title: Isolation of an HSP12-homologous gene of Schizosaccharomyces pombe suppressing a temperature-sensitive mutant allele of cdc4.
abstract: Defects in the Schizosaccharomyces pombe (Sp) cell cycle-controlling genes prevent the cell cycle progression. Mutations in one of the late septation genes, cdc4, cause Sp cells to arrest at cytokinesis and result in an elongated cellular morphology. By functional complementation of one of the temperature-sensitive (ts) mutant alleles of cdc4, cdc4-31, with a Sp cDNA library, a novel gene, scf1, which suppresses the elongated ts phenotype of cdc4-31, was isolated. DNA sequence analysis of the cDNA revealed homology with a small heat-shock protein family, HSP12, of Saccharomyces cerevisiae (Sc). Expression of this gene is highly induced, both at 37 degrees C and in the stationary phase of cell growth. It is likely that scf1 is expressed in stress conditions such as heat-shock or nutritional limitation. The phenotypic suppression of cdc4-31 by a small HSP12 homolog, Scf1, suggests that the functional loss of cdc4, which is involved in formation of the F-actin contractile ring, can be prevented or repaired by one of the small HSP. This implies that an HSP might be involved in late cell plate formation or in stabilization of the Sp F-actin contractile ring structure.
authors.affiliation: Biochemistry Laboratory, Korea Research Institute of Bioscience and Biotechnology, KIST, Taejon, Korea.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Jang
authors.forename: S K
authors.initials: SK
authors.lastname: Park
authors.forename: H S
authors.initials: HS
authors.lastname: Yoo
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics*; D003598:Cytoskeletal Proteins; D018076:DNA, Complementary; D044783:F-Box Proteins; D005786:Gene Expression Regulation; D005800:Genes, Fungal; D006360:Heat-Shock Proteins / Q000235:genetics*; D006358:Hot Temperature; D008840:Microfilament Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D012568:Schizosaccharomyces / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins; D013696:Temperature; D044767:Ubiquitin-Protein Ligases
chemical_list: D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D018076:DNA, Complementary; D044783:F-Box Proteins; D006360:Heat-Shock Proteins; D008840:Microfilament Proteins; C099792:Scf1 protein, S pombe; D029702:Schizosaccharomyces pombe Proteins; C115237:actin interacting protein 1; C513274:cdc4 protein, S pombe; D044767:Ubiquitin-Protein Ligases