Open Access mcl1 + , the Schizosaccharomyces pombe Homologue of CTF4 , Is Important for Chromosome Replication, Cohesion, and Segregation
Author(s) -
Dewight Williams,
J. Richard McIntosh
Publication year - 2002
Publication title -
eukaryotic cell
Language(s) - English
Resource type - Journals
eISSN - 1535-9778
pISSN - 1535-9786
DOI - 10.1128/ec.1.5.758-773.2002
Subject(s) - biology , establishment of sister chromatid cohesion , chromosome segregation , schizosaccharomyces , schizosaccharomyces pombe , dna replication , control of chromosome duplication , genetics , mutant , helicase , saccharomyces cerevisiae , homologous recombination , origin recognition complex , sister chromatids , dna , dna repair , chromosome , dna damage , microbiology and biotechnology , eukaryotic dna replication , gene , rna
The fission yeast minichromosome loss mutant mcl1-1 was identified in a screen for mutants defective in chromosome segregation. Missegregation of the chromosomes in mcl1-1 mutant cells results from decreased centromeric cohesion between sister chromatids. mcl1+ encodes a beta-transducin-like protein with similarity to a family of eukaryotic proteins that includes Ctf4p from Saccharomyces cerevisiae, sepB from Aspergillus nidulans, and AND-1 from humans. The previously identified fungal members of this protein family also have chromosome segregation defects, but they primarily affect DNA metabolism. Chromosomes from mcl1-1 cells were heterogeneous in size or structure on pulsed-field electrophoresis gels and had elongated heterogeneous telomeres. mcl1-1 was lethal in combination with the DNA checkpoint mutations rad3delta and rad26delta, demonstrating that loss of Mcl1p function leads to DNA damage. mcl1-1 showed an acute sensitivity to DNA damage that affects S-phase progression. It interacts genetically with replication components and causes an S-phase delay when overexpressed. We propose that Mcl1p, like Ctf4p, has a role in regulating DNA replication complexes.