mukherjee, Ashim; Papadopoulo, Dora; Perez, Franck; Plessis, Anne; Rossé, Carine; Saule, Simon; Stoppa-Lyonnet, Dominique; Vincent, Alain; White, Michael; Legrain, Pierre; Wojcik, Jérôme; Camonis, Jacques; Daviet, Laurent

    2005-01-01

    The Drosophila (fruit fly) model system has been instrumental in our current understanding of human biology, development, and diseases. Here, we used a high-throughput yeast two-hybrid (Y2H)-based technology to screen 102 bait proteins from Drosophila melanogaster, most of them orthologous to human cancer-related and/or signaling proteins, against high-complexity fly cDNA libraries. More than 2300 protein-protein interactions (PPI) were identified, of which 710 are of high confidence. The computation of a reliability score for each protein-protein interaction and the systematic identification of the interacting domain combined with a prediction of structural/functional motifs allow the elaboration of known complexes and the identification of new ones. The full data set can be visualized using a graphical Web interface, the PIMRider (http://pim.hybrigenics.com), and is also accessible in the PSI standard Molecular Interaction data format. Our fly Protein Interaction Map (PIM) is surprisingly different from the one recently proposed by Giot et al. with little overlap between the two data sets. Analysis of the differences in data sets and methods suggests alternative strategies to enhance the accuracy and comprehensiveness of the post-genomic generation of broad-scale protein interaction maps. PMID:15710747

  4. A tripartite synapse model in Drosophila.

    PubMed

    Danjo, Rie; Kawasaki, Fumiko; Ordway, Richard W

    2011-01-01

    Tripartite (three-part) synapses are defined by physical and functional interactions of glia with pre- and post-synaptic elements. Although tripartite synapses are thought to be of widespread importance in neurological health and disease, we are only beginning to develop an understanding of glial contributions to synaptic function. In contrast to studies of neuronal mechanisms, a significant limitation has been the lack of an invertebrate genetic model system in which conserved mechanisms of tripartite synapse function may be examined through large-scale application of forward genetics and genome-wide genetic tools. Here we report a Drosophila tripartite synapse model which exhibits morphological and functional properties similar to those of mammalian synapses, including glial regulation of extracellular glutamate, synaptically-induced glial calcium transients and glial coupling of synapses with tracheal structures mediating gas exchange. In combination with classical and cell-type specific genetic approaches in Drosophila, this model is expected to provide new insights into the molecular and cellular mechanisms of tripartite synapse function. PMID:21359186

  5. Imaging fictive locomotor patterns in larval Drosophila

    PubMed Central

    Bayley, Timothy G.; Taylor, Adam L.; Berni, Jimena; Bate, Michael; Hedwig, Berthold

    2015-01-01

    We have established a preparation in larval Drosophila to monitor fictive locomotion simultaneously across abdominal and thoracic segments of the isolated CNS with genetically encoded Ca2+ indicators. The Ca2+ signals closely followed spiking activity measured electrophysiologically in nerve roots. Three motor patterns are analyzed. Two comprise waves of Ca2+ signals that progress along the longitudinal body axis in a posterior-to-anterior or anterior-to-posterior direction. These waves had statistically indistinguishable intersegmental phase delays compared with segmental contractions during forward and backward crawling behavior, despite being ∼10 times slower. During these waves, motor neurons of the dorsal longitudinal and transverse muscles were active in the same order as the muscle groups are recruited during crawling behavior. A third fictive motor pattern exhibits a left-right asymmetry across segments and bears similarities with turning behavior in intact larvae, occurring equally frequently and involving asymmetry in the same segments. Ablation of the segments in which forward and backward waves of Ca2+ signals were normally initiated did not eliminate production of Ca2+ waves. When the brain and subesophageal ganglion (SOG) were removed, the remaining ganglia retained the ability to produce both forward and backward waves of motor activity, although the speed and frequency of waves changed. Bilateral asymmetry of activity was reduced when the brain was removed and abolished when the SOG was removed. This work paves the way to studying the neural and genetic underpinnings of segmentally coordinated motor pattern generation in Drosophila with imaging techniques. PMID:26311188

  6. A Drosophila ABC transporter regulates lifespan.

    PubMed

    Huang, He; Lu-Bo, Ying; Haddad, Gabriel G

    2014-12-01

    MRP4 (multidrug resistance-associated protein 4) is a member of the MRP/ABCC subfamily of ATP-binding cassette (ABC) transporters that are essential for many cellular processes requiring the transport of substrates across cell membranes. Although MRP4 has been implicated as a detoxification protein by transport of structurally diverse endogenous and xenobiotic compounds, including antivirus and anticancer drugs, that usually induce oxidative stress in cells, its in vivo biological function remains unknown. In this study, we investigate the biological functions of a Drosophila homolog of human MRP4, dMRP4. We show that dMRP4 expression is elevated in response to oxidative stress (paraquat, hydrogen peroxide and hyperoxia) in Drosophila. Flies lacking dMRP4 have a shortened lifespan under both oxidative and normal conditions. Overexpression of dMRP4, on the other hand, is sufficient to increase oxidative stress resistance and extend lifespan. By genetic manipulations, we demonstrate that dMRP4 is required for JNK (c-Jun NH2-terminal kinase) activation during paraquat challenge and for basal transcription of some JNK target genes under normal condition. We show that impaired JNK signaling is an important cause for major defects associated with dMRP4 mutations, suggesting that dMRP4 regulates lifespan by modulating the expression of a set of genes related to both oxidative resistance and aging, at least in part, through JNK signaling. PMID:25474322

