title: Fission yeast cdc24(+) encodes a novel replication factor required for chromosome integrity.
abstract: A mutation within the Schizosaccharomyces pombe cdc24(+) gene was identified previously in a screen for cell division cycle mutants and the cdc24(+) gene was determined to be essential for S phase in this yeast. We have isolated the cdc24(+) gene by complementation of a new temperature-sensitive allele of the gene, cdc24-G1. The DNA sequence predicts the presence of an open reading frame punctuated by six introns which encodes a pioneer protein of 58 kD. A cdc24 null mutant was generated by homologous recombination. Haploid cells lacking cdc24(+) are inviable, indicating that cdc24(+) is an essential gene. The transcript of cdc24(+) is present at constant levels throughout the cell cycle. Cells lacking cdc24(+) function show a checkpoint-dependent arrest with a 2N DNA content, indicating a block late in S phase. Arrest is accompanied by a rapid loss of viability and chromosome breakage. An S. pombe homolog of the replicative DNA helicase DNA2 of S. cerevisiae suppresses cdc24. These results suggest that Cdc24p plays a role in the progression of normal DNA replication and is required to maintain genomic integrity.
authors.affiliation: Howard Hughes Medical Institute and Department of Cell Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 38232, USA. kathy.gould@mcmail.vanderbilt.edu
authors.forename: K L
authors.initials: KL
authors.lastname: Gould
authors.forename: C G
authors.initials: CG
authors.lastname: Burns
authors.forename: A
authors.initials: A
authors.lastname: Feoktistova
authors.forename: C P
authors.initials: CP
authors.lastname: Hu
authors.forename: S G
authors.initials: SG
authors.lastname: Pasion
authors.forename: S L
authors.initials: SL
authors.lastname: Forsburg
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics; D018797:Cell Cycle Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D002455:Cell Division / Q000235:genetics; D005656:Fungal Proteins / Q000096:biosynthesis / Q000235:genetics; D005816:Genetic Complementation Test; D005838:Genotype; D020662:Guanine Nucleotide Exchange Factors; D007438:Introns; D008969:Molecular Sequence Data; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D011995:Recombination, Genetic; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics; D015183:Restriction Mapping; D029701:Saccharomyces cerevisiae Proteins; D012568:Schizosaccharomyces / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: C073594:CDC24 protein, S cerevisiae; D018797:Cell Cycle Proteins; D005656:Fungal Proteins; D020662:Guanine Nucleotide Exchange Factors; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; D029701:Saccharomyces cerevisiae Proteins