title: ade9 is an allele of SER1 and plays an indirect role in purine biosynthesis.
abstract: In this study we demonstrate that ade9 plays an indirect role in purine biosynthesis as a non-functional allele of SER1 in Saccharomyces cerevisiae. The SER1 locus, encoding 3-phosphoserine aminotransferase required for serine biosynthesis, is located on chromosome XV and resides approximately where ade9 had previously been mapped genetically. A minimal functional construct of SER1 is necessary and sufficient to complement both the adenine- and serine-requiring phenotypes of ade9 strains. In addition, adequate exogenous serine levels mask the adenine phenotype of ade9. A disruption of SER1 behaves in the same manner phenotypically as the original ade9 strain. Therefore, ade9 can be more accurately described as an allele of SER1.
authors.affiliation: Department of Biology, Georgetown University, Washington, DC 20057-1229, USA.
authors.forename: P S
authors.initials: PS
authors.lastname: Buc
authors.forename: R J
authors.initials: RJ
authors.lastname: Rolfes
mesh_terms: D000483:Alleles; D005561:Formates / Q000494:pharmacology; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal; D009154:Mutation; D011687:Purines / Q000096:biosynthesis*; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D012694:Serine / Q000096:biosynthesis; D000637:Transaminases / Q000235:genetics*
chemical_list: D005561:Formates; D011687:Purines; C030544:formic acid; D012694:Serine; D000637:Transaminases; C022393:phosphoserine aminotransferase