title: The type-2 N-end rule peptide recognition activity of Ubr11 ubiquitin ligase is required for the expression of peptide transporters.
abstract: The Ubr1-like canonical N-recognins, widely conserved ubiquitin ligases in eukaryotes, play a role in the N-end rule pathway-mediated degradation of substrates harboring basic (type-1) or bulky hydrophobic (type-2) amino acids at the N-terminus. In this study, the roles of conserved domains were studied in the Schizosaccharomyces pombe Ubr11 protein. Mutations in the UBR box and the autoinhibitory domain blocked degradation of both type-1 and type-2 substrates, expression of peptide transporter genes, and the uptake of oligopeptides. An N-domain mutant was normal for the type-1-related function, but nevertheless failed to express peptide transporters. These data suggest the importance of the type-2-related activity of Ubr11 for its in vivo function.
authors.affiliation: Center for Gene Science, Hiroshima University, Kagamiyama 1-4-2, Higashi-Hiroshima 739-8527, Japan. kkita@hiroshima-u.ac.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Kitamura
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Fujiwara
mesh_terms: D017124:Conserved Sequence; D015870:Gene Expression; D005800:Genes, Fungal; D026901:Membrane Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism; D029702:Schizosaccharomyces pombe Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D044767:Ubiquitin-Protein Ligases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D026901:Membrane Transport Proteins; D011994:Recombinant Proteins; D029702:Schizosaccharomyces pombe Proteins; C043912:peptide permease; D044767:Ubiquitin-Protein Ligases