Functional Association between CBP and HNF4 inTrans-activation

doi:10.1006/bbrc.1997.7871

Biochemical and Biophysical Research Communications

Volume 241, Issue 3, 29 December 1997, Pages 664-669

https://doi.org/10.1006/bbrc.1997.7871 Get rights and content

Abstract

CBP functions as a key transcriptional coactivator for a variety of transcription factors. We show here that the hepatocyte nuclear factor 4 (HNF4), a transcription factor in the nuclear receptor superfamily with no defined ligand, is cloned by yeast two-hybrid system using CBP as a bait. GST-pull down assay with nuclear extracts orin vitrotranslation products revealed that CBP and HNF4 interact with each other at the middle portion (aa 119–375) of HNF4 and two distinct regions (aa 271–451 and 1626–2259) of CBP, respectively, in the ligand-independent manner. Cotransfection experiments indicated that CBP is capable of activating HNF4 site-mediated transcription. These results suggested a functional association between CBP and HNF4 intrans-activation.

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¹: To whom correspondence should be addressed at Institute of Applied Biochemistry, University of Tsukuba, Ibaraki 305, Japan. Fax: 81-298-53-6599. E-mail: [email protected].

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Regular ArticleFunctional Association between CBP and HNF4 inTrans-activation

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Functional Association between CBP and HNF4 inTrans-activation