Cdk-mediated phosphorylation of pRB regulates HDAC binding in vitro.
Retinoblastoma protein (pRB) controls the G1/S transition in the cell cycle by binding and inactivating E2F transcription factor. pRB changes the chromatin structure at the E2F-responsive promoter by recruiting histone deacetylase (HDAC) to the pRB-E2F complex, thus controlling the transcriptional activity of E2F. Cyclin-dependent kinases (Cdks) phosphorylate pRB and disrupt association between pRB and E2F. We investigated the effects of pRB phosphorylation on HDAC-1 binding in vitro. Phosphorylation of pRB by Cdk4-cyclin D2, Cdk2-cyclin E, and Cdk2-cyclin A inhibited association of pRB with HDAC. Among these Cdks, Cdk4-cyclin D2 showed particularly effective inhibition of pRB-HDAC complex formation. Using pRB mutants with various deletions in the N- and C-terminal domains, we found that both the pocket and C-terminal domains are important for regulating association between pRB and HDAC.
Banyu Tsukuba Research Institute in collaboration with Merck Research Laboratories, 3 Okubo, Tsukuba, Ibaraki 300-2611, Japan. takakitr@banyu.co.jp
Tohru
T
Takaki
Kazuhiro
K
Fukasawa
Ikuko
I
Suzuki-Takahashi
Hiroshi
H
Hirai
D018797:Cell Cycle Proteins; D018844:Cyclin-Dependent Kinases / Q000378:metabolism* / Q000502:physiology; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D044127:Epigenesis, Genetic; D056284:Histone Deacetylase 1; D006655:Histone Deacetylases / Q000378:metabolism*; D006801:Humans; D010766:Phosphorylation; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016160:Retinoblastoma Protein / Q000737:chemistry / Q000378:metabolism*; D013912:Threonine / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D050684:E2F Transcription Factors; D016160:Retinoblastoma Protein; D014157:Transcription Factors; D013912:Threonine; D018844:Cyclin-Dependent Kinases; C110550:HDAC1 protein, human; D056284:Histone Deacetylase 1; D006655:Histone Deacetylases