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The CDK subunit CKS2 counteracts CKS1 to control cyclin A/CDK2 activity in maintaining replicative fidelity and neurodevelopment.

ABSTRACT: CKS proteins are evolutionarily conserved cyclin-dependent kinase (CDK) subunits whose functions are incompletely understood. Mammals have two CKS proteins. CKS1 acts as a cofactor to the ubiquitin ligase complex SCF(SKP2) to promote degradation of CDK inhibitors, such as p27. Little is known about the role of the closely related CKS2. Using a Cks2(-/-) knockout mouse model, we show that CKS2 counteracts CKS1 and stabilizes p27. Unopposed CKS1 activity in Cks2(-/-) cells leads to loss of p27. The resulting unrestricted cyclin A/CDK2 activity is accompanied by shortening of the cell cycle, increased replication fork velocity, and DNA damage. In vivo, Cks2(-/-) cortical progenitor cells are limited in their capacity to differentiate into mature neurons, a phenotype akin to animals lacking p27. We propose that the balance between CKS2 and CKS1 modulates p27 degradation, and with it cyclin A/CDK2 activity, to safeguard replicative fidelity and control neuronal differentiation.

SUBMITTER: Frontini M

PROVIDER: S-EPMC3898080 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:Investigation of the roles of CKS1 and CKS2 in murine haematopoiesis.

2024-08-26 | GSE212789 | GEO

The Cks1/Cks2 axis fine-tunes Mll1 expression and is crucial for MLL-rearranged leukaemia cell viability.

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