Pyrimidine auxotrophy and the complementation map of the Rudimentary locus of Drosophila melanogaster
β Scribed by Falk, Darrel R.
- Publisher
- Springer
- Year
- 1976
- Tongue
- English
- Weight
- 654 KB
- Volume
- 148
- Category
- Article
- ISSN
- 0026-8925
No coin nor oath required. For personal study only.
β¦ Synopsis
The complementation pattern of twelve rudimentary mutations have been analyzed at two different levels. When analyzed on the basis of complementation for a wing abnormality the mutations can be divided into three groups, each of which is believed to affect the activity of one of the first three enzymes of pyrimidine synthesis (Norby, 1973; Jarry and Falk, 1974; Rawls and Fristrom, 1975). However, when the mutants are analyzed for complementation on the basis of a second phenotype, pyrimidine auxotrophy, the distinction between two of these three groups is not evident. The disparity in the two patterns probably reflects a different threshold of gene activity required for the detection of an auxotrophic phenotype as compared to that at which a wing abnormality is detectable. The biochemical basis of these results is interpreted in light of recent data suggesting that at least the first two enzymes of pyrimidine synthesis are contained within a single multifunctional protein complex (Soderholm et al., 1975).
π SIMILAR VOLUMES
The rudimentary (r) locus of Drosophila melanogaster encodes the first three enzymes for the de novo synthesis of pyrimidines: carbamyl phosphate synthase (CPSase), aspartyl transcarbamylase (ATCase), and dihydroorotase (DHOase). Revertants of leaky r mutants deficient in CPSase have been recovered.
It is shown that the Notch 8 deficiency in Drosophila melanogaster affects a number of enzyme activities localized in the mitochondria, such as NADH oxidase (activity of the complete respiratory chain), NADH dehydrogenase (the first step in the respiratory chain before transfer to ubiquinone), Succi