{"title":"Cells on the move: Modulation of guidance cues during germ cell migration.","authors":"Girish Deshpande, Justinn Barr, Offer Gerlitz, Lyubov Lebedeva, Yulii Shidlovskii, Paul Schedl","doi":"10.1080/19336934.2017.1304332","DOIUrl":"https://doi.org/10.1080/19336934.2017.1304332","url":null,"abstract":"<p><p>In Drosophila melanogaster the progenitors of the germ-line stem cells, the primordial germ cells (PGCs) are formed on the outside surface of the early embryo, while the somatic gonadal precursor cells (SGPs) are specified during mid-embryogenesis. To form the primitive embryonic gonad, the PGCs travel from outside of the embryo, across the mid-gut and then migrate through the mesoderm to the SGPs. The migratory path of PGCs is dictated by a series of attractive and repulsive cues. Studies in our laboratory have shown that one of the key chemoattractants is the Hedgehog (Hh) ligand. Although, Hh is expressed in other cell types, the long-distance transmission of this ligand is specifically potentiated in the SGPs by the hmgcr isoprenoid biosynthetic pathway. The distant transmission of the Hh ligand is gated by restricting expression of hmgcr to the SGPs. This is particularly relevant in light of the recent findings that an ABC transporter, mdr49 also acts in a mesoderm specific manner to release the germ cell attractant. Our studies have demonstrated that mdr49 functions in hh signaling likely via its role in the transport of cholesterol. Given the importance of cholesterol in the processing and long distance transmission of the Hh ligand, this observation has opened up an exciting avenue concerning the possible role of components of the sterol transport machinery in PGC migration.</p>","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 3","pages":"200-207"},"PeriodicalIF":1.2,"publicationDate":"2017-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2017.1304332","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"34817529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-04-03DOI: 10.1080/19336934.2016.1259041
Severine Trannoy, E. Kravitz
{"title":"Strategy changes in subsequent fights as consequences of winning and losing in fruit fly fights","authors":"Severine Trannoy, E. Kravitz","doi":"10.1080/19336934.2016.1259041","DOIUrl":"https://doi.org/10.1080/19336934.2016.1259041","url":null,"abstract":"ABSTRACT In competition for food, territory and mates, male fruit flies (Drosophila melanogaster) engage in agonistic encounters with conspecifics. The fighting strategies used to obtain these resources are influenced by previous and present experience, environmental cues, and the internal state of the animal including hormonal and genetic influences. Animals that experience prior defeats show submissive behavior and are more likely to lose 2nd contests, while animals that win 1st fights are more aggressive and have a higher probability of winning 2nd contests. In a recent report, we examined these loser and winner effects in greater detail and demonstrated that both winners and losers show short-term memory of the results of previous bouts while only losers demonstrate a longer-term memory that requires protein synthesis. The recent findings also suggested that an individual recognition mechanism likely exists that can serve important roles in evaluating the fighting ability of opponents and influencing future fighting strategy. In this article, we follow up on these results by asking how previous defeated and victorious flies change their fighting strategies in the presence of 2nd losing and winning flies, by searching for evidence of territory marking, and discussing the existing literature in light of our findings.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"129 - 138 - 23"},"PeriodicalIF":1.2,"publicationDate":"2017-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2016.1259041","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42903404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-04-03DOI: 10.1080/19336934.2016.1249073
Katarzyna Siudeja, Allison J. Bardin
{"title":"Somatic recombination in adult tissues: What is there to learn?","authors":"Katarzyna Siudeja, Allison J. Bardin","doi":"10.1080/19336934.2016.1249073","DOIUrl":"https://doi.org/10.1080/19336934.2016.1249073","url":null,"abstract":"ABSTRACT Somatic recombination is essential to protect genomes of somatic cells from DNA damage but it also has important clinical implications, as it is a driving force of tumorigenesis leading to inactivation of tumor suppressor genes. Despite this importance, our knowledge about somatic recombination in adult tissues remains very limited. Our recent work, using the Drosophila adult midgut has demonstrated that spontaneous events of mitotic recombination accumulate in aging adult intestinal stem cells and result in frequent loss of heterozygosity (LOH). In this Extra View article, we provide further data supporting long-track chromosome LOH and discuss potential mechanisms involved in the process. In addition, we further discuss relevant questions surrounding somatic recombination and how the mechanisms and factors influencing somatic recombination in adult tissues can be explored using the Drosophila midgut model.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"121 - 128"},"PeriodicalIF":1.2,"publicationDate":"2017-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2016.1249073","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43871159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-04-03Epub Date: 2016-08-19DOI: 10.1080/19336934.2016.1225634
