title: SCFβ(TrCP) mediates stress-activated MAPK-induced Cdc25B degradation.
abstract: Cdc25A, which is one of the three mammalian CDK-activating Cdc25 protein phosphatases (Cdc25A, B and C), is degraded through SCF(βTrCP)-mediated ubiquitylation following genomic insult; however, the regulation of the stability of the other two Cdc25 proteins is not well understood. Previously, we showed that Cdc25B is primarily degraded by cellular stresses that activate stress-activated MAPKs, such as Jun NH(2)-terminal kinase (JNK) and p38. Here, we report that Cdc25B was ubiquitylated by SCF(βTrCP) E3 ligase upon phosphorylation at two Ser residues in the βTrCP-binding-motif-like sequence D(94)AGLCMDSPSP(104). Point mutation of these Ser residues to alanine (Ala) abolished the JNK-induced ubiquitylation by SCF(βTrCP), and point mutation of DAG to AAG or DAA eradicated both βTrCP binding and ubiquitylation. Further analysis of the mode of βTrCP binding to this region revealed that the PEST-like sequence from E(82)SS to D(94)AG is crucially involved in both the βTrCP binding and ubiquitylation of Cdc25B. Furthermore, the phospho-mimetic replacement of all 10 Ser residues in the E(82)SS to SPSP(104) region with Asp resulted in βTrCP binding. Collectively, these results indicate that stress-induced Cdc25B ubiquitylation by SCF(βTrCP) requires the phosphorylation of S(101)PS(103)P in the βTrCP-binding-motif-like and adjacent PEST-like sequences.
authors.affiliation: Venture Business Laboratory, Center for Innovation, Kanazawa University, Kakuma, Kanazawa 920-1192, Ishikawa, Japan.
authors.forename: Sanae
authors.initials: S
authors.lastname: Uchida
authors.forename: Nobumoto
authors.initials: N
authors.lastname: Watanabe
authors.forename: Yasusei
authors.initials: Y
authors.lastname: Kudo
authors.forename: Katsuji
authors.initials: K
authors.lastname: Yoshioka
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Matsunaga
authors.forename: Yukihito
authors.initials: Y
authors.lastname: Ishizaka
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Nakagama
authors.forename: Randy Y C
authors.initials: RY
authors.lastname: Poon
authors.forename: Katsumi
authors.initials: K
authors.lastname: Yamashita
mesh_terms: D000818:Animals; D004249:DNA Damage; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism*; D006801:Humans; D051379:Mice; D016297:Mutagenesis, Site-Directed; D009154:Mutation / Q000235:genetics; D010766:Phosphorylation / Q000235:genetics; D011485:Protein Binding / Q000235:genetics; D015202:Protein Engineering; D054730:Protein Interaction Domains and Motifs / Q000235:genetics; D054594:Protein Tyrosine Phosphatase, Non-Receptor Type 12 / Q000235:genetics / Q000378:metabolism*; D059748:Proteolysis; D044843:SKP Cullin F-Box Protein Ligases / Q000378:metabolism*; D012694:Serine / Q000235:genetics / Q000378:metabolism; D054875:Ubiquitination / Q000235:genetics; D020687:cdc25 Phosphatases / Q000235:genetics / Q000378:metabolism*
chemical_list: D012694:Serine; D044843:SKP Cullin F-Box Protein Ligases; D048049:Extracellular Signal-Regulated MAP Kinases; D054594:Protein Tyrosine Phosphatase, Non-Receptor Type 12; D020687:cdc25 Phosphatases