Nucleic Acids Research Advance Access originally published online on December 26, 2007
Nucleic Acids Research 2008 36(4):1209-1219; doi:10.1093/nar/gkm1131
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Nucleic Acids Research, 2008, Vol. 36, No. 4 1209-1219
© 2007 The Author(s)
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.0/uk/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Molecular Biology |
Proteomic screen defines the hepatocyte nuclear factor 1
-binding partners and identifies HMGB1 as a new cofactor of HNF1
1Beijing Institute of Radiation Medicine, Beijing, 100850, 2Beijing Proteomics Research Center, Beijing, 102206 and 3State Key Laboratory of Proteomics, Beijing, 100850, P. R. China
*To whom correspondence should be addressed. Tel: +86 10 66931424; Fax: +86 10 68212874; Email: xmyang2{at}nic.bmi.ac.cn or xiaomingyang{at}sina.com
Received September 11, 2007. Revised November 28, 2007. Accepted December 5, 2007.
Hepatocyte nuclear factor (HNF)-1
is one of the liver-enriched transcription factors involved in many tissue-specific expressions of hepatic genes. The molecular mechanisms for determining HNF1
-mediated transactivation have not been explained fully. To identify unknown proteins that interact with HNF1
, we developed a co-IP-MS strategy to search HNF1
interactions, and high mobility group protein-B1 (HMGB1), a chromosomal protein, was identified as a novel HNF1
-interacting protein. In vitro glutathione S-transferase pull-down and in vivo co-immunoprecipitation studies confirmed an interaction between HMGB1 and HNF1
. The protein–protein interaction was mediated through the HMG box domains of HMGB1 and the homeodomain of HNF1
. Furthermore, electrophoretic mobility shift assay and chromatin-immunoprecipitation assay demonstrated that HMGB1 was recruited to endogenous HNF1
-responsive promoters and enhanced HNF1
binding to its cognate DNA sequences. Moreover, luciferase reporter analyses showed that HMGB1 potentiated the transcriptional activities of HNF1
in cultured cells, and downregulation of HMGB1 by RNA interference specifically affected the HNF1
-dependent gene expression in HepG2 cell. Taken together, these findings raise the intriguing possibility that HMGB1 is a new cofactor of HNF1
and participates in HNF1
-mediated transcription regulation through protein–protein interaction.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
H.-T. Yu, M. Yu, C.-Y. Li, Y.-Q. Zhan, W.-X. Xu, Y.-H. Li, W. Li, Z.-D. Wang, C.-H. Ge, and X.-M. Yang Specific Expression and Regulation of Hepassocin in the Liver and Down-regulation of the Correlation of HNF1{alpha} with Decreased Levels of Hepassocin in Human Hepatocellular Carcinoma J. Biol. Chem., May 15, 2009; 284(20): 13335 - 13347. [Abstract] [Full Text] [PDF] |
||||
