Identification of cytosolic factors required for nuclear location sequence-mediated binding to the nuclear envelope.
Nuclear protein import can be separated into two distinct steps: binding to the nuclear pore complex followed by translocation to the nuclear interior. A previously identified nuclear location sequence (NLS) receptor and a 97-kD protein purified from bovine erythrocytes reconstitute the binding step in a permeabilized cell assay. Binding to the envelope is specific for a functional SV-40 large T antigen NLS and is not ATP or temperature dependent. Modification of p97 with N-ethylmaleimide (NEM) decreases binding to the pore, but interestingly, NEM treatment of the NLS receptor does not. Nuclear envelope binding is inhibited by wheat germ agglutinin suggesting a possible mechanism for the inhibition of transport by the lectin.
Adam
E J
EJ
Department of Cell, Molecular and Structural Biology, Northwestern University Medical School, Chicago, Illinois 60611.
Adam
S A
SA
D000255:Adenosine Triphosphate / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D001692:Biological Transport; D002417:Cattle; D002451:Cell Compartmentation; D002460:Cell Line; D003600:Cytosol; D005033:Ethylmaleimide / Q000494:pharmacology; D006023:Glycoproteins / Q000378:metabolism; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009685:Nuclear Envelope / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism*; D011485:Protein Binding; D013696:Temperature; D014909:Wheat Germ Agglutinins / Q000494:pharmacology
D006023:Glycoproteins; C075564:NOLC1 protein, human; D009687:Nuclear Proteins; D010455:Peptides; D010750:Phosphoproteins; D014909:Wheat Germ Agglutinins; D000255:Adenosine Triphosphate; D005033:Ethylmaleimide