Transcriptional regulation of dentin matrix protein 1 by JunB and p300 during osteoblast differentiation.
Dentin matrix protein 1 (DMP1) is an acidic noncollagenous protein localized specifically in the mineralized matrix of bone and dentin. Expression analyses demonstrate that DMP1 is differentially regulated in osteoblasts and odontoblasts. Earlier we have reported on the transcriptional regulation of DMP1 by c-Fos and c-Jun (AP-1) transcription factors. Results from earlier study indicate that c-Fos and c-Jun play an important role in early osteoblast differentiation, whereas they do not have a significant effect on the terminally differentiated osteoblasts. In this paper, we demonstrate a regulatory mechanism by which JunB transcriptionally controls the expression of DMP1 during osteoblast differentiation. The cooperative interaction of JunB with p300 has been shown to dramatically modulate the DMP1 promoter activity during mineralization. Immunoprecipitation and chromatin immunoprecipitation analysis demonstrate the interaction of JunB and p300 in vivo. Further, phosphorylation of JunB at Ser-79 was found to be essential for its interaction with p300. Intrinsic histone acetyltransferase activity of p300 also plays a critical role in regulating DMP1 gene expression.
Department of Oral Biology, College of Dentistry, University of Illinois, Chicago, Illinois 60612, USA.
Karthikeyan
K
Narayanan
Rampalli
R
Srinivas
Mathew Craig
MC
Peterson
Amsaveni
A
Ramachandran
Jianjun
J
Hao
Bayar
B
Thimmapaya
Philipp E
PE
Scherer
Anne
A
George
D016475:3T3 Cells; D000123:Acetyltransferases / Q000378:metabolism; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000378:metabolism; D002843:Chromatin / Q000378:metabolism; D050881:E1A-Associated p300 Protein; D004791:Enzyme Inhibitors / Q000494:pharmacology; D016326:Extracellular Matrix Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation; D005982:Glutathione Transferase / Q000378:metabolism; D051548:Histone Acetyltransferases; D047468:Immunoprecipitation; D008156:Luciferases / Q000378:metabolism; D051379:Mice; D008954:Models, Biological; D016297:Mutagenesis, Site-Directed; D009687:Nuclear Proteins / Q000378:metabolism*; D009804:Odontoblasts / Q000378:metabolism; D010006:Osteoblasts / Q000378:metabolism; D010750:Phosphoproteins; D010766:Phosphorylation; D010957:Plasmids / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism*; D012313:RNA / Q000378:metabolism; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism*; D014158:Transcription, Genetic; D014162:Transfection; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
D002843:Chromatin; C513308:Dmp1 protein, mouse; C081635:Dmp1 protein, rat; D004791:Enzyme Inhibitors; D016326:Extracellular Matrix Proteins; D009687:Nuclear Proteins; D010750:Phosphoproteins; D016755:Proto-Oncogene Proteins c-jun; D011993:Recombinant Fusion Proteins; D015534:Trans-Activators; D012694:Serine; D012313:RNA; D008156:Luciferases; D000123:Acetyltransferases; D050881:E1A-Associated p300 Protein; C494361:Ep300 protein, mouse; C494362:Ep300 protein, rat; D051548:Histone Acetyltransferases; D005982:Glutathione Transferase; D048051:p38 Mitogen-Activated Protein Kinases