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Flexible gates: dynamic topologies and functions for FG nucleoporins in nucleocytoplasmic transport.

ABSTRACT: The nuclear envelope is a physical barrier between the nucleus and cytoplasm and, as such, separates the mechanisms of transcription from translation. This compartmentalization of eukaryotic cells allows spatial regulation of gene expression; however, it also necessitates a mechanism for transport between the nucleus and cytoplasm. Macromolecular trafficking of protein and RNA occurs exclusively through nuclear pore complexes (NPCs), specialized channels spanning the nuclear envelope. A novel family of NPC proteins, the FG-nucleoporins (FG-Nups), coordinates and potentially regulates NPC translocation. The extensive repeats of phenylalanine-glycine (FG) in each FG-Nup directly bind to shuttling transport receptors moving through the NPC. In addition, FG-Nups are essential components of the nuclear permeability barrier. In this review, we discuss the structural features, cellular functions, and evolutionary conservation of the FG-Nups.

SUBMITTER: Terry LJ

PROVIDER: S-EPMC2794212 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Flexible gates: dynamic topologies and functions for FG nucleoporins in nucleocytoplasmic transport.

Terry Laura J LJ Wente Susan R SR

Eukaryotic cell 20091002 12

The nuclear envelope is a physical barrier between the nucleus and cytoplasm and, as such, separates the mechanisms of transcription from translation. This compartmentalization of eukaryotic cells allows spatial regulation of gene expression; however, it also necessitates a mechanism for transport between the nucleus and cytoplasm. Macromolecular trafficking of protein and RNA occurs exclusively through nuclear pore complexes (NPCs), specialized channels spanning the nuclear envelope. A novel fa ...[more]

PMID: 19801417

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