title: NIP1, a gene required for nuclear transport in yeast.
abstract: Cytochrome c with a nuclear localization signal added at the N terminus was mistargeted to the nucleus, resulting in a yeast strain deficient in mitochondrial cytochrome c. Reversion of this strain allowed the isolation of temperature-conditional mutants defective in nuclear transport, as demonstrated with one of these mutants, nip1-1, that was shown to be defective in nuclear accumulation of a LacZ protein containing a nuclear localization signal of the yeast ribosomal protein L29. The NIP1+ gene was cloned and shown to encode a 93,143-Da protein. Furthermore, an epitope-labeled NIP1 protein migrated in SDS/polyacrylamide gels with a mass of approximately 100,000 Da and was shown by immunofluorescence to localize mainly in the cytoplasm. NIP1+ was shown to be an essential gene by gene disruption experiments. Intriguingly, NIP1 has a serine-rich acidic N-terminal region that is similar in this regard to the N-terminal region of a previously described nuclear localization signal-binding protein, NSR1.
authors.affiliation: Department of Biology, University of Rochester, NY 14627.
authors.forename: Z
authors.initials: Z
authors.lastname: Gu
authors.forename: R P
authors.initials: RP
authors.lastname: Moerschell
authors.forename: F
authors.initials: F
authors.lastname: Sherman
authors.forename: D S
authors.initials: DS
authors.lastname: Goldfarb
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D002467:Cell Nucleus / Q000378:metabolism*; D003001:Cloning, Molecular; D003062:Codon / Q000235:genetics; D003574:Cytochrome c Group / Q000235:genetics*; D039621:Eukaryotic Initiation Factor-3; D005656:Fungal Proteins / Q000235:genetics* / Q000302:isolation & purification; D005800:Genes, Fungal; D005816:Genetic Complementation Test; D015151:Immunoblotting; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009687:Nuclear Proteins / Q000235:genetics* / Q000302:isolation & purification; D010641:Phenotype; D014176:Protein Biosynthesis; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D016385:TATA Box; D001616:beta-Galactosidase / Q000235:genetics / Q000302:isolation & purification
chemical_list: D003062:Codon; D003574:Cytochrome c Group; D039621:Eukaryotic Initiation Factor-3; D005656:Fungal Proteins; C077915:NIP1 protein, S cerevisiae; D009687:Nuclear Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D001616:beta-Galactosidase