Content and synthesis of γ-aminobutyric acid in the larval brain ofDrosophila melanogaster

Zusammenfassung Papierchromatographische Untersuchungen an verpuppungsreifen Larven vonDrosophila melanogaster zeigten, dass der relative Gehalt an -Aminobuttersäure im Gehirn rund zweimal höher ist als in der ganzen Larve. Mittels Isotopentechnik wurde eine aktive Synthese der -Aminobuttersäure im Hirnhomogenat nachgewiesen.

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This investigation was supported by grants from the Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung and the Karl-Hescheler-Stiftung.     

The effect of DDT on DNA replication in the larval salivary gland cells ofDrosophila melanogaster

Summary The inhibitory effect of DDT on the initial stage of the DNA replication process in polytene chromosomes of larval salivary gland cells ofDrosophila melanogaster was investigated and possible mechanisms for the inhibition are discussed.     

Kynurenine localization in the egg ofDrosophila melanogaster

Zusammenfassung Papierchromatographische und fluoreszensmikroskopische Untesuchungen von Ovarien der Wildtypen und der Vermilion- und Cinnabar-Mutanten vonDrosophila zeigen, dass sich Kynurenin (der Hauptbestandteil der fluoreszierenden Komponente des Eies) in den proteinhaltigen Dotterschollen des reifenden und des reifen Eies befindet.

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Supported in part by NIH grant No. GM 14891 and a grant from the Research Foundation of the State University of New York.     

Behaviour ofDrosophila melanogaster is affected by drugs

Summary Reserpine, colchicine and Rb⁺ ions exerted specific effects on sexual behaviour and locomotor activity of the fruit fly. Neuroleptics and antidepressants were inactive.     

Superoxide dismutase and life span ofDrosophila melanogaster

Summary Comparison of superoxide dismutase activity in homogenates of wild and vestigial strains ofD. melanogaster revealed a lower enzyme activity in the short-living vestigial strain.Acknowledgments. We are indebted to Prof. M. Olszewska for giving us fly specimens. This work was partly supported by the project No. R. III. 13. 2. 4.     

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.     

Influence of oxygen concentration on development ofDrosophila melanogaster

Summary 1st, 2nd, and early 3rd instarDrosophila larvae are extremely sensitive to 100% O₂ or 75% O₂/25% N₂ (at atmospheric pressure) whereas eggs, late 3rd instar larvae, and pupae are relatively insensitive under our exposure conditions. Eclosing flies exposed to an O₂ enriched environment consistently possessed 2 eye abnormalities: dark eye color and altered eye shape.Supported by NSF-URP grant SP1782684 and a Summer Faculty Fellowship to Harry Nickla.     

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 sex-linked mutantsWhite andBar ofDrosophila melanogaster

Résumé L'observation directe montre qu'il n'y a pas d'isolement sexuel entre le typesauvage (Canton special) et les mutantsBar etwhite deDrosophila melanogaster. L'activité sexuelle des mâles est nettement moindre chezwhite etBar. Par contre les activités locomotrices ne semblent pas inférieures.     

The larval ring gland ofDrosophila melanogaster: A comparison of Ebony and Oregon strains by use of a qualitative protein stain

Résumé Le contenu protéique des cellules glandulaires circulaires des larves de 2 races deDrosophila melanogaster est examiné en détail. Les résultats de cette étude montrent que la production et l'activité hormonale de ces 2 races diffère.     

Xanthine dehydrogenase in the biosynthesis of the eye pterin pigments ofDrosophila melanogaster

Riassunto Il trattamento con HPP di mutanti SE diDrosophila melanogaster ha dato la fenocopia biochimica del doppio mutante MAL/SE (diminuzione della sepiapterina, aumento delle biopterine e, nei maschi, assenza della isoxantopterina con accumulo del precursore 2-amino-4-idrossipterina). Si discute il ruolo dell'enzima XDH nel metabolismo in istudio.

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We are indebted to Wellcome Italia S.p.A., Rome, for a generous gift of HPP (Allopurinol®).