title: Son1p is a component of the 26S proteasome of the yeast Saccharomyces cerevisiae.
abstract: A son1 mutant was isolated as a mutant showing synthetic lethality with nin1-1 which is defective in the p31 component of the regulatory subunit of the yeast 26S proteasome. son1delta showed a synthetic effect with sen3delta and sun1delta, both components of the 26S proteasome, and with cdc28-1N. The 26S proteasome was partially purified from the wild type yeast. The FPLC fractions were analyzed by Western blotting using anti-Son1p antibody and antibodies against some authentic subunits of the 26S proteasome, and we found that Son1p co-migrated with components of the 26S proteasome. The 26S proteasome containing fraction was immunoprecipitated with anti-Son1p antibody. The resultant precipitate contained Nin1p, Sun1p, TBP1, and the 20S proteasome. Combining genetic and biochemical results together, we concluded that Son1p is a component of the yeast 26S proteasome.
authors.affiliation: Department of Biochemistry, Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Fujimuro
authors.forename: K
authors.initials: K
authors.lastname: Tanaka
authors.forename: H
authors.initials: H
authors.lastname: Yokosawa
authors.forename: A
authors.initials: A
authors.lastname: Toh-e
mesh_terms: D015153:Blotting, Western; D005656:Fungal Proteins / Q000235:genetics / Q000302:isolation & purification*; D009154:Mutation; D010447:Peptide Hydrolases / Q000235:genetics / Q000302:isolation & purification*; D046988:Proteasome Endopeptidase Complex; D012441:Saccharomyces cerevisiae / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D010447:Peptide Hydrolases; D046988:Proteasome Endopeptidase Complex; C061553:ATP dependent 26S protease