title: Mutations in the homologous ZDS1 and ZDS2 genes affect cell cycle progression.
abstract: The Saccharomyces cerevisiae ZDS1 and ZDS2 genes were identified as multicopy suppressors in distinct genetic screens but were found to encode highly similar proteins. We show that at semipermissive temperatures, a yeast strain with a cdc28-1N allele was uniquely deficient in plasmid maintenance in comparison with strains harboring other cdc28 thermolabile alleles. Quantitative analysis of plasmid loss rates in cdc28-1N strains carrying plasmids with multiple replication origins suggests that a defect in initiating DNA replication probably causes this plasmid loss phenotype. The ZDS1 gene was isolated as a multicopy suppressor of the cdc28-1N plasmid loss defect. A zds1 deletion exhibits genetic interactions with cdc28-1N but not with other cdc28 alleles. SIN4 encodes a protein which is part of the RNA polymerase II holoenzyme-mediator complex, and a sin4 null mutation has pleiotropic effects suggesting roles in transcriptional regulation and chromatin structure. The ZDS2 gene was isolated as a multicopy suppressor of the temperature-sensitive growth defect caused by the sin4 null mutation. Disruption of either ZDS1 or ZDS2 causes only modest phenotypes. However, a strain with both ZDS1 and ZDS2 disrupted is extremely slowly growing, has marked defects in bud morphology, and shows defects in completing S phase or entering mitosis.
authors.affiliation: Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City 84132, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Yu
authors.forename: Y W
authors.initials: YW
authors.lastname: Jiang
authors.forename: R J
authors.initials: RJ
authors.lastname: Wellinger
authors.forename: K
authors.initials: K
authors.lastname: Carlson
authors.forename: J M
authors.initials: JM
authors.lastname: Roberts
authors.forename: D J
authors.initials: DJ
authors.lastname: Stillman
mesh_terms: D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D002453:Cell Cycle / Q000235:genetics*; D005656:Fungal Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D017353:Gene Deletion; D005800:Genes, Fungal; D005804:Genes, Lethal; D016153:Genes, Suppressor; D005838:Genotype; D056892:Mediator Complex; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010641:Phenotype; D016196:S Phase; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000235:genetics / Q000254:growth & development; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D013696:Temperature; D015534:Trans-Activators / Q000096:biosynthesis
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D005656:Fungal Proteins; D056892:Mediator Complex; C076878:SIN4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; C101740:ZDS1 protein, S cerevisiae; C101741:ZDS2 protein, S cerevisiae