title: Unloading RNAs in the cytoplasm: an "importin" task.
abstract: The nuclear cap-binding complex (CBC), a heterodimer comprised of a 20 kDa subunit (CBP20) and an 80 kDa regulatory subunit (CBP80), binds to nascent RNA polymerase II transcripts and is important throughout different aspects of RNA metabolism. In a recent publication, using a combination of X-ray crystallographic information, mutagenesis studies, small-angle scattering experiments, analytical ultracentrifugation and in vivo assays, we presented evidence that importin-α and importin-β, two nucleocytoplasmic transport proteins, play key roles in regulating the binding of capped RNA by the CBC in cells. A model for how complexes between CBC and the importins cycle in and out of the nucleus and direct the proper positional binding and release of capped RNA is presented here and is discussed in light of recent publications.
authors.affiliation: Department of Molecular Medicine, College of Veterinary Medicine, Ithaca, NY, USA.
authors.forename: Sandra Mg
authors.initials: SM
authors.lastname: Dias
authors.forename: Richard A
authors.initials: RA
authors.lastname: Cerione
authors.forename: Kristin F
authors.initials: KF
authors.lastname: Wilson
mesh_terms: D000818:Animals; D018360:Crystallography, X-Ray; D003593:Cytoplasm / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D006801:Humans; D028884:Karyopherins / Q000737:chemistry / Q000378:metabolism*; D039502:Nuclear Cap-Binding Protein Complex / Q000378:metabolism; D059370:RNA Folding
chemical_list: D028884:Karyopherins; D039502:Nuclear Cap-Binding Protein Complex