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ESCRT-III governs the Aurora B-mediated abscission checkpoint through CHMP4C.

ABSTRACT: The endosomal sorting complex required for transport (ESCRT) machinery plays an evolutionarily conserved role in cytokinetic abscission, the final step of cell division where daughter cells are physically separated. Here, we show that charged multivesicular body (MVB) protein 4C (CHMP4C), a human ESCRT-III subunit, is involved in abscission timing. This function correlated with its differential spatiotemporal distribution during late stages of cytokinesis. Accordingly, CHMP4C functioned in the Aurora B-dependent abscission checkpoint to prevent both premature resolution of intercellular chromosome bridges and accumulation of DNA damage. CHMP4C engaged the chromosomal passenger complex (CPC) via interaction with Borealin, which suggested a model whereby CHMP4C inhibits abscission upon phosphorylation by Aurora B. Thus, the ESCRT machinery may protect against genetic damage by coordinating midbody resolution with the abscission checkpoint.

SUBMITTER: Carlton JG

PROVIDER: S-EPMC3998087 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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ESCRT-III governs the Aurora B-mediated abscission checkpoint through CHMP4C.

Carlton Jeremy G JG Caballe Anna A Agromayor Monica M Kloc Magdalena M Martin-Serrano Juan J

Science (New York, N.Y.) 20120315 6078

The endosomal sorting complex required for transport (ESCRT) machinery plays an evolutionarily conserved role in cytokinetic abscission, the final step of cell division where daughter cells are physically separated. Here, we show that charged multivesicular body (MVB) protein 4C (CHMP4C), a human ESCRT-III subunit, is involved in abscission timing. This function correlated with its differential spatiotemporal distribution during late stages of cytokinesis. Accordingly, CHMP4C functioned in the A ...[more]

PMID: 22422861

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