Analysis of transcription enhancing factor for PTH receptor that controls bone metabolism
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
Functional basic dentistry
|Research Institution||Ohu University|
KAWANE Tetsuya Ohu University, School of Dentistry, Lecturer, 歯学部, 講師 (00265208)
MAEDA Toyonobu Ohu University, School of Dentistry, Assistant, 歯学部, 助手 (10382756)
HORIUCHI Noboru Ohu University, School of Dentistry, Professor, 歯学部, 教授 (00107294)
|Project Period (FY)
2005 – 2006
Completed(Fiscal Year 2006)
|Budget Amount *help
¥3,500,000 (Direct Cost : ¥3,500,000)
Fiscal Year 2006 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 2005 : ¥2,300,000 (Direct Cost : ¥2,300,000)
|Keywords||PTH / PTHrP receptor / osteoblast / PTHrP / transcriptional factor / siRNA / promoter / initiator / gel mobility shift assay / south western|
Parathyroid hormone (PTH) and PTH related protein (PTHrP) exert their effects on bone metabolism by binding to the G protein-coupled PTH/PTHrP receptor (PTH1R) expressed on osteoblasts. They increase expression one of the osteoclast activating factor (RANKL) and enhance bone resorption.
The rat, mouse and human PTH1R genes contain four 5' noncoding exons (U1, U2, U3 and U4) and three promoter regions. A TATA-like promoter upstream of exon U1 is referred to as the P1 promoter and a GC-rich promoter upstream of exon U3 and U4 is called the P2 and P3 promoters respectively. In rats, the downstream promoter (P2) was active in a variety of tissues including bone and kidney, while the upstream promoter (P1) was tissue-specific, showing activity in the kidney and the ovary.
In the present study, we attempted to analyze the mechanism of transcription related factor(s) and transcription enhancing factors on the promoter P2 of the PTH1R in the rat osteoblasts. The results were as follows.
1. The GC
box located in the -128/-2 region in the rat PTH1R U3 promoter (P2) was performed as an enhancer and could be replaced by the SM probe that was known as Sp1 and MAZ binding sequence.
2. The PTH1R mRNA expressed after 12-day of osteoblastic differentiation in ST2 cells. On the other hands, both Sp1 and MAZ mRNA expressed in all period of osteoblastic differentiation (after 0-day) in ST2 cells.
3. The Sp1 mRNA expressed in all tissues examined. A pattern of PTH1R mRNA expression was quite different from that of MAZ mRNA expression.
4. The PTH1R mRNA expression was suppressed by a knockdown of Sp1 or Maz in UMR-106 cells.
5. The PTH1R gene U3 promoter activities were suppressed by a knockdown of Sp1 in UMR-106 cells.
6. The PTH1R mRNA expressed after 12-day of osteoblastic differentiation in ST2 cells. On the other hands, osterix mRNA expressed after 8-day of osteoblastic differentiation in ST2 cells.
7. A pattern of tissue distribution of PTH1R mRNA expression was quite similar to that of osterix mRNA expression.
8. The PTH1R mRNA expression was suppressed by a knockdown of osterix in UMR-106 cells.
9. The PTH1R gene U3 promoter activities were not suppressed by a knockdown of osterix in UMR-106 cells. Less
Research Products (2results)