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Evidence for anaphase pulling forces during C. elegans meiosis.

ABSTRACT: Anaphase chromosome movement is thought to be mediated by pulling forces generated by end-on attachment of microtubules to the outer face of kinetochores. However, it has been suggested that during C. elegans female meiosis, anaphase is mediated by a kinetochore-independent pushing mechanism with microtubules only attached to the inner face of segregating chromosomes. We found that the kinetochore proteins KNL-1 and KNL-3 are required for preanaphase chromosome stretching, suggesting a role in pulling forces. In the absence of KNL-1,3, pairs of homologous chromosomes did not separate and did not move toward a spindle pole. Instead, each homolog pair moved together with the same spindle pole during anaphase B spindle elongation. Two masses of chromatin thus ended up at opposite spindle poles, giving the appearance of successful anaphase.

SUBMITTER: Danlasky BM

PROVIDER: S-EPMC7577052 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Evidence for anaphase pulling forces during C. elegans meiosis.

Danlasky Brennan M BM Panzica Michelle T MT McNally Karen P KP Vargas Elizabeth E Bailey Cynthia C Li Wenzhe W Gong Ting T Fishman Elizabeth S ES Jiang Xueer X McNally Francis J FJ

The Journal of cell biology 20201201 12

Anaphase chromosome movement is thought to be mediated by pulling forces generated by end-on attachment of microtubules to the outer face of kinetochores. However, it has been suggested that during C. elegans female meiosis, anaphase is mediated by a kinetochore-independent pushing mechanism with microtubules only attached to the inner face of segregating chromosomes. We found that the kinetochore proteins KNL-1 and KNL-3 are required for preanaphase chromosome stretching, suggesting a role in p ...[more]

PMID: 33064834

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