4ga2

Publication Abstract from PubMed

Key steps in mRNA export are the nuclear assembly of messenger ribonucleoprotein particles (mRNPs), the translocation of mRNPs through the nuclear pore complex (NPC), and the mRNP remodeling events at the cytoplasmic side of the NPC. Nup358/RanBP2 is a constituent of the cytoplasmic filaments of the NPC specific to higher eukaryotes and provides a multitude of binding sites for the nucleocytoplasmic transport machinery. Here, we present the crystal structure of the Nup358 N-terminal domain (NTD) at 0.95A resolution. The structure reveals an alpha-helical domain that harbors three central tetratricopeptide repeats (TPRs), flanked on each side by an additional solvating amphipathic alpha helix. Overall, the NTD adopts an unusual extended conformation that lacks the characteristic peptide-binding groove observed in canonical TPR domains. Strikingly, the vast majority of the NTD surface exhibits an evolutionarily conserved, positive electrostatic potential, and we demonstrate that the NTD possesses the capability to bind single-stranded RNA in solution. Together, these data suggest that the NTD contributes to mRNP remodeling events at the cytoplasmic face of the NPC.

Crystal Structure of the N-Terminal Domain of Nup358/RanBP2.,Kassube SA, Stuwe T, Lin DH, Antonuk CD, Napetschnig J, Blobel G, Hoelz A J Mol Biol. 2012 Sep 7. pii: S0022-2836(12)00719-X. doi:, 10.1016/j.jmb.2012.08.026. PMID:22959972^[2]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.