Aleksei S Shatskikh, Yuriy A Abramov, Sergey A Lavrov
{"title":"Trans-inactivation: Repression in a wrong place.","authors":"Aleksei S Shatskikh, Yuriy A Abramov, Sergey A Lavrov","doi":"10.1080/19336934.2016.1225634","DOIUrl":"https://doi.org/10.1080/19336934.2016.1225634","url":null,"abstract":"<p><p>Trans-inactivation is the repression of genes on a normal chromosome under the influence of a rearranged homologous chromosome demonstrating the position effect variegation (PEV). This phenomenon was studied in detail on the example of brown<sup>Dominant</sup> allele causing the repression of wild-type brown gene on the opposite chromosome. We have investigated another trans-inactivation-inducing chromosome rearrangement, In(2)A4 inversion. In both cases, brown<sup>Dominant</sup> and In(2)A4, the repression seems to be the result of dragging of the euchromatic region of the normal chromosome into the heterochromatic environment. It was found that cis-inactivation (classical PEV) and trans-inactivation show different patterns of distribution along the chromosome and respond differently to PEV modifying genes. It appears that the causative mechanism of trans-inactivation is de novo heterochromatin assembly on euchromatic sequences dragged into the heterochromatic nuclear compartment. Trans-inactivation turns out to be the result of a combination of heterochromatin-induced position effect and the somatic interphase chromosome pairing that is widespread in Diptera.</p>","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 2","pages":"96-103"},"PeriodicalIF":1.2,"publicationDate":"2017-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2016.1225634","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"34320349","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-04-03DOI: 10.1080/19336934.2016.1263778
D. Yamamoto, Soh Kohatsu
{"title":"What does the fruitless gene tell us about nature vs. nurture in the sex life of Drosophila?","authors":"D. Yamamoto, Soh Kohatsu","doi":"10.1080/19336934.2016.1263778","DOIUrl":"https://doi.org/10.1080/19336934.2016.1263778","url":null,"abstract":"ABSTRACT The fruitless (fru) gene in Drosophila has been proposed to play a master regulator role in the formation of neural circuitries for male courtship behavior, which is typically considered to be an innate behavior composed of a fixed action pattern as generated by the central pattern generator. However, recent studies have shed light on experience-dependent changes and sensory-input-guided plasticity in courtship behavior. For example, enhanced male-male courtship, a fru mutant “hallmark,” disappears when fru-mutant males are raised in isolation. The fact that neural fru expression is induced by neural activities in the adult invites the supposition that Fru as a chromatin regulator mediates experience-dependent epigenetic modification, which underlies the neural and behavioral plasticity.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"139 - 147"},"PeriodicalIF":1.2,"publicationDate":"2017-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2016.1263778","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47798323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-04-03DOI: 10.1080/19336934.2016.1238993
Allison K Timmons, Albert A Mondragon, Tracy L. Meehan, K. McCall
{"title":"Control of non-apoptotic nurse cell death by engulfment genes in Drosophila","authors":"Allison K Timmons, Albert A Mondragon, Tracy L. Meehan, K. McCall","doi":"10.1080/19336934.2016.1238993","DOIUrl":"https://doi.org/10.1080/19336934.2016.1238993","url":null,"abstract":"ABSTRACT Programmed cell death occurs as a normal part of oocyte development in Drosophila. For each egg that is formed, 15 germline-derived nurse cells transfer their cytoplasmic contents into the oocyte and die. Disruption of apoptosis or autophagy only partially inhibits the death of the nurse cells, indicating that other mechanisms significantly contribute to nurse cell death. Recently, we demonstrated that the surrounding stretch follicle cells non-autonomously promote nurse cell death during late oogenesis and that phagocytosis genes