Preparing your results

Our searching services are busy right now. Your search will reload in five seconds.

X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

Functional redundancies, distinct localizations and interactions among three fission yeast homologs of centromere protein-B.

Genetics | Mar 12, 2001

http://www.ncbi.nlm.nih.gov/pubmed/11238404

Several members of protein families that are conserved in higher eukaryotes are known to play a role in centromere function in the fission yeast Schizosaccharomyces pombe, including two homologs of the mammalian centromere protein CENP-B, Abp1p and Cbh1p. Here we characterize a third S. pombe CENP-B homolog, Cbh2p (CENP-B homolog 2). cbh2Delta strains exhibited a modest elevation in minichromosome loss, similar to cbh1Delta or abp1Delta strains. cbh2Delta cbh1Delta strains showed little difference in growth or minichromosome loss rate when compared to single deletion strains. In contrast, cbh2Delta abp1Delta strains displayed dramatic morphological and chromosome segregation defects, as well as enhancement of the slow-growth phenotype of abp1Delta strains, indicating partial functional redundancy between these proteins. Both cbh2Delta abp1Delta and cbh1Delta abp1Delta strains also showed strongly enhanced sensitivity to a microtubule-destabilizing drug, consistent with a mitotic function for these proteins. Cbh2p was localized to the central core and core-associated repeat regions of centromeric heterochromatin, but not at several other centromeric and arm locations tested. Thus, like its mammalian counterpart, Cbh2p appeared to be localized exclusively to a portion of centromeric heterochromatin. In contrast, Abp1p was detected in both centromeric heterochromatin and in chromatin at two of three replication origins tested. Cbh2p and Abp1p homodimerized in the budding yeast two-hybrid assay, but did not interact with each other. These results suggest that indirect cooperation between different CENP-B-like DNA binding proteins with partially overlapping chromatin distributions helps to establish a functional centromere.

Pubmed ID: 11238404 RIS Download

Mesh terms: Amino Acid Sequence | Autoantigens | Cell Nucleus | Centromere | Centromere Protein B | Chromatin | Chromosomal Proteins, Non-Histone | Chromosomes | Conserved Sequence | DNA-Binding Proteins | Fungal Proteins | Genes, Fungal | Heterochromatin | Humans | Microtubules | Mitosis | Models, Genetic | Molecular Sequence Data | Mutation | Phenotype | Precipitin Tests | Schizosaccharomyces | Schizosaccharomyces pombe Proteins | Sequence Analysis, DNA | Sequence Homology, Amino Acid | Thiabendazole

Research resources used in this publication

None found

Research tools detected in this publication

None found

Data used in this publication

None found

Associated grants

  • Agency: NIGMS NIH HHS, Id: GM-33783

Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.