p53 Is Phosphorylatedin Vitroandin Vivoby an Ultraviolet Radiation-induced Protein Kinase Characteristic of the c-Jun Kinase, JNK1

摘要: The p53 tumor suppressor protein is thought to play a major role in the defense of cell against agents that damage DNA. In this report, we describe identification and characterization kinase phosphorylates mouse at single site, serine 34, site phosphorylation cell. activated strikingly following treatment cells with ultraviolet radiation, has native molecular weight approximately 45,000, can be resolved from mitogen-activated (MAP) by chromatography on Superose 6 DEAE-cellulose. activity co-purifies UV-activated c-Jun heparin-Sepharose (but not v-Jun-) affinity column. Treatment partially purified CL100, phosphatase specifically dephosphorylates MAP homologues, inhibits its activity. Taken together, data suggest likely may member stress-activated subfamily kinases. UV irradiation SV3T3 leads increased indicating physiological. Phosphorylation key event signal transduction mechanism coordinately controls nuclear proteins response oxidative stress or DNA damaging agents.