Human chromosome segregation involves multi-layered regulation of separase by the peptidyl-prolyl-isomerase Pin1.
Mol Cell
; 58(3): 495-506, 2015 May 07.
Article
em En
| MEDLINE
| ID: mdl-25921067
ABSTRACT
Ring-shaped cohesin keeps sister chromatids paired until cleavage of its Scc1/Rad21 subunit by separase triggers chromosome segregation in anaphase. Vertebrate separase is held inactive by mutually exclusive binding to securin or Cdk1-cyclin B1 and becomes unleashed only upon ubiquitin-dependent degradation of these regulators. Although most separase is usually found in association with securin, this anaphase inhibitor is dispensable for murine life while Cdk1-cyclin B1-dependent control of separase is essential. Here, we show that securin-independent inhibition of separase by Cdk1-cyclin B1 in early mitosis requires the phosphorylation-specific peptidyl-prolyl cis/trans isomerase Pin1. Furthermore, isomerization of previously securin-bound separase at the metaphase-to-anaphase transition renders it resistant to re-inhibition by residual securin. At the same time, isomerization also limits the half-life of separase's proteolytic activity, explaining how cohesin can be reloaded onto telophase chromatin in the absence of securin and cyclin B1 without being cleaved.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Regulação Enzimológica da Expressão Gênica
/
Peptidilprolil Isomerase
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Segregação de Cromossomos
/
Separase
Limite:
Humans
Idioma:
En
Revista:
Mol Cell
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Alemanha