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Morphologically distinct microtubule ends in the mitotic centrosome of Caenorhabditis elegans.

ABSTRACT: During mitosis, the connections of microtubules (MTs) to centrosomes and kinetochores are dynamic. From in vitro studies, it is known that the dynamic behavior of MTs is related to the structure of their ends, but we know little about the structure of MT ends in spindles. Here, we use high-voltage electron tomography to study the centrosome- and kinetochore-associated ends of spindle MTs in embryonic cells of the nematode, Caenorhabditis elegans. Centrosome-associated MT ends are either closed or open. Closed MT ends are more numerous and are uniformly distributed around the centrosome, but open ends are found preferentially on kinetochore-attached MTs. These results have structural implications for models of MT interactions with centrosomes.

SUBMITTER: O'Toole ET

PROVIDER: S-EPMC2173630 | biostudies-literature | 2003 Nov

REPOSITORIES: biostudies-literature

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Morphologically distinct microtubule ends in the mitotic centrosome of Caenorhabditis elegans.

O'Toole Eileen T ET McDonald Kent L KL Mäntler Jana J McIntosh J Richard JR Hyman Anthony A AA Müller-Reichert Thomas T

The Journal of cell biology 20031101 3

During mitosis, the connections of microtubules (MTs) to centrosomes and kinetochores are dynamic. From in vitro studies, it is known that the dynamic behavior of MTs is related to the structure of their ends, but we know little about the structure of MT ends in spindles. Here, we use high-voltage electron tomography to study the centrosome- and kinetochore-associated ends of spindle MTs in embryonic cells of the nematode, Caenorhabditis elegans. Centrosome-associated MT ends are either closed o ...[more]

PMID: 14610052

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