title: Characterization of YDJ1: a yeast homologue of the bacterial dnaJ protein.
abstract: The YDJ1 (yeast dnaJ) gene was isolated from a yeast expression library using antisera made against a yeast nuclear sub-fraction termed the matrix lamina pore complex. The predicted open reading frame displays a 32% identity with the sequence of the Escherichia coli heat shock protein dnaJ. Localization of YDJ1 protein (YDJ1p) by indirect immunofluorescence reveals it to be concentrated in a perinuclear ring as well as in the cytoplasm. YDJ1p cofractionates with nuclei and also microsomes, suggesting that its perinuclear localization reflects association with the ER. YDJ1p is required for normal growth and disruption of its gene results in very slow growing cells that have pleiotropic morphological defects. Haploid cells carrying the disrupted YDJ1 gene are inviable for growth in liquid media. We further show that a related yeast protein, SIS1, is a multicopy suppressor of YDJ1.
authors.affiliation: Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill 27599-7260.
authors.forename: A J
authors.initials: AJ
authors.lastname: Caplan
authors.forename: M G
authors.initials: MG
authors.lastname: Douglas
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D015825:Chromosomes, Fungal; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D005656:Fungal Proteins / Q000235:genetics*; D005798:Genes, Bacterial; D005800:Genes, Fungal; D015698:Genomic Library; D005838:Genotype; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D012689:Sequence Homology, Nucleic Acid
chemical_list: D001426:Bacterial Proteins; C494635:DnaJ protein, E coli; D029968:Escherichia coli Proteins; D005656:Fungal Proteins; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D029701:Saccharomyces cerevisiae Proteins; C070319:YDJ1 protein, S cerevisiae