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Orc1 controls centriole and centrosome copy number in human cells.

ABSTRACT: Centrosomes, each containing a pair of centrioles, organize microtubules in animal cells, particularly during mitosis. DNA and centrosomes are normally duplicated once before cell division to maintain optimal genome integrity. We report a new role for the Orc1 protein, a subunit of the origin recognition complex (ORC) that is a key component of the DNA replication licensing machinery, in controlling centriole and centrosome copy number in human cells, independent of its role in DNA replication. Cyclin A promotes Orc1 localization to centrosomes where Orc1 prevents Cyclin E-dependent reduplication of both centrioles and centrosomes in a single cell division cycle. The data suggest that Orc1 is a regulator of centriole and centrosome reduplication as well as the initiation of DNA replication.

SUBMITTER: Hemerly AS

PROVIDER: S-EPMC2653626 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Orc1 controls centriole and centrosome copy number in human cells.

Hemerly Adriana S AS Prasanth Supriya G SG Siddiqui Khalid K Stillman Bruce B

Science (New York, N.Y.) 20090201 5915

Centrosomes, each containing a pair of centrioles, organize microtubules in animal cells, particularly during mitosis. DNA and centrosomes are normally duplicated once before cell division to maintain optimal genome integrity. We report a new role for the Orc1 protein, a subunit of the origin recognition complex (ORC) that is a key component of the DNA replication licensing machinery, in controlling centriole and centrosome copy number in human cells, independent of its role in DNA replication. ...[more]

PMID: 19197067

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