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Essential CDK1-inhibitory role for separase during meiosis I in vertebrate oocytes.

ABSTRACT: Separase not only triggers anaphase of meiosis I by proteolytic cleavage of cohesin on chromosome arms, but in vitro vertebrate separase also acts as a direct inhibitor of cyclin-dependent kinase 1 (Cdk1) on liberation from the inhibitory protein, securin. Blocking separase-Cdk1 complex formation by microinjection of anti-separase antibodies prevents polar-body extrusion in vertebrate oocytes. Importantly, proper meiotic maturation is rescued by chemical inhibition of Cdk1 or expression of Cdk1-binding separase fragments lacking cohesin-cleaving activity.

SUBMITTER: Gorr IH

PROVIDER: S-EPMC2435240 | biostudies-literature | 2006 Sep

REPOSITORIES: biostudies-literature

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Essential CDK1-inhibitory role for separase during meiosis I in vertebrate oocytes.

Gorr Ingo H IH Reis Alexandra A Boos Dominik D Wühr Martin M Madgwick Suzanne S Jones Keith T KT Stemmann Olaf O

Nature cell biology 20060813 9

Separase not only triggers anaphase of meiosis I by proteolytic cleavage of cohesin on chromosome arms, but in vitro vertebrate separase also acts as a direct inhibitor of cyclin-dependent kinase 1 (Cdk1) on liberation from the inhibitory protein, securin. Blocking separase-Cdk1 complex formation by microinjection of anti-separase antibodies prevents polar-body extrusion in vertebrate oocytes. Importantly, proper meiotic maturation is rescued by chemical inhibition of Cdk1 or expression of Cdk1- ...[more]

PMID: 16906143

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