Structural and Functional Characterization of CRM1-Nup214 Interactions Reveals Multiple FG-Binding Sites Involved in Nuclear Export.
CRM1 is the major nuclear export receptor. During translocation through the nuclear pore, transport complexes transiently interact with phenylalanine-glycine (FG) repeats of multiple nucleoporins. On the cytoplasmic side of the nuclear pore, CRM1 tightly interacts with the nucleoporin Nup214. Here, we present the crystal structure of a 117-amino-acid FG-repeat-containing fragment of Nup214, in complex with CRM1, Snurportin 1, and RanGTP at 2.85 Å resolution. The structure reveals eight binding sites for Nup214 FG motifs on CRM1, with intervening stretches that are loosely attached to the transport receptor. Nup214 binds to N- and C-terminal regions of CRM1, thereby clamping CRM1 in a closed conformation and stabilizing the export complex. The role of conserved hydrophobic pockets for the recognition of FG motifs was analyzed in biochemical and cell-based assays. Comparative studies with RanBP3 and Nup62 shed light on specificities of CRM1-nucleoporin binding, which serves as a paradigm for transport receptor-nucleoporin interactions.
Department of Molecular Biology, Faculty of Medicine, GZMB, Georg-August-University Göttingen, Humboldtallee 23, 37073 Göttingen, Germany.
Sarah A
SA
Port
Department of Molecular Structural Biology, Institute for Microbiology and Genetics, GZMB, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany.
Thomas
T
Monecke
Department of Molecular Structural Biology, Institute for Microbiology and Genetics, GZMB, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany.
Achim
A
Dickmanns
Department of Molecular Biology, Faculty of Medicine, GZMB, Georg-August-University Göttingen, Humboldtallee 23, 37073 Göttingen, Germany.
Christiane
C
Spillner
Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany; Bioanalytics, Institute for Clinical Chemistry, University Medical Center, Robert-Koch-Str. 40, 37075 Göttingen, Germany.
Romina
R
Hofele
Bioanalytical Mass Spectrometry Group, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany; Bioanalytics, Institute for Clinical Chemistry, University Medical Center, Robert-Koch-Str. 40, 37075 Göttingen, Germany.
Henning
H
Urlaub
Department of Molecular Structural Biology, Institute for Microbiology and Genetics, GZMB, Georg-August-University Göttingen, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany. Electronic address: rficner@uni-goettingen.de.
Ralf
R
Ficner
Department of Molecular Biology, Faculty of Medicine, GZMB, Georg-August-University Göttingen, Humboldtallee 23, 37073 Göttingen, Germany. Electronic address: rkehlen@gwdg.de.
Ralph H
RH
Kehlenbach
D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000502:physiology*; D001665:Binding Sites / Q000235:genetics / Q000502:physiology; D001692:Biological Transport / Q000235:genetics / Q000502:physiology; D002467:Cell Nucleus / Q000737:chemistry / Q000378:metabolism*; D018360:Crystallography, X-Ray; D006801:Humans; D028884:Karyopherins / Q000737:chemistry / Q000378:metabolism*; D028861:Nuclear Pore Complex Proteins / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D018160:Receptors, Cytoplasmic and Nuclear / Q000737:chemistry / Q000378:metabolism*; D000097606:Exportin 1 Protein
D028884:Karyopherins; D028861:Nuclear Pore Complex Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D000097606:Exportin 1 Protein; C085914:NUP214 protein, human