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SAC3 may link nuclear protein export to cell cycle progression.

ABSTRACT: Selective movement of proteins between the nucleus and the cytoplasm is a regulatory mechanism exploited extensively by the eukaryotic cell. We have identified the evolutionarily conserved Sac3 protein, which was implicated previously in the regulation of mitosis [Bauer, A. & Kölling, R. (1996) J. Cell Sci. 109, 1575-1583] as a novel mediator of nuclear protein export. We show that Sac3p is localized to the nuclear pore, where it interacts with nucleoporins. Loss of SAC3 function results in a block in nuclear export of a nuclear export signal-containing reporter protein. Our results also demonstrate that SAC3 interacts genetically with the nuclear protein export factors Crm1p/Xpo1p and Yrb2p. Taken together, these data indicate a link between nuclear protein export and transition through the cell cycle.

SUBMITTER: Jones AL

PROVIDER: S-EPMC16220 | biostudies-literature | 2000 Mar

REPOSITORIES: biostudies-literature

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SAC3 may link nuclear protein export to cell cycle progression.

Jones A L AL Quimby B B BB Hood J K JK Ferrigno P P Keshava P H PH Silver P A PA Corbett A H AH

Proceedings of the National Academy of Sciences of the United States of America 20000301 7

Selective movement of proteins between the nucleus and the cytoplasm is a regulatory mechanism exploited extensively by the eukaryotic cell. We have identified the evolutionarily conserved Sac3 protein, which was implicated previously in the regulation of mitosis [Bauer, A. & Kölling, R. (1996) J. Cell Sci. 109, 1575-1583] as a novel mediator of nuclear protein export. We show that Sac3p is localized to the nuclear pore, where it interacts with nucleoporins. Loss of SAC3 function results in a bl ...[more]

PMID: 10716708

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