Molecular Mechanisms of Expression of TSHR and Graves' Ophthaolmopathy
Grant-in-Aid for