Analysis of 6-Pyruvyl Tetrahydropterin Synthase, a Target Gene Product of Su(S) Suppressor in Drosophila.

摘要

Of the 20 suppressor mutants listed in Drosophila, su(s)(sup 2) has been studied for the biochemical characterization of the suppression. In su(s)(sup 2) suppression, some mutants at vermilion (v, 1-33.0), sable (s, 1-43.0), speck (sp, 2-107.0), and purple (pr, 2-54.5) are suppressible by mutants at the suppressor of sable (su(s)) locus. There have been many reports of suppression mechanism studies in purple led to purple loci. The biochemical studies in purple led to in vitro demonstration of a su(s)(sup +) gene product as a negative effector against suppressed purple PPH(sub 4) synthase, which has been also demonstrated in the gene product of vermilion more recently. Both studies led to a proposal for a posttranslational mechanism in which the su(s)(sup +) gene produces a substance that interferes with the function of the target enzymes from the purple and vermilion mutant. In contrast to the transcriptional regulation of the su(s) locus the posttranslational mechanism is based on qualitative differences between wild and suppressed enzyme. Therefore this investigation was to determine if any quantitative or qualitative differences exist between the mutant and wild type target enzymes. 7 refs., 4 figs.