title: Fission yeast cdc21+ belongs to a family of proteins involved in an early step of chromosome replication.
abstract: The cdc21+ gene of Schizosaccharomyces pombe was originally identified in a screen for cdc mutants affecting S phase and nuclear division. Here we show that the cdc21+ gene product belongs to a family of proteins implicated in DNA replication. These include the Saccharomyces cerevisiae MCM2 and MCM3 proteins, which are needed for the efficient function of certain replication origins, and S.cerevisiae CDC46, which is required for the initiation of chromosome replication. The cdc21 mutant is defective in the mitotic maintenance of some plasmids, like mcm2 and mcm3. The mutant arrests with a single nucleus containing two genome equivalents of DNA, and maintains a cytoplasmic microtubular configuration. Activation of most, but not all, replication origins in the mutant may result in failure to replicate a small proportion of the genome, and this could explain the arrest phenotypes. Using the polymerase chain reaction technique, we have identified new cdc21(+)-related genes in S.cerevisiae, S.pombe and Xenopus laevis. Our results suggest that individual members of the cdc21(+)-related family are highly conserved in evolution.
authors.affiliation: Department of Zoology, University of Oxford, UK.
authors.forename: A
authors.initials: A
authors.lastname: Coxon
authors.forename: K
authors.initials: K
authors.lastname: Maundrell
authors.forename: S E
authors.initials: SE
authors.lastname: Kearsey
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D015825:Chromosomes, Fungal; D003001:Cloning, Molecular; D004261:DNA Replication; D004271:DNA, Fungal / Q000096:biosynthesis; D004268:DNA-Binding Proteins; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism; D005800:Genes, Fungal; D006801:Humans; D064126:Minichromosome Maintenance Complex Component 3; D064148:Minichromosome Maintenance Complex Component 4; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D010641:Phenotype; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D012568:Schizosaccharomyces / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins; D017386:Sequence Homology, Amino Acid; D014714:Vertebrates / Q000235:genetics; D029867:Xenopus Proteins
chemical_list: D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004271:DNA, Fungal; D004268:DNA-Binding Proteins; D005656:Fungal Proteins; C066470:MCM3 protein, human; C069200:MCM5 protein, S cerevisiae; C489423:MCM5 protein, human; D009687:Nuclear Proteins; D029701:Saccharomyces cerevisiae Proteins; D029702:Schizosaccharomyces pombe Proteins; D029867:Xenopus Proteins; C489425:mcm5 protein, Xenopus; C069199:MCM2 protein, S cerevisiae; D064126:Minichromosome Maintenance Complex Component 3; D064148:Minichromosome Maintenance Complex Component 4; C078490:mcm4 protein, S pombe