Format

Send to

Choose Destination
Cell. 2001 May 18;105(4):459-72.

Phosphorylation of the cohesin subunit Scc1 by Polo/Cdc5 kinase regulates sister chromatid separation in yeast.

Author information

1
Research Institute of Molecular Pathology (IMP), Dr Bohr-Gasse 7, A-1030, Vienna, Austria.

Abstract

At the onset of anaphase, a caspase-related protease (separase) destroys the link between sister chromatids by cleaving the cohesin subunit Scc1. During most of the cell cycle, separase is kept inactive by binding to an inhibitory protein called securin. Separase activation requires proteolysis of securin, which is mediated by an ubiquitin protein ligase called the anaphase-promoting complex. Cells regulate anaphase entry by delaying securin ubiquitination until all chromosomes have attached to the mitotic spindle. Though no longer regulated by this mitotic surveillance mechanism, sister separation remains tightly cell cycle regulated in yeast mutants lacking securin. We show here that the Polo/Cdc5 kinase phosphorylates serine residues adjacent to Scc1 cleavage sites and strongly enhances their cleavage. Phosphorylation of separase recognition sites may be highly conserved and regulates sister chromatid separation independently of securin.

PMID:
11371343
DOI:
10.1016/s0092-8674(01)00362-2
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center