Genotypic control of mating times inDrosophila melanogaster

Résumé Chez quelques lignées pures et hybrides deDrosophila melanogaster l'accouplement sexuel s'effectue avec des vitesses variables. On peut conclure que la constitution génotypique exerce une action très importante sur la vitesse de l'accouplement.     

Drosophila melanogaster aldehyde dehydrogenase

Summary Subcellular fractionation by differential centrifugation confirms the presence of aldehyde dehydrogenase inD. melanogaster. It is found principally in the heavy mitochondrial fraction.     

Drosophila melanogaster aldehyde dehydrogenase

Subcellular fractionation by differential centrifugation confirms the presence of aldehyde dehydrogenase in D. melanogaster. It is found principally in the heavy mitochondrial fraction.     

Ethanol metabolism in Drosophila melanogaster.

A quantitative study of the transformation of ethanol into acetaldehyde shows that, in Drosophila melanogaster, the mitochondrial ethanol oxidizing system is not very active but that the part played by catalase appears more important than expected. For a strain without alcoholdehydrogenase, ethanol is highly toxic. The presence of acetaldehyde in the culture medium is toxic for all the strains studied. But, since even a strain without any aldehydeoxidase lives normally, the metabolic production of acetaldehyde does not seem dangerous.     

Enzymes of Sphingolipid metabolism in Drosophila melanogaster

Sphingolipids are important structural components of membranes that delimit the boundaries of cellular compartments, cells and organisms. They play an equally important role as second messengers, and transduce signals across or within the compartments they define to initiate physiological changes during development, differentiation and a host of other cellular events. For well over a century Drosophila melanogaster has served as a useful model organism to understand some of the fundamental tenets of development, differentiation and signaling in eukaryotic organisms. Directed approaches to study sphingolipid biology in Drosophila have been initiated only recently. Nevertheless, earlier phenotypic studies conducted on genes of unknown biochemical function have recently been recognized as mutants of enzymes of sphingolipid metabolism. Genome sequencing and annotation have aided the identification of homologs of recently discovered genes. Here we present an overview of studies on enzymes of the de novo sphingolipid biosynthetic pathway, known mutants and their phenotypic characterization in Drosophila.Received 14 June 2004; received after revision 15 August 2004; accepted 21 August 2004     

Toxicity of ouabain on Drosophila melanogaster

Summary Ouabain, also called g-strophantin, is an inhibitor of the Na⁺/K⁺-activated plasma membrane ATPase. Treatment of Drosophila melanogaster with 3–6 mM of this substance leads to a markedly reduced survival of the flies.     

Frequency-dependent mating success among mutant ebony ofDrosophila melanogaster

Summary Measurements of the mating success of wild and ebony strains ofD. melanogaster with different degrees of competition have shown a frequency-dependent effect in both cases, but with a negative correlation for the wild and a positive correlation for the ebony strain.Supported by FAPESP Grant No. 70/049.     

Studies of selective mating using the melanistic mutants ofDrosophila melanogaster

Résumé L'observation directe a montré qu'il n'y a pas d'isolement sexuel entre le typesauvage et les mutants mélaniquesebony etblack deDrosophila melanogaster, mais il existe de notables différences entre l'activité sexuelle et motrice des mâles des trois génotypes. L'importance sélective de ces différences est soulignée.