including draper, ced-12, and the JNK pathway are crucial for this process. When phagocytosis genes are inhibited in the follicle cells, events specifically associated with death of the nurse cells are impaired. Death of the nurse cells is not completely blocked in draper mutants, suggesting that other engulfment receptors are involved. Indeed, we found that the integrin subunit, αPS3, is enriched on stretch follicle cells during late oogenesis and is required for elimination of the nurse cells. Moreover, double mutant analysis revealed that integrins act in parallel to draper. Death of nurse cells in the Drosophila ovary is a unique example of programmed cell death that is both non-apoptotic and non-cell autonomously controlled.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"104 - 111 - 55"},"PeriodicalIF":1.2,"publicationDate":"2017-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2016.1238993","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43353624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-02-23DOI: 10.1080/19336934.2017.1291103
Y. Mavromatakis, A. Tomlinson
{"title":"Parsimony and complexity: Cell fate assignment in the developing Drosophila eye","authors":"Y. Mavromatakis, A. Tomlinson","doi":"10.1080/19336934.2017.1291103","DOIUrl":"https://doi.org/10.1080/19336934.2017.1291103","url":null,"abstract":"ABSTRACT The specification of the R7 photoreceptor in the Drosophila eye has become a classic model for understanding how cell fates are assigned in developing systems. R7 is derived from a group of cells that also gives rise to the R1/6 photoreceptor class and the non-photoreceptor cone cells. Our studies examine the signals and cellular information that direct each of these cell types. The cell fates are directed by the combined actions of the Receptor Tyrosine Kinase (RTK) and Notch (N) signaling pathways. The RTK pathway acts to remove the transcription factor Tramtrack (Ttk) which represses the photoreceptor fate. If a cell receives an RTK signal sufficient to remove Ttk then the photoreceptor fate is specified; if not, the cone cell fate results. If Ttk is removed from a cell and its N activity is high then it is specified as an R7, but if its N activity is low then it becomes an R1/6 class photoreceptor. Thus, a remarkably simple molecular code underlies the specification of the fates: 1. Ttk degraded or not: 2. N activity high or low. In the R1/6 and cone cell precursors the molecular codes are achieved with relative simplicity but in the R7 precursor, manifold interactions occur between the RTK and N pathways, and to-date we have identified 4 distinct roles played by N in R7 fate specification. In this review we detail this molecular complexity, and describe how the RTK/N pathway crosstalk eventually leads to the simple molecular code of Tramtrack removed and N activity high. Furthermore, we describe the role played by the transcription factor Lozenge (Lz) in directing retinal precursor fates, and how the RTK/N signals specify different retinal cell types depending on the presence or absence of Lz.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"171 - 178"},"PeriodicalIF":1.2,"publicationDate":"2017-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2017.1291103","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46832024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-02-07DOI: 10.1080/19336934.2017.1283081
T. Miyamoto, H. Amrein
{"title":"Gluconeogenesis: An ancient biochemical pathway with a new twist","authors":"T. Miyamoto, H. Amrein","doi":"10.1080/19336934.2017.1283081","DOIUrl":"https://doi.org/10.1080/19336934.2017.1283081","url":null,"abstract":"ABSTRACT Synthesis of sugars from simple carbon sources is critical for survival of animals under limited nutrient availability. Thus, sugar-synthesizing enzymes should be present across the entire metazoan spectrum. Here, we explore the evolution of glucose and trehalose synthesis using a phylogenetic analysis of enzymes specific for the two pathways. Our analysis reveals that the production of trehalose is the more ancestral biochemical process, found in single cell organisms and primitive metazoans, but also in insects. The gluconeogenic-specific enzyme glucose-6-phosphatase (G6Pase) first appears in Cnidaria, but is also present in Echinodermata, Mollusca and Vertebrata. Intriguingly, some species of nematodes and arthropods possess the genes for both pathways. Moreover, expression data from Drosophila suggests that G6Pase and, hence, gluconeogenesis, initially had a neuronal function. We speculate that in insects—and possibly in some vertebrates—gluconeogenesis may be used as a means of neuronal signaling.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"218 - 223"},"PeriodicalIF":1.2,"publicationDate":"2017-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2017.1283081","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45426693","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-02-06DOI: 10.1080/19336934.2017.1291104
