Search results for "Drosophila."
showing 10 items of 769 documents
Patterns of puffing activity and chromosomal polymorphism in Drosophila subobscura II. Puffing patterns at the prepupa stage
1985
Puffing activity patterns of the five large polytene chromosomes of Drosophila subobscura were studied during the late third-larval instar and through the prepupal period. A total of 166 loci active in some of the eleven stages studied were described. The distribution of these active loci per chromosome is the following: 25 on chromosome A, 33 on chromosome J, 31 on chromosome U, 34 on chromosome E and 43 on chromosome O. Seven principal patterns of puffing activity were defined taking into account the different curves of the puffing histograms. Gene activities per chromosome as well as total were analysed. Three peaks of gene activity at the beginning, middle and ending of prepupation can …
Differences in gene activity in a Drosophila species cluster belonging to the Obscura group
1993
The polytene chromosome puffing pattern of Drosophila madeirensis was established and compared with those of the related species D. subobscura and D. guanche. A total of 145 loci, active in some of the 12 developmental stages analysed, were described, 38 of which were found to form the puffing pattern characteristic to this species. Taking into account the number of puffs as well as the mean puff expression, D. madeirensis shows a similar activity level to D. guanche, both species being less active than D. subobscura. The low gene activity of D. madeirensis and D. guanche was explained as a consequence of their ecological characteristics.
Taste, movement, and death: varying effects of new prospero mutants during Drosophila development
2003
0022-3034 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; The PGal4 transposon inserted upstream of the pan-neural gene prospero (pros) causes several neural and behavioral defects in the Voila(1) strain. The precise excision of the transposon simultaneously rescued all these defects whereas its unprecise excision created new pros(V) alleles, including the null allele pros(V17). Here, we describe the relationship between the genetic structure of pros locus, larval locomotion, and larval gustatory response. These two behaviors showed varying degrees of variation depending upon the pros allele. We also found a good relation between behavioral alteration, the level …
A stress-responsive miRNA regulates BMP signaling to maintain tissue homeostasis
2021
Adult organisms must sense and adapt to environmental fluctuations. In high-turnover tissues such as the intestine, these adaptive responses require rapid changes in gene expression that, in turn, likely involve posttranscriptional gene control. However, intestinal-tissue-specific microRNA (miRNA)-mediated regulatory pathways remain unexplored. Here, we report the role of an intestinal-specific miRNA, miR-958, that non-cell autonomously regulates stem cell numbers during tissue homeostasis and regeneration in the Drosophila adult midgut. We identify its downstream target cabut, the Drosophila ortholog of mammalian KLF10/11 transcription factors, which mediates this miR-958 function by promo…
TAF-ChIP: an ultra-low input approach for genome-wide chromatin immunoprecipitation assay
2019
The authors present a novel method for obtaining chromatin profiles from low cell numbers without prior nuclei isolation. The method is successfully implemented in generating epigenetic profile from 100 cells with high signal-to-noise ratio.
Data from: Phylogenomics of Lophotrochozoa with consideration of systematic error
2021
Phylogenomic studies have improved understanding of deep metazoan phylogeny and show promise for resolving incongruences among analyses based on limited numbers of loci. One region of the animal tree that has been especially difficult to resolve, even with phylogenomic approaches, is relationships within Lophotrochozoa (the animal clade that includes molluscs, annelids, and flatworms among others). Lack of resolution in phylogenomic analyses could be due to insufficient phylogenetic signal, limitations in taxon and/or gene sampling, or systematic error. Here, we investigated why lophotrochozoan phylogeny has been such a difficult question to answer by identifying and reducing sources of sys…
Data from: Phylogenomics of Lophotrochozoa with consideration of systematic error
2016
Phylogenomic studies have improved understanding of deep metazoan phylogeny and show promise for resolving incongruences among analyses based on limited numbers of loci. One region of the animal tree that has been especially difficult to resolve, even with phylogenomic approaches, is relationships within Lophotrochozoa (the animal clade that includes molluscs, annelids, and flatworms among others). Lack of resolution in phylogenomic analyses could be due to insufficient phylogenetic signal, limitations in taxon and/or gene sampling, or systematic error. Here, we investigated why lophotrochozoan phylogeny has been such a difficult question to answer by identifying and reducing sources of sys…
Cyanide binding and heme cavity conformational transitions in **Drosophila melanogaster** hexacoordinate hemoglobin
2006
The reason for the presence of hemoglobin-like molecules in insects, such as Drosophila melanogaster, that live in fully aerobic environments has yet to be determined. Heme endogenous hexacoordination (where HisE7 and HisF8 axial ligands to the heme Fe atom are both provided by the protein) is a recently discovered mechanism proposed to modulate O-2 affinity in hemoglobins from different species. Previous results have shown that D. melanogaster hemoglobin 1 (product of the glob1 gene) displays heme endogenous hexacoordination in both the ferrous and ferric states. Here we present kinetic data characterizing the exogenous cyanide ligand binding process, and the three-dimensional structure (a…
The hematopoietic niche: a Drosophila model, at last.
2007
The niche provides a specialised microenvironment necessary for maintenance of stem cells in a non differentiated state. While the hematopoietic stem cell (HSC) niche in vertebrates was the first to be recognized, Drosophila niches supporting germline stem cells were characterised first. Recent evidence for the existence of a niche maintaining hematopoietic precursors in Drosophila opens the way to study in vivo the niche/hematopoietic precursors interactions. The availability of a large collection of cell markers, mutants and sophisticated genetic tools makes Drosophila an attractive model for investigating the cellular and molecular mechanisms that are involved in these interactions.
20-Hydroxyecdysone-induced differentiation and apoptosis in the Drosophila cell line, l(2)mbn
2001
20-Hydroxyecdysone has an inhibitory effect on the proliferation of l(2)mbn cells, causes vacuolization and fragmentation of cells, and promotes a strong phagocytotic activity. From several lines of evidence, it can be concluded that 20-hydroxyecdysone induces apoptosis. Long-term video observations following the fate of individual cells, scanning and transmission electron microscopy reveal the typical characteristics of apoptosis: sequestration of small cellular protuberances or larger parts of the cell with nuclear fragments (apoptotic bodies), chromatin condensation, condensation and vesiculation of cytoplasm, whereas the mitochondria retain their normal appearance. The induction of apop…