Epigenetic Regulation of BMP2 by 1,25-dihydroxyvitamin D3 through DNA Methylation and Histone Modification
Open Access
- 19 April 2013
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 8 (4), e61423
- https://doi.org/10.1371/journal.pone.0061423
Abstract
Genetic hypercalciuric stone-forming (GHS) rats have increased intestinal Ca absorption, decreased renal tubule Ca reabsorption and low bone mass, all of which are mediated at least in part by elevated tissue levels of the vitamin D receptor (VDR). Both 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and bone morphogenetic protein 2 (BMP2) are critical for normal maintenance of bone metabolism and bone formation, respectively. The complex nature of bone cell regulation suggests a potential interaction of these two important regulators in GHS rats. In the present study, BMP2 expression is suppressed by the VDR-1,25(OH)2D3 complex in Bone Marrow Stromal Cells (BMSCs) from GHS and SD rat and in UMR-106 cell line. We used chromatin immunoprecipitation (ChIP) assays to identify VDR binding to only one of several potential binding sites within the BMP2 promoter regions. This negative region also mediates suppressor reporter gene activity. The molecular mechanisms underlying the down-regulation of BMP2 by 1,25(OH)2D3 were studied in vitro in BMSCs and UMR-106 cells using the DNA methyltransferase inhibitor 5-aza-2'-deoxycytidine (DAC) and the histone deacetylase inhibitor trichostatin A (TSA). Both DAC and TSA activate BMP2 expression in combination with 1,25(OH)2D3. Bisulfite DNA pyrosequencing reveals 1,25(OH)2D3 to completely hypermethylate a single CpG site in the same BMP2 promoter region identified by the ChIP and reporter gene assays. ChIP assays also show that 1,25(OH)2D3 can increase the repressive histone mark H3K9me2 and reduce the acetylation of histone H3 at the same BMP2 promoter region. Taken together, our results indicate that 1,25(OH)2D3 binding to VDR down-regulates BMP2 gene expression in BMSCs and osteoblast-like UMR-106 cells by binding to the BMP2 promoter region. The mechanism of this 1,25(OH)2D3-induced transcriptional repression of BMP2 involves DNA methylation and histone modification. The study provides novel evidence that 1,25(OH)2D3 represses bone formation through down-regulating BMP2 expression both in vivo and in vitroThis publication has 50 references indexed in Scilit:
- Structure and Function of Histone H3 Lysine 9 Methyltransferases and DemethylasesChemBioChem, 2011
- Elevated vitamin D receptor levels in genetic hypercalciuric stone-forming rats are associated with downregulation of SnailJournal of Bone and Mineral Research, 2010
- Repressive BMP2 gene regulatory elements near the BMP2 promoterBiochemical and Biophysical Research Communications, 2010
- Genetic Hypercalciuric Stone-Forming Rats Have a Primary Decrease in BMD and StrengthJournal of Bone and Mineral Research, 2009
- Lineage-Specific Polycomb Targets and De Novo DNA Methylation Define Restriction and Potential of Neuronal ProgenitorsMolecular Cell, 2008
- Genome-Wide Profiling of DNA Methylation Reveals a Class of Normally Methylated CpG Island PromotersPLoS Genetics, 2007
- Distribution, silencing potential and evolutionary impact of promoter DNA methylation in the human genomeNature Genetics, 2007
- A genome-wide analysis of CpG dinucleotides in the human genome distinguishes two distinct classes of promotersProceedings of the National Academy of Sciences of the United States of America, 2006
- A new mathematical model for relative quantification in real-time RT-PCRNucleic Acids Research, 2001
- Effects of BMP-2, BMP-4, and BMP-6 on Osteoblastic Differentiation of Bone Marrow-Derived Stromal Cell Lines, ST2 and MC3T3-G2/PA6Biochemical and Biophysical Research Communications, 1996