  7. Associations of Yeasts with Spotted-Wing Drosophila (Drosophila suzukii; Diptera: Drosophilidae) in Cherries and Raspberries

    PubMed Central

    Hernández, Alejandro; Zalom, Frank G.

    2012-01-01

    A rich history of investigation documents various Drosophila-yeast mutualisms, suggesting that Drosophila suzukii similarly has an association with a specific yeast species or community. To discover candidate yeast species, yeasts were isolated from larval frass, adult midguts, and fruit hosts of D. suzukii. Terminal restriction fragment length polymorphism (TRFLP) technology and decimal dilution plating were used to identify and determine the relative abundance of yeast species present in fruit juice samples that were either infested with D. suzukii or not infested. Yeasts were less abundant in uninfested than infested samples. A total of 126 independent yeast isolates were cultivated from frass, midguts, and fruit hosts of D. suzukii, representing 28 species of yeasts, with Hanseniaspora uvarum predominating. This suggests an association between D. suzukii and H. uvarum that could be utilized for pest management of the highly pestiferous D. suzukii. PMID:22582060

  8. Associations of yeasts with spotted-wing Drosophila (Drosophila suzukii; Diptera: Drosophilidae) in cherries and raspberries.

    PubMed

    Hamby, Kelly A; Hernández, Alejandro; Boundy-Mills, Kyria; Zalom, Frank G

    2012-07-01

    A rich history of investigation documents various Drosophila-yeast mutualisms, suggesting that Drosophila suzukii similarly has an association with a specific yeast species or community. To discover candidate yeast species, yeasts were isolated from larval frass, adult midguts, and fruit hosts of D. suzukii. Terminal restriction fragment length polymorphism (TRFLP) technology and decimal dilution plating were used to identify and determine the relative abundance of yeast species present in fruit juice samples that were either infested with D. suzukii or not infested. Yeasts were less abundant in uninfested than infested samples. A total of 126 independent yeast isolates were cultivated from frass, midguts, and fruit hosts of D. suzukii, representing 28 species of yeasts, with Hanseniaspora uvarum predominating. This suggests an association between D. suzukii and H. uvarum that could be utilized for pest management of the highly pestiferous D. suzukii. PMID:22582060

  9. Genotoxic effects of cisplatin in somatic tissue of Drosophila melanogaster

    SciTech Connect

    Katz, A.J.

    1987-01-01

    Third instar larvae of Drosophila melanogaster transdihybrid for mwh and flr were exposed to varying concentrations of cisplatin by feeding on dry media wetted with aqueous solutions of the test compound. Larval feeding continued until pupation, and surviving transdihybrid adults were collected seven days following commencement of feeding. Wings of adults were removed and scored under 400X magnification for the presence of twin spots and single spots comprised of clones of cells possessing malformed wing hairs. Cisplatin was found to induce both twin spots and single spots, and significant linear concentration-response relationships were obtained with respect to the induction of all endpoints. This capacity to induce mitotic exchange in the somatic tissue of Drosophila compares well with the compound's reported ability to induce chromosome breaks in Drosophila germ cells. However, not all compounds possess similar genotoxic profiles in the somatic an germ tissue of Drosophila.

  10. Insights From Natural Host-Parasite Interactions: The Drosophila Model

    PubMed Central

    Keebaugh, Erin S.; Schlenke, Todd A.

    2013-01-01

    Immune responses against opportunistic pathogens have been extensively studied in Drosophila, leading to a detailed map of the genetics behind innate immunity networks including the Toll, Imd, Jak-Stat, and JNK pathways. However, immune mechanisms of other organisms, particularly plants, have primarily been investigated using natural pathogens. It was the use of natural pathogens in plant research that revealed the plant R/Avr system, a specialized immune response derived from antagonistic coevolution between plant immune proteins and their natural pathogens’ virulence proteins. Thus, we recommend that researchers begin to use natural Drosophila pathogens to identify novel immune mechanisms that may have arisen through antagonistic coevolution with common natural pathogens. In this review, we address the benefits of using natural pathogens in research, describe the known natural pathogens of Drosophila, and discuss exciting prospects for future research on select natural pathogens of Drosophila. PMID:23764256