skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Mechanism of suppression in Drosophila: control of sepiapterin synthase at the purple locus

Journal Article · · Science; (United States)

The amounts of sepiapterin and red pteridine eye pigments (drosopterins) in Drosophila melanogaster are known to be reduced in the purple mutant and restored to normal by a suppressor mutation. We show here that sepiapterin synthase activity is 30% of normal in pr and pr/sup bw/, two naturally occurring alleles of purple, and is restored to nearly normal levels by the suppressor su(s)/sup 2/. A heterozygote of two newly induced alleles of pr has even lower enzyme activity (< 10 percent). The sepiapterin synthase activity is proportional to the number of wild-type pr alleles in flies when one and two copies of the allele are present and is higher in three-than in two-dose flies. We hypothesize that the purple locus may be a structural gene for sepiapterin synthase in Drosophila.

Research Organization:
Oak Ridge National Lab., TN
OSTI ID:
7287088
Journal Information:
Science; (United States), Vol. 198
Country of Publication:
United States
Language:
English