title: The NSR1 gene encodes a protein that specifically binds nuclear localization sequences and has two RNA recognition motifs.
abstract: We previously identified a protein (p67) in the yeast, Saccharomyces cerevisiae, that specifically recognizes nuclear localization sequences. We report here the partial purification of p67, and the isolation, sequencing, and disruption of the gene (NSR1) encoding this protein. p67 was purified using an affinity column conjugated with a peptide containing the histone H2B nuclear localization sequence from yeast. Using antibodies against p67 we have cloned the gene for this protein. The protein encoded by the NSR1 gene recognizes the wild-type H2B nuclear localization sequence, but does not recognize a mutant H2B sequence that is incompetent for nuclear localization in vivo. Interestingly, the NSR1 protein has two RNA recognition motifs, as well as an acidic NH2 terminus containing a series of serine clusters, and a basic COOH terminus containing arg-gly repeats. We have confirmed the nuclear localization of p67 by immunofluorescence and found that a restricted portion of the nucleus is highlighted. We have also shown that NSR1 (p67) is required for normal cell growth.
authors.affiliation: Department of Biological Sciences, Columbia University, New York 10027.
authors.forename: W C
authors.initials: WC
authors.lastname: Lee
authors.forename: Z X
authors.initials: ZX
authors.lastname: Xue
authors.forename: T
authors.initials: T
authors.lastname: Mélèse
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification; D002451:Cell Compartmentation; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D004271:DNA, Fungal / Q000235:genetics; D005455:Fluorescent Antibody Technique; D005656:Fungal Proteins / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification / Q000378:metabolism; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009685:Nuclear Envelope / Q000737:chemistry*; D009687:Nuclear Proteins / Q000378:metabolism*; D014176:Protein Biosynthesis; D012313:RNA / Q000378:metabolism; D016601:RNA-Binding Proteins; D011956:Receptors, Cell Surface / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D014158:Transcription, Genetic
chemical_list: D002352:Carrier Proteins; D004271:DNA, Fungal; D005656:Fungal Proteins; C068036:NSR1 protein, S cerevisiae; D009687:Nuclear Proteins; D016601:RNA-Binding Proteins; D011956:Receptors, Cell Surface; D029701:Saccharomyces cerevisiae Proteins; D012313:RNA