title: Thr-370 is responsible for CDK11(p58) autophosphorylation, dimerization, and kinase activity.
abstract: CDK11(p58), a member of the p34(cdc2)-related kinase family, is associated with cell cycle progression, tumorigenesis, and proapoptotic signaling. It is also required for the maintenance of chromosome cohesion, the maturation of centrosome, the formation of bipolar spindle, and the completion of mitosis. Here we identified that CDK11(p58) interacted with itself to form homodimers in cells, whereas D224N, the kinase-dead mutant, failed to form homodimers. CDK11(p58) was autophosphorylated, and the main functions of CDK11(p58), such as kinase activity, transactivation of nuclear receptors, and proapoptotic signal transduction, were dependent on its autophosphorylation. Furthermore, the in vitro kinase assay indicated that CDK11(p58) was autophosphorylated at Thr-370. By mutagenesis, we created CDK11(p58) T370A and CDK11(p58) T370D, which mimic the dephosphorylated and phosphorylated forms of CDK11(p58), respectively. The T370A mutant could not form dimers and be phosphorylated by the wild type CDK11(p58) and finally lost the kinase activity. Further functional research revealed that T370A failed to repress the transactivation of androgen receptor and enhance the cell apoptosis. Overall, our data indicated that Thr-370 is responsible for the autophosphorylation, dimerization, and kinase activity of CDK11(p58). Moreover, Thr-370 mutants might affect CDK11(p58)-mediated signaling pathways.
authors.affiliation: Gene Research Center, Shanghai Medical College and Institutes of Biomedical Science, Fudan University, Shanghai 200032, China.
authors.forename: Yayun
authors.initials: Y
authors.lastname: Chi
authors.forename: Chunyi
authors.initials: C
authors.lastname: Zhang
authors.forename: Hongliang
authors.initials: H
authors.lastname: Zong
authors.forename: Yi
authors.initials: Y
authors.lastname: Hong
authors.forename: Xiangfei
authors.initials: X
authors.lastname: Kong
authors.forename: Haiou
authors.initials: H
authors.lastname: Liu
authors.forename: Weiying
authors.initials: W
authors.lastname: Zou
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Wang
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Yun
authors.forename: Jianxin
authors.initials: J
authors.lastname: Gu
mesh_terms: D019943:Amino Acid Substitution; D017209:Apoptosis / Q000502:physiology*; D018844:Cyclin-Dependent Kinases / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D020125:Mutation, Missense; D010766:Phosphorylation / Q000502:physiology; D055503:Protein Multimerization / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D015533:Transcriptional Activation / Q000502:physiology*; D014364:Tryptophan / Q000235:genetics / Q000378:metabolism*
chemical_list: D014364:Tryptophan; C447612:CDK11a protein, human; D018844:Cyclin-Dependent Kinases