Search results for "MELANOGASTER"
showing 10 items of 452 documents
Patterns of Puffing Activity in the Polytene Chromosomes of Drosophila Subobscura
1982
The puffs and Balbiani rings are the visible expression of sites of genetic activity (Beerman, 1952). Since Beermann’s original hypothesis, puffing patterns for several species of Diptera have been described. Thus for the genus Drosophila, Ashburner (1967, 1969a and 1969b) has reported the puffing pattern of Drosophila melanogaster and Drosophila simulans, Beredens (1965) of Drosophila hydei, and Moriwaki and Ito (1969) of Drosophila ananassae. In a previous paper Frutos and Latorre (1981) have determined puffing patterns of the J and U chromosomes of Drosophila subobscura. This species shows a rich chromosomal polymorphism and the puffing pattern of several chromosomal rearrangements of th…
Drosophila adult and larval pheromones modulate larval food choice
2014
Insects use chemosensory cues to feed and mate. In Drosophila , the effect of pheromones has been extensively investigated in adults, but rarely in larvae. The colonization of natural food sources by Drosophila buzzatii and Drosophila simulans species may depend on species-specific chemical cues left in the food by larvae and adults. We identified such chemicals in both species and measured their influence on larval food preference and puparation behaviour. We also tested compounds that varied between these species: (i) two larval volatile compounds: hydroxy-3-butanone-2 and phenol (predominant in D. simulans and D. buzzatii , respectively), and (ii) adult cuticular hydrocarbons (CHs). Dro…
A Protein Nuclear Extract fromD. melanogasterLarval Tissues
2008
Preparation of protein nuclear extracts is often the first step to study in vitro biological processes occurring in the nucleus of the eukaryotic cell. Nuclear extracts have been extensively used in different model organisms to identify and study protein function in nuclei. Drosophila embryos can be collected in large quantities and have been the source of choice for the production of protein nuclear extracts. However, most of Drosophila in vivo studies on protein function are conducted in larval tissues. Here we report a new method to produce highly stable large-scale protein nuclear extracts from whole Drosophila larvae that are suited for a variety of biochemical analyses.
Dysfunction of Torr causes a Harlequin-type ichthyosis-like phenotype in Drosophila melanogaster
2019
AbstractPrevention of desiccation is a constant challenge for terrestrial organisms. Land insects have an extracellular coat, the cuticle, that plays a major role in protection against exaggerated water loss. Here, we report that the ABC transporter Torr - a human ABCA12 paralog - contributes to the waterproof barrier function of the cuticle in the fruit fly Drosophila melanogaster. We show that the reduction or elimination of Torr function provokes rapid desiccation. Torr is also involved in defining the inward barrier against xenobiotics penetration. Consistently, the amounts of cuticular hydrocarbons that are involved in cuticle impermeability decrease markedly when Torr activity is redu…
Developmental speed affects ecological stoichiometry and adult fat reserves in Drosophila melanogaster
2020
Abstract The elemental composition of organisms belongs to a suite of functional traits that change during development in response to environmental conditions. However, associations between adaptive variations in developmental speed and elemental body composition are not well understood. We compared body mass, elemental body composition, food uptake and fat metabolism of Drosophila melanogaster male fruit flies in relation to their larval development speed. Slowly developing flies had higher body carbon concentration than rapidly developing and intermediate flies. Rapidly developing flies had the highest body nitrogen concentration, while slowly developing flies had higher body nitrogen lev…
Labeling of Single Cells in the Central Nervous System of <em>Drosophila melanogaster</em>
2013
In this article we describe how to individually label neurons in the embryonic CNS of Drosophila melanogaster by juxtacellular injection of the lipophilic fluorescent membrane marker DiI. This method allows the visualization of neuronal cell morphology in great detail. It is possible to label any cell in the CNS: cell bodies of target neurons are visualized under DIC optics or by expression of a fluorescent genetic marker such as GFP. After labeling, the DiI can be transformed into a permanent brown stain by photoconversion to allow visualization of cell morphology with transmitted light and DIC optics. Alternatively, the DiI-labeled cells can be observed directly with confocal microscopy, …
Phenobarbital Induction of UDP-glucosyltransferase Activity in Drosophila melanogaster Meigen
2000
The inducibility of UDP-glucosyltransferase activities towards the exogenous substrates 1-naphthol and 2-naphthol and the endogenous metabolite xanthurenic acid was demonstrated in Drosophila melanogaster Meigen larvae and adults using phenobarbital as an inducer. In adults, a 3.5-fold increase of glucosyltransferase activity toward xanthurenic acid and a 2.0-fold increase of the activity toward exogenous substrates (1-naphthol and 2-naphthol) was found. In larvae, maximum induction of all three UDP-glucosyltransferase activities (2.5-fold and 1.5-fold increase of the activity toward the exogenous and endogenous substrates, respectively) was achieved when insects, reared on solid medium, we…
The comparison of beta-thymosin homologues among metazoa supports an arthropod-nematode clade.
2000
The definition of an Ecdysozoa clade among the protostomians, including all phyla with a regularly molted alpha-chitin-rich cuticle, has been one of the most provocative hypotheses to arise from recent investigations on animal phylogeny. Here we present evidence in favor of an arthropod-nematode clade, from the comparison of beta-thymosin homologues among the Metazoa. Arthropods and nematodes share the absence of the highly conserved beta-thymosin form found in all other documented bilaterian phyla as well as sponges, and the possession of a very unusual, internally triplicated homologue of the beta-thymosin protein, unknown in other phyla. We argue that such discrete molecular character is…
Comparative evolution of P–M system and infection by the sigma virus in French and Spanish populations ofDrosophila melanogaster
1992
SummaryIn 1983, an extensive survey of populations ofD. melanogasterwas started in a southern French region (Languedoc) in two non-Mendelian systems: the P–M system of transposable elements and the hereditary Rhabdovirus sigma. Unexpectedly fast-evolving phenomena were observed and interesting correlations were noted, giving similar geographical pattern to the region in both systems. For these reasons, the analysis was continued and extended towards the north (Rhône Valley) and the south (Spain). In the P–M system, all the Languedoc populations evolved from 1983 to 1991 towards the Q type which is characteristic of the Rhône Valley populations. In contrast, M′ strains are currently observed…
Characterization of DrosophilaHemoglobin
2002
In contrast to previous assumptions, the fruit fly Drosophila melanogaster possesses hemoglobin. This respiratory protein forms a monomer of about 17 kDa that is not exported into the hemolymph. Recombinant Drosophila hemoglobin displays a typical hexacoordinated deoxy spectrum and binds oxygen with an affinity of 0.12 torr. Four different hemoglobin transcripts have been identified, which are generated by two distinct promoters of the hemoglobin (glob1) gene but are identical in their coding regions. Putative binding sites for hypoxia-regulated transcription factors have been identified in the gene. Hemoglobin synthesis in Drosophila is mainly associated with the tracheal system and the fa…