title: TPD1 of Saccharomyces cerevisiae encodes a protein phosphatase 2C-like activity implicated in tRNA splicing and cell separation.
abstract: The Saccharomyces cerevisiae TPD1 gene has been implicated in tRNA splicing because a tpd1-1 mutant strain accumulates unspliced precursor tRNAs at high temperatures (W. H. van Zyl, N. Wills, and J. R. Broach, Genetics 123:55-68, 1989). The wild-type TPD1 gene was cloned by complementation of the tpd1-1 mutation and shown to encode a protein with substantial homology to protein phosphatase 2C (PP2C) of higher eukaryotes. Expression of Tpd1p in Escherichia coli results in PP2C-like activity. Strains deleted for the TPD1 gene exhibit multiple phenotypes: temperature-sensitive growth, accumulation of unspliced precursor tRNAs, sporulation defects, and failure of cell separation during mitotic growth. On the basis of the presence of these observable phenotypes and the fact that Tpd1p accounts for a small percentage of the observed PP2C activity, we argue that Tpd1p is a unique member of the PP2C family.
authors.affiliation: Department of Biochemistry, University of Rochester Medical School, New York 14642.
authors.forename: M K
authors.initials: MK
authors.lastname: Robinson
authors.forename: W H
authors.initials: WH
authors.lastname: van Zyl
authors.forename: E M
authors.initials: EM
authors.lastname: Phizicky
authors.forename: J R
authors.initials: JR
authors.lastname: Broach
mesh_terms: D000595:Amino Acid Sequence; D002412:Cations / Q000494:pharmacology; D005656:Fungal Proteins / Q000096:biosynthesis* / Q000235:genetics*; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D005838:Genotype; D007700:Kinetics; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000096:biosynthesis* / Q000235:genetics* / Q000378:metabolism; D010957:Plasmids; D054648:Protein Phosphatase 2; D012326:RNA Splicing; D012331:RNA, Fungal / Q000096:biosynthesis; D012362:RNA, Transfer, Ser / Q000096:biosynthesis*; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid
chemical_list: D002412:Cations; D005656:Fungal Proteins; D012331:RNA, Fungal; D012362:RNA, Transfer, Ser; D029701:Saccharomyces cerevisiae Proteins; C087358:PTC1 protein, S cerevisiae; D010749:Phosphoprotein Phosphatases; D054648:Protein Phosphatase 2