Regulation of CREB-mediated transcription by association of CDK4 binding protein p34SEI-1 with CBP
- Authors: Takuji Hirose, Ryouji Fujii, Hiroshi Nakamura, Satoko Aratani, Hidetoshi Fujita, Minako Nakazawa, Kohzo Nakamura, Kusuki Nishioka, Toshihiro Nakajima
Published online on: Sunday, June 1, 2003
- Pages: 705-712
- DOI: 10.3892/ijmm.11.6.705
CREB binding protein (CBP) plays a central role in cell differentiation and proliferation, interacting with a large number of nuclear factors. To find novel nuclear factors associating with CBP, we have carried out yeast two-hybrid screening of human chondrocyte cDNA library using the C/H3 region of CBP as a bait and cloned CDK4 binding protein p34SEI-1, the recently found cell cycle regulator. The association of p34SEI-1 with CBP was confirmed in vitro by GST pull-down assay and in vivo by coimmunoprecipitation. Results of the immunofluorescence assay also supported the association of p34SEI-1 and CBP. In reporter assay using CRE promoter, p34SEI-1 strongly suppressed CREB-mediated transcription, and this suppression was overcome by excess amount of CBP, but not by CBPΔCH3. It is suggested that the association of p34SEI-1 and CBP is not only involved in cell cycle regulation by CBP, but also have some effect on other CBP-dependent transcription.