Search results for "Drosophila Melanogaster"
showing 10 items of 426 documents
Tirant: A new retrotransposon-like element inDrosophila melanogaster
1996
In this paper we report a new retrotransposon-like element of Drosophila melanogaster called Tirant. This sequence is moderately repeated in the genome of this species and it has been found to be widely dispersed throughout its distribution area. From Southern blot and in situ analyses, this sequence appears to be mobile in D. melanogaster, since its chromosome location and the hybridization patterns vary among the different strains analyzed. In this way, partial sequencing of Tirant ends suggests that it is a retrotransposon, since it is flanked by two LTRs. The presence of sequences homologous to Tirant has been also investigated in 28 species of the genus Drosophila by means of Southern …
Spider odors induce stoichiometric changes in fruit fly Drosophila melanogaster
2020
Sequences homologous to the hobo transposable element in E strains of Drosophila melanogaster.
2001
Hobo is one of the three Drosophila melanogaster transposable elements, together with the P and I elements, that seem to have recently invaded the genome of this species. Surveys of the presence of hobo in strains from different geographical and temporal origins have shown that recently collected strains contain complete and deleted elements with high sequence similarity (H strains), but old strains lack hobo elements (E strains). Besides the canonical hobo sequences, both H and E strains show other poorly known hobo-related sequences. In the present work, we analyze the presence, cytogenetic location, and structure of some of these sequences in E strains of D. melanogaster. By in situ hybr…
Spatial discontinuity of Optomotor-blind expression in the Drosophila wing imaginal disc disrupts epithelial architecture and promotes cell sorting
2010
Abstract Background Decapentaplegic (Dpp) is one of the best characterized morphogens, required for dorso-ventral patterning of the Drosophila embryo and for anterior-posterior (A/P) patterning of the wing imaginal disc. In the larval wing pouch, the Dpp target gene optomotor-blind (omb) is generally assumed to be expressed in a step function above a certain threshold of Dpp signaling activity. Results We show that the transcription factor Omb forms, in fact, a symmetrical gradient on both sides of the A/P compartment boundary. Disruptions of the Omb gradient lead to a re-organization of the epithelial cytoskeleton and to a retraction of cells toward the basal membrane suggesting that the O…
Arthropod 7SK RNA
2008
The 7SK small nuclear RNA (snRNA) is a key player in the regulation of polymerase (pol) II transcription. The 7SK RNA was long believed to be specific to vertebrates where it is highly conserved. Homologs in basal deuterostomes and a few lophotrochozoan species were only recently reported. On longer timescales, 7SK evolves rapidly with only few conserved sequence and structure motifs. Previous attempts to identify the Drosophila homolog thus have remained unsuccessful despite considerable efforts. Here we report on the discovery of arthropod 7SK RNAs using a novel search strategy based on pol III promoters, as well as the subsequent verification of its expression. Our results demonstrate th…
Identification of 5,6,7,8-tetrahydropterin and 5,6,7,8-tetrahydrobiopterin in Drosophila melanogaster.
1988
Summary Using reversed-phase high-performance liquid chromatography with electrochemical detection we have demonstrated the occurrence of 5,6,7,8-tetrahydropterin and 5,6,7,8-tetrahydrobiopterin in Drosophila melanogaster . The former is the first time that has been detected in vivo . The identification has been based on the retention times, hydrodinamic voltagrams and the differential concentration in three strains of Drosophila melanogaster . Compared to the wild type, the Punch 2 mutant has diminished levels of both pteridines, whereas Henna-recessive 3 lacks completely tetrahydropterin and has increased levels of tetrahydrobiopterin, as expected according to their biochemical lesions.
Phylogenetic relationships between Drosophila subobscura, D. guanche and D. madeirensis based on Southern analysis of heat shock genes.
2004
A Southern analysis of genomic DNA using Drosophila melanogaster probes for the major heat shock protein genes (Hsp82, Hsp 70, Hsps encoding small proteins) was made to study the phylogenetic relationships between three Drosophila species belonging to the obscura group (D. subobscura, D. guanche, and D. madeirensis). The phylogenetic trees showed that D. madeirensis and D. subobscura are the most closely related species in the triad, while D. guanche is the most distantly related one. As in other Drosophila species, Hsp82 is a single copy gene in D. subobscura, D. guanche, and D. madeirensis, while Hsp 70 and Hsps, which encode small proteins, are genie families. At least four sequences hom…
Flow Cytometry and Karyotype Analysis ofD. melanogasterEye Disc Cells
2008
The developing Drosophila eye-antennal disc is a particularly suited system for the genetic and cellular studies of complex biological processes. Methods to analyze Drosophila eye discs by flow cytometry are mainly based on the dissociation of tissues with trypsin. Dissociation operated by trypsin is very effective, though it causes a lot of stress to live cells often compromising the use of treated cells for further analyses. Here, we report a method to produce dissociated eye-disc cells that retain cell-membrane markers and that can be used for flow cytometry and cytological analysis of mitotic chromosomes. The method described is a great complementing tool for the cellular characterizati…
Analysis of male recombination in third chromosomes of Drosophila melanogaster
1983
Data on male recombination in twenty third-chromosomal lines of Drosophila melanogaster are presented. Frequencies of female and male recombination have been calculated in seven intervals along the third chromosome. The influence on male recombination (M.R.) exercised by different factors such as population origin (cellar, vineyard), the presence of heterozygous inversions and recessive lethal chromosomes, is analyzed. The results obtained lead to the main conclusion that M.R. is not affected by the presence of heterozygous inversions which reduce female recombination in the same lines. In the light of this effect, the possible mechanism operating on male recombination is discussed. Lethal …