title: Primary structure and disruption of the phosphatidylinositol synthase gene of Saccharomyces cerevisiae.
abstract: The wild-type yeast nuclear gene, PIS, encodes phosphatidylinositol synthase (CDPdiacylglycerol-inositol 3-phosphatidyltransferase, EC 2.7.8.11) (Nikawa, J., and Yamashita, S. (1984) Eur. J. Biochem. 143, 251-256). We now report the sequence of the cloned 2, 129-base pair DNA and the location of the PIS coding region within the sequence. The PIS coding frame is capable of encoding 220 amino acid residues with a calculated molecular weight of 24,823. On Northern blot analysis, an RNA species that hybridized with the coding region was detected in the total poly(A)+ RNA of the wild-type yeast. The primary translation product contains a region showing local sequence homology with yeast phosphatidylserine synthase (EC 2.7.8.8) and Escherichia coli 3-phosphatidyl-1'-glycerol-3'-phosphate synthase (EC 2.7.8.5), suggesting that these three enzymes are evolutionarily related. The PIS gene was disrupted in vitro through insertion of the yeast HIS3 gene into the coding region. A heterozygous diploid, PIS/pis::HIS3, constructed from a PIS/PIS his3/his3 diploid by replacing one of the wild-type PIS genes with the disrupted PIS gene, showed no segregation of viable His+ spores on tetrad analysis, indicating that disruption of the PIS gene is lethal. The nonviable spores were in an arrested state with a characteristic terminal phenotype, suggesting that the function of the PIS gene is essential for progression of the yeast cell cycle.
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D051607:CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase; D004271:DNA, Fungal / Q000235:genetics; D005800:Genes, Fungal; D010770:Phosphotransferases / Q000235:genetics*; D012331:RNA, Fungal / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics*; D017855:Transferases (Other Substituted Phosphate Groups)
chemical_list: D004271:DNA, Fungal; D012331:RNA, Fungal; D012333:RNA, Messenger; D010770:Phosphotransferases; D017855:Transferases (Other Substituted Phosphate Groups); D051607:CDP-Diacylglycerol-Inositol 3-Phosphatidyltransferase