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Cep57, a multidomain protein with unique microtubule and centrosomal localization domains.

ABSTRACT: The present study demonstrates different functional domains of a recently described centrosomal protein, Cep57 (centrosomal protein 57). Endogenous Cep57 protein and ectopic expression of full-length protein or the N-terminal coiled-coil domain localize to the centrosome internal to gamma-tubulin, suggesting that it is either on both centrioles or on a centromatrix component. The N-terminus can also multimerize with the N-terminus of other Cep57 molecules. The C-terminus contains a second coiled-coil domain that directly binds to MTs (microtubules). This domain both nucleates and bundles MTs in vitro. This activity was also seen in vivo, as overexpression of full-length Cep57 or the C-terminus generates nocodazole-resistant MT cables in cells. Based on the present findings, we propose that Cep57 serves as a link with its N-terminus anchored to the centriole or centromatrix and its C-terminus to MTs.

SUBMITTER: Momotani K

PROVIDER: S-EPMC4351815 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature

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Cep57, a multidomain protein with unique microtubule and centrosomal localization domains.

Momotani Ko K Khromov Alexander S AS Miyake Tsuyoshi T Stukenberg P Todd PT Somlyo Avril V AV

The Biochemical journal 20080601 2

The present study demonstrates different functional domains of a recently described centrosomal protein, Cep57 (centrosomal protein 57). Endogenous Cep57 protein and ectopic expression of full-length protein or the N-terminal coiled-coil domain localize to the centrosome internal to gamma-tubulin, suggesting that it is either on both centrioles or on a centromatrix component. The N-terminus can also multimerize with the N-terminus of other Cep57 molecules. The C-terminus contains a second coiled ...[more]

PMID: 18294141

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