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RanBP3 influences interactions between CRM1 and its nuclear protein export substrates.

ABSTRACT: We investigated the role of RanBP3, a nuclear member of the Ran-binding protein 1 family, in CRM1-mediated protein export in higher eukaryotes. RanBP3 interacts directly with CRM1 and also forms a trimeric complex with CRM1 and RanGTP. However, RanBP3 does not bind to CRM1 like an export substrate. Instead, it can stabilize CRM1-export substrate interaction. Nuclear RanBP3 stimulates CRM1-dependent protein export in permeabilized cells. These data indicate that RanBP3 functions by a novel mechanism as a cofactor in recognition and export of certain CRM1 substrates. In vitro, RanBP3 binding to CRM1 affects the relative affinity of CRM1 for different substrates.

SUBMITTER: Englmeier L

PROVIDER: S-EPMC1084078 | biostudies-literature | 2001 Oct

REPOSITORIES: biostudies-literature

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RanBP3 influences interactions between CRM1 and its nuclear protein export substrates.

Englmeier L L Fornerod M M Bischoff F R FR Petosa C C Mattaj I W IW Kutay U U

EMBO reports 20010924 10

We investigated the role of RanBP3, a nuclear member of the Ran-binding protein 1 family, in CRM1-mediated protein export in higher eukaryotes. RanBP3 interacts directly with CRM1 and also forms a trimeric complex with CRM1 and RanGTP. However, RanBP3 does not bind to CRM1 like an export substrate. Instead, it can stabilize CRM1-export substrate interaction. Nuclear RanBP3 stimulates CRM1-dependent protein export in permeabilized cells. These data indicate that RanBP3 functions by a novel mechan ...[more]

PMID: 11571268

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