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Kinesin molecular motor Eg5 functions during polypeptide synthesis.

ABSTRACT: The kinesin-related molecular motor Eg5 plays roles in cell division, promoting spindle assembly. We show that during interphase Eg5 is associated with ribosomes and is required for optimal nascent polypeptide synthesis. When Eg5 was inhibited, ribosomes no longer bound to microtubules in vitro, ribosome transit rates slowed, and polysomes accumulated in intact cells, suggesting defects in elongation or termination during polypeptide synthesis. These results demonstrate that the molecular motor Eg5 associates with ribosomes and enhances the efficiency of translation.

SUBMITTER: Bartoli KM

PROVIDER: S-EPMC3172266 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Kinesin molecular motor Eg5 functions during polypeptide synthesis.

Bartoli Kristen M KM Jakovljevic Jelena J Woolford John L JL Saunders William S WS

Molecular biology of the cell 20110727 18

The kinesin-related molecular motor Eg5 plays roles in cell division, promoting spindle assembly. We show that during interphase Eg5 is associated with ribosomes and is required for optimal nascent polypeptide synthesis. When Eg5 was inhibited, ribosomes no longer bound to microtubules in vitro, ribosome transit rates slowed, and polysomes accumulated in intact cells, suggesting defects in elongation or termination during polypeptide synthesis. These results demonstrate that the molecular motor ...[more]

PMID: 21795388

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