title: The nucleoporin-like protein NLP1 (hCG1) promotes CRM1-dependent nuclear protein export.
abstract: Translocation of transport complexes across the nuclear envelope is mediated by nucleoporins, proteins of the nuclear pore complex that contain phenylalanine-glycine (FG) repeats as a characteristic binding motif for transport receptors. CRM1 (exportin 1), the major export receptor, forms trimeric complexes with RanGTP and proteins containing nuclear export sequences (NESs). We analyzed the role of the nucleoporin-like protein 1, NLP1 (also known as hCG1 and NUPL2) in CRM1-dependent nuclear transport. NLP1, which contains many FG repeats, localizes to the nuclear envelope and could also be mobile within the nucleus. It promotes the formation of complexes containing CRM1 and RanGTP, with or without NES-containing cargo proteins, that can be dissociated by RanBP1 and/or the cytoplasmic nucleoporin Nup214. The FG repeats of NLP1 do not play a major role in CRM1 binding. Overexpression of NLP1 promotes CRM1-dependent export of certain cargos, whereas its depletion by small interfering RNAs leads to reduced export rates. Thus, NLP1 functions as an accessory factor in CRM1-dependent nuclear protein export.
authors.affiliation: Department of Biochemistry I, Faculty of Medicine, Georg-August-University of Göttingen, Göttingen, Germany.
authors.forename: Inga
authors.initials: I
authors.lastname: Waldmann
authors.forename: Christiane
authors.initials: C
authors.lastname: Spillner
authors.forename: Ralph H
authors.initials: RH
authors.lastname: Kehlenbach
mesh_terms: D021581:Active Transport, Cell Nucleus; D002467:Cell Nucleus / Q000378:metabolism; D017930:Genes, Reporter; D005998:Glycine / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D028884:Karyopherins / Q000378:metabolism*; D009685:Nuclear Envelope / Q000378:metabolism; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism; D009687:Nuclear Proteins / Q000737:chemistry / Q000378:metabolism*; D029543:Nucleocytoplasmic Transport Proteins / Q000737:chemistry / Q000378:metabolism*; D010649:Phenylalanine / Q000378:metabolism; D011485:Protein Binding; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D020931:ran GTP-Binding Protein / Q000378:metabolism; D000097606:Exportin 1 Protein
chemical_list: D005998:Glycine; D028884:Karyopherins; D028861:Nuclear Pore Complex Proteins; D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; D010649:Phenylalanine; D018160:Receptors, Cytoplasmic and Nuclear; D020931:ran GTP-Binding Protein; D000097606:Exportin 1 Protein; C085914:NUP214 protein, human; C119720:NUP42 protein, human; C120587:RAN protein, human; C091775:ran-binding protein 1