GSBS Student Publications
Title
Possible cross-regulation of phosphate and sulfate metabolism in Saccharomyces cerevisiae
UMMS Affiliation
Graduate School of Biomedical Sciences; Department of Molecular Genetics and Microbiology
Date
9-1-1992
Document Type
Article
Medical Subject Headings
Acid Phosphatase; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; DNA-Binding Proteins; Epistasis, Genetic; Fungal Proteins; Gene Expression Regulation, Fungal; Genes, Suppressor; Genotype; Methionine; Mutation; Phenotype; Phosphates; Plasmids; Saccharomyces cerevisiae; *Saccharomyces cerevisiae Proteins; Sulfates; *Transcription Factors
Disciplines
Life Sciences | Medicine and Health Sciences
Abstract
CP1 (encoded by the gene CEP1) is a sequence-specific DNA binding protein of Saccharomyces cerevisiae that recognizes a sequence element (CDEI) found in both yeast centromeres and gene promoters. Strains lacking CP1 exhibit defects in growth, chromosome segregation and methionine biosynthesis. A YEp24-based yeast genomic library was screened for plasmids which suppressed the methionine auxotrophy of a cep1 null mutant. The suppressing plasmids contained either CEP1 or DNA derived from the PHO4 locus. Subcloning experiments confirmed that suppression correlated with increased dosage of PHO4. PHO4c, pho80 and pho84 mutations, all of which lead to constitutive activation of the PHO4 transcription factor, also suppressed cep1 methionine auxotrophy. The suppression appeared to be a direct effect of PHO4, not a secondary effect of PHO regulon derepression, and was PHO2-dependent. Spontaneously arising extragenic suppressors of cep1 methionine auxotrophy were also isolated; approximately one-third of them were alleles of pho80. While PHO4 overexpression suppressed the methionine auxotrophy of a cep1 mutant, CEP1 overexpression failed to suppress the phenotype of a pho4 mutant; however, a cep1 null mutation suppressed the low inorganic phosphate growth deficiency of a pho84 mutant. The results may suggest that phosphate and sulfate metabolism are cross-regulated.
Rights and Permissions
Citation: Genetics. 1992 Sep;132(1):63-73.
Related Resources
Journal Title
Genetics
PubMed ID
1398064
Repository Citation
O'Connell, Kevin F. and Baker, Richard E., "Possible cross-regulation of phosphate and sulfate metabolism in Saccharomyces cerevisiae" (1992). GSBS Student Publications. 910.
https://escholarship.umassmed.edu/gsbs_sp/910