title: In vivo and in vitro phosphorylation of the alpha 7/PRS1 subunit of Saccharomyces cerevisiae 20 S proteasome: in vitro phosphorylation by protein kinase CK2 is absolutely dependent on polylysine.
abstract: In this paper, we show that the Saccharomyces cerevisiae 20 S proteasome subunit 1 (PRS1), recently renamed as alpha 7, is the main in vivo phosphorylated and in vitro CK2-phosphorylatable proteasome component. In vitro phosphorylation occurs only in the presence of polylysine, a characteristic that distinguishes the yeast proteasome from mammalian ones which are phosphorylated by CK2 in the absence of polylysine. A peptide reproducing the long acidic C-terminal tail of alpha 7/PRS1, where consensus CK2 phosphorylation sites are located, was also phosphorylated by the CK2 holoenzyme in a polylysine-dependent manner, suggesting that this region contains structural features responsible for this particular behavior.
authors.affiliation: Cátedra de Microbiología, Facultad de Agronomía, Universidad de Buenos Aires, CIBYF (CONICET), Argentina.
authors.forename: P S
authors.initials: PS
authors.lastname: Pardo
authors.forename: P F
authors.initials: PF
authors.lastname: Murray
authors.forename: K
authors.initials: K
authors.lastname: Walz
authors.forename: L
authors.initials: L
authors.lastname: Franco
authors.forename: S
authors.initials: S
authors.lastname: Passeron
mesh_terms: D000595:Amino Acid Sequence; D015153:Blotting, Western; D047390:Casein Kinase II; D003546:Cysteine Endopeptidases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D010446:Peptide Fragments / Q000737:chemistry; D010766:Phosphorylation; D011107:Polylysine / Q000494:pharmacology*; D046988:Proteasome Endopeptidase Complex; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology*
chemical_list: D046911:Macromolecular Substances; D009097:Multienzyme Complexes; D010446:Peptide Fragments; D011994:Recombinant Proteins; D011107:Polylysine; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex