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Phosphate-binding pocket on cyclin B governs CDK substrate phosphorylation and mitotic timing

ABSTRACT: Cell cycle progression is governed by complexes of the cyclin-dependent kinases (CDKs) and their regulatory subunits cyclin and Cks1. CDKs phosphorylate hundreds of substrates, often at multiple sites. Multisite phosphorylation depends on Cks1, which binds initial priming phosphorylation sites to promote secondary phosphorylation at other sites. Here, we describe a similar role for a recently discovered phosphate-binding pocket (PP) on B-type cyclins. Mutation of the PP in Clb2, the major mitotic cyclin of budding yeast, alters bud morphology and delays the onset of anaphase. Mutation of the PP reduces multi-site phosphorylation of CDK substrates in vitro, including the Cdc16 and Cdc27 subunits of the anaphase-promoting complex/cyclosome and the Bud6 and Spa2 subunits of the polarisome. We conclude that the cyclin PP, like Cks1, controls the pattern of multisite phosphorylation on CDK substrates, thereby helping to establish the robust timing of cell-cycle events.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast) Saccharomyces Cerevisiae

SUBMITTER: Robert Maxwell

LAB HEAD: David O. Morgan

PROVIDER: PXD062428 | Pride | 2025-05-19

REPOSITORIES: Pride

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			Action	DRS
	HenryN_Morgan_010925_HCD_HN01.mgf	Mgf
	HenryN_Morgan_010925_HCD_HN01.mzidentml_1_2_0.xml	Mzid
	HenryN_Morgan_010925_HCD_HN01.raw	Raw
	HenryN_Morgan_010925_HCD_HN01_r1.mgf	Mgf
	HenryN_Morgan_010925_HCD_HN01_r1.mzidentml_1_2_0.xml	Mzid

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