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Pericentriolar matrix (PCM) integrity relies on cenexin and polo-like kinase (PLK)1.

ABSTRACT: Polo-like-kinase (PLK) 1 activity is associated with maintaining the functional and physical properties of the centrosome's pericentriolar matrix (PCM). In this study, we use a multimodal approach of human cells (HeLa), zebrafish embryos, and phylogenic analysis to test the role of a PLK1 binding protein, cenexin, in regulating the PCM. Our studies identify that cenexin is required for tempering microtubule nucleation by maintaining PCM cohesion in a PLK1-dependent manner. PCM architecture in cenexin-depleted zebrafish embryos was rescued with wild-type human cenexin, but not with a C-terminal cenexin mutant (S796A) deficient in PLK1 binding. We propose a model where cenexin's C terminus acts in a conserved manner in eukaryotes, excluding nematodes and arthropods, to sequester PLK1 that limits PCM substrate phosphorylation events required for PCM cohesion.

SUBMITTER: Aljiboury A

PROVIDER: S-EPMC9582643 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature

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Pericentriolar matrix (PCM) integrity relies on cenexin and polo-like kinase (PLK)1.

Aljiboury Abrar A Mujcic Amra A Curtis Erin E Cammerino Thomas T Magny Denise D Lan Yiling Y Bates Michael M Freshour Judy J Ahmed-Braimeh Yasir H YH Hehnly Heidi H

Molecular biology of the cell 20220524 9

Polo-like-kinase (PLK) 1 activity is associated with maintaining the functional and physical properties of the centrosome's pericentriolar matrix (PCM). In this study, we use a multimodal approach of human cells (HeLa), zebrafish embryos, and phylogenic analysis to test the role of a PLK1 binding protein, cenexin, in regulating the PCM. Our studies identify that cenexin is required for tempering microtubule nucleation by maintaining PCM cohesion in a PLK1-dependent manner. PCM architecture in ce ...[more]

PMID: 35609215

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