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The cortical protein Num1p is essential for dynein-dependent interactions of microtubules with the cortex.

ABSTRACT: In budding yeast, the mitotic spindle moves into the neck between the mother and bud via dynein-dependent sliding of cytoplasmic microtubules along the cortex of the bud. How dynein and microtubules interact with the cortex is unknown. We found that cells lacking Num1p failed to exhibit dynein-dependent microtubule sliding in the bud, resulting in defective mitotic spindle movement and nuclear segregation. Num1p localized to the bud cortex, and that localization was independent of microtubules, dynein, or dynactin. These data are consistent with Num1p being an essential element of the cortical attachment mechanism for dynein-dependent sliding of microtubules in the bud.

SUBMITTER: Heil-Chapdelaine RA

PROVIDER: S-EPMC2190597 | biostudies-literature | 2000 Dec

REPOSITORIES: biostudies-literature

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The cortical protein Num1p is essential for dynein-dependent interactions of microtubules with the cortex.

Heil-Chapdelaine R A RA Oberle J R JR Cooper J A JA

The Journal of cell biology 20001201 6

In budding yeast, the mitotic spindle moves into the neck between the mother and bud via dynein-dependent sliding of cytoplasmic microtubules along the cortex of the bud. How dynein and microtubules interact with the cortex is unknown. We found that cells lacking Num1p failed to exhibit dynein-dependent microtubule sliding in the bud, resulting in defective mitotic spindle movement and nuclear segregation. Num1p localized to the bud cortex, and that localization was independent of microtubules, ...[more]

PMID: 11121446

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