title: Pch1(+), a second essential C-type cyclin gene in Schizosaccharomyces pombe.
abstract: The Schizosaccharomyces pombe gene pch1(+) (pombe cyclin C homology) was isolated in a two-hybrid screen for proteins that interact with Cdc2. The cyclin box region of Pch1 protein shares greatest sequence identity with mammalian and Drosophila C-type cyclins ( approximately 33% identity). Pch1 is significantly less similar to Mcs2 (19% identity), a second member of the C-type cyclin family in S. pombe. Cdc2 co-precipitates with Pch1 in S. pombe cell lysates, although Cdc2 may not be the major catalytic partner of a Pch1 kinase in vivo. Purified Pch1-associated kinase phosphorylated myelin basic protein, histone H1, and a peptide corresponding to the carboxyl-terminal domain repeat of RNA polymerase II. The amount of pch1 mRNA does not oscillate during the cell cycle, as is the case for mRNA transcripts of other C-type cyclin genes. Deltapch1 cells are inviable, therefore S. pombe has two essential genes that encode members of the C-type cyclin family, pch1(+) and mcs2(+). The Deltapch1 mutation causes pleiotropic morphological defects and an associated growth deficiency, but loss of Pch1 activity does not result in a cdc cell cycle-arrest phenotype.
authors.affiliation: Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Furnari
authors.forename: P
authors.initials: P
authors.lastname: Russell
authors.forename: J
authors.initials: J
authors.lastname: Leatherwood
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D056745:Cyclin C; D016213:Cyclins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics*; D017931:DNA Primers; D004331:Drosophila melanogaster; D005800:Genes, Fungal; D006801:Humans; D008322:Mammals; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D055503:Protein Multimerization; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012568:Schizosaccharomyces / Q000235:genetics* / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques
chemical_list: C503674:CCNC protein, human; C503678:CycC protein, Drosophila; D056745:Cyclin C; D016213:Cyclins; D017931:DNA Primers; C105853:Pch1 protein, S pombe; D011994:Recombinant Proteins; D029702:Schizosaccharomyces pombe Proteins