Previous Article | Next Article 
Molecular and Cellular Biology, February 2007, p. 1407-1424, Vol. 27, No. 4
0270-7306/07/$08.00+0 doi:10.1128/MCB.00944-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.
Coordinated Recruitment of Histone Methyltransferase G9a and Other Chromatin-Modifying Enzymes in SHP-Mediated Regulation of Hepatic Bile Acid Metabolism
Sungsoon Fang,1
Ji Miao,2
Lingjin Xiang,1
Bhaskar Ponugoti,1
Eckardt Treuter,3 and
Jongsook Kim Kemper1*
Department of Molecular and Integrative Physiology,1
Department of Cell and Developmental Biology, University of Illinois, Urbana, Illinois 61801,2
Department of Biosciences and Nutrition at Novum, Karolinska Institutet, S-14157 Huddinge, Sweden3
Received 28 May 2006/
Returned for modification 30 June 2006/
Accepted 28 November 2006
SHP has been implicated as a pleiotropic regulator of diverse biological functions by its ability to inhibit numerous nuclear receptors. Recently, we reported that SHP inhibits transcription of CYP7A1, a key gene in bile acid biosynthesis, by recruiting histone deacetylases (HDACs) and a Swi/Snf-Brm complex. To further delineate the mechanism of this inhibition, we have examined whether methylation of histones is also involved and whether a functional interplay between chromatin-modifying enzymes occurs. The histone methyltransferase G9a, but not SUV39, was colocalized with SHP in the nucleus and directly interacted with SHP in vitro. G9a, which was coimmunoprecipitated with hepatic SHP, methylated Lys-9 of histone 3 (H3K9) in vitro. Expression of G9a enhanced inhibition of CYP7A1 transcription by SHP, while a catalytically inactive G9a dominant negative (DN) mutant reversed the SHP inhibition. G9a was recruited to and H3K9 was methylated at the CYP7A1 promoter in a SHP-dependent manner in bile acid-treated HepG2 cells. Expression of the G9a-DN mutant inhibited H3K9 methylation, blocked the recruitment of the Brm complex, and partially reversed CYP7A1 inhibition by bile acids. Inhibition of HDAC activity with trichostatin A blocked deacetylation and methylation of H3K9 at the promoter, and, conversely, inhibition of H3K9 methylation by G9a-DN partially blocked deacetylation. Hepatic expression of G9a-DN in mice fed cholic acid disrupted bile acid homeostasis, resulting in increased bile acid pools and partial de-repression of Cyp7a1 and Cyp8b1. Our studies establish a critical role for G9a methyltransferase, histone deacetylases, and the Swi/Snf-Brm complex in the SHP-mediated inhibition of hepatic bile acid synthesis via coordinated chromatin modification at target genes.
* Corresponding author. Mailing address: Department of Molecular and Integrative Physiology, University of Illinois, Urbana, IL 61801. Phone: (217) 333-6317. Fax: (217) 333-1133. E-mail:
jongsook{at}uiuc.edu.
Published ahead of print on 4 December 2006.
Molecular and Cellular Biology, February 2007, p. 1407-1424, Vol. 27, No. 4
0270-7306/07/$08.00+0 doi:10.1128/MCB.00944-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.
This article has been cited by other articles:
-
Miao, J., Fang, S., Lee, J., Comstock, C., Knudsen, K. E., Kemper, J. K.
(2009). Functional Specificities of Brm and Brg-1 Swi/Snf ATPases in the Feedback Regulation of Hepatic Bile Acid Biosynthesis. Mol. Cell. Biol.
29: 6170-6181
[Abstract]
[Full Text]
-
Chiang, J. Y. L.
(2009). Bile acids: regulation of synthesis. J. Lipid Res.
50: 1955-1966
[Abstract]
[Full Text]
-
Farhana, L., Dawson, M. I., Xu, L., Dannenberg, J.-H., Fontana, J. A.
(2009). SHP and Sin3A expression are essential for adamantyl-substituted retinoid-related molecule-mediated nuclear factor-{kappa}B activation, c-Fos/c-Jun expression, and cellular apoptosis. Molecular Cancer Therapeutics
8: 1625-1635
[Abstract]
[Full Text]
-
Shin, D.-J., Osborne, T. F.
(2009). FGF15/FGFR4 Integrates Growth Factor Signaling with Hepatic Bile Acid Metabolism and Insulin Action. J. Biol. Chem.
284: 11110-11120
[Abstract]
[Full Text]
-
Miao, J., Xiao, Z., Kanamaluru, D., Min, G., Yau, P. M., Veenstra, T. D., Ellis, E., Strom, S., Suino-Powell, K., Xu, H. E., Kemper, J. K.
(2009). Bile acid signaling pathways increase stability of Small Heterodimer Partner (SHP) by inhibiting ubiquitin-proteasomal degradation. Genes Dev.
23: 986-996
[Abstract]
[Full Text]
-
Kim, J. K., Esteve, P.-O., Jacobsen, S. E., Pradhan, S.
(2009). UHRF1 binds G9a and participates in p21 transcriptional regulation in mammalian cells. Nucleic Acids Res
37: 493-505
[Abstract]
[Full Text]
-
Fang, S., Tsang, S., Jones, R., Ponugoti, B., Yoon, H., Wu, S.-Y., Chiang, C.-M., Willson, T. M., Kemper, J. K.
(2008). The p300 Acetylase Is Critical for Ligand-activated Farnesoid X Receptor (FXR) Induction of SHP. J. Biol. Chem.
283: 35086-35095
[Abstract]
[Full Text]
-
Shin, D.-J., Osborne, T. F.
(2008). Peroxisome Proliferator-activated Receptor-{gamma} Coactivator-1{alpha} Activation of CYP7A1 during Food Restriction and Diabetes Is Still Inhibited by Small Heterodimer Partner. J. Biol. Chem.
283: 15089-15096
[Abstract]
[Full Text]
-
Ponugoti, B., Fang, S., Kemper, J. K.
(2007). Functional Interaction of Hepatic Nuclear Factor-4 and Peroxisome Proliferator-Activated Receptor-{gamma} Coactivator 1{alpha} in CYP7A1 Regulation Is Inhibited by a Key Lipogenic Activator, Sterol Regulatory Element-Binding Protein-1c. Mol. Endocrinol.
21: 2698-2712
[Abstract]
[Full Text]