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CENP-V is required for proper chromosome segregation through interaction with spindle microtubules in mouse oocytes

ABSTRACT: Proper chromosome segregation is essential to avoid aneuploidy, yet this process fails with increasing age in mammalian oocytes. Here we report a role for the scarcely described protein CENP-V in oocyte spindle formation and chromosome segregation. We show that depending on the oocyte maturation state, CENP-V localizes to centromeres, to microtubule organizing centers, and to spindle microtubules. We find that Cenp-V−/− oocytes feature severe deficiencies, including metaphase I arrest, strongly reduced polar body extrusion, increased numbers of mis-aligned chromosomes and aneuploidy, multipolar spindles, unfocused spindle poles and loss of kinetochore spindle fibres. We also show that CENP-V protein binds, diffuses along, and bundles microtubules in vitro. The spindle assembly checkpoint arrests about half of metaphase I Cenp-V−/− oocytes from young adults only. This finding suggests checkpoint weakening in ageing oocytes, which mature despite carrying mis-aligned chromosomes. Thus, CENP-V is a microtubule bundling protein crucial to faithful oocyte meiosis, and Cenp-V−/− oocytes reveal age-dependent weakening of the spindle assembly checkpoint. Chromosome segregation is essential to avoid aneuploidy, yet in mammalian oocytes it progressively fails in an age-dependent manner. Here the authors identify CENP-V as a microtubule binding and bundling protein crucial to faithful oocyte meiosis, and present Cenp-V−/− oocytes as revealing age-dependent weakening of the spindle assembly checkpoint.

SUBMITTER: Nabi D

PROVIDER: S-EPMC8586017 | biostudies-literature |

REPOSITORIES: biostudies-literature

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CENP-V is required for proper chromosome segregation through interaction with spindle microtubules in mouse oocytes

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