Lorena de Mena, D. Chhangani, P. Fernandez-Funez, D. Rincon-Limas
{"title":"secHsp70 as a tool to approach amyloid-β42 and other extracellular amyloids","authors":"Lorena de Mena, D. Chhangani, P. Fernandez-Funez, D. Rincon-Limas","doi":"10.1080/19336934.2017.1291104","DOIUrl":"https://doi.org/10.1080/19336934.2017.1291104","url":null,"abstract":"ABSTRACT Self-association of amyloidogenic proteins is the main pathological trigger in a wide variety of neurodegenerative disorders. These aggregates are deposited inside or outside the cell due to hereditary mutations, environmental exposures or even normal aging. Cumulative evidence indicates that the heat shock chaperone Hsp70 possesses robust neuroprotection against various intracellular amyloids in Drosophila and mouse models. However, its protective role against extracellular amyloids was largely unknown as its presence outside the cells is very limited. Our recent manuscript in PNAS revealed that an engineered form of secreted Hsp70 (secHsp70) is highly protective against toxicity induced by extracellular deposition of the amyloid-β42 (Aβ42) peptide. In this Extra View article, we extend our analysis to other members of the heat shock protein family. We created PhiC31-based transgenic lines for human Hsp27, Hsp40, Hsp60 and Hsp70 and compared their activities in parallel against extracellular Aβ42. Strikingly, only secreted Hsp70 exhibits robust protection against Aβ42-triggered toxicity in the extracellular milieu. These observations indicate that the ability of secHsp70 to suppress Aβ42 insults is quite unique and suggest that targeted secretion of Hsp70 may represent a new therapeutic approach against Aβ42 and other extracellular amyloids. The potential applications of this engineered chaperone are discussed.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"179 - 184"},"PeriodicalIF":1.2,"publicationDate":"2017-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2017.1291104","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42649161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
FlyPub Date : 2017-01-12DOI: 10.1080/19336934.2016.1270487
A. Manta, Deppie Papadopoulou, A. Polyzos, A. Fragopoulou, A. Skouroliakou, D. Thanos, D. Stravopodis, L. Margaritis
{"title":"Mobile-phone radiation-induced perturbation of gene-expression profiling, redox equilibrium and sporadic-apoptosis control in the ovary of Drosophila melanogaster","authors":"A. Manta, Deppie Papadopoulou, A. Polyzos, A. Fragopoulou, A. Skouroliakou, D. Thanos, D. Stravopodis, L. Margaritis","doi":"10.1080/19336934.2016.1270487","DOIUrl":"https://doi.org/10.1080/19336934.2016.1270487","url":null,"abstract":"ABSTRACT The daily use by people of wireless communication devices has increased exponentially in the last decade, begetting concerns regarding its potential health hazards. Drosophila melanogaster four days-old adult female flies were exposed for 30 min to radiation emitted by a commercial mobile phone at a SAR of 0.15 W/kg and a SAE of 270 J/kg. ROS levels and apoptotic follicles were assayed in parallel with a genome-wide microarrays analysis. ROS cellular contents were found to increase by 1.6-fold (x), immediately after the end of exposure, in follicles of pre-choriogenic stages (germarium - stage 10), while sporadically generated apoptotic follicles (germarium 2b and stages 7–9) presented with an averaged 2x upregulation in their sub-population mass, 4 h after fly's irradiation with mobile device. Microarray analysis revealed 168 genes being differentially expressed, 2 h post-exposure, in response to radiofrequency (RF) electromagnetic field-radiation exposure (≥1.25x, P < 0.05) and associated with multiple and critical biological processes, such as basic metabolism and cellular subroutines related to stress response and apoptotic death. Exposure of adult flies to mobile-phone radiation for 30 min has an immediate impact on ROS production in animal's ovary, which seems to cause a global, systemic and non-targeted transcriptional reprogramming of gene expression, 2 h post-exposure, being finally followed by induction of apoptosis 4 h after the end of exposure. Conclusively, this unique type of pulsed radiation, mainly being derived from daily used mobile phones, seems capable of mobilizing critical cytopathic mechanisms, and altering fundamental genetic programs and networks in D. melanogaster.","PeriodicalId":12128,"journal":{"name":"Fly","volume":"11 1","pages":"75 - 95"},"PeriodicalIF":1.2,"publicationDate":"2017-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/19336934.2016.1270487","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"60065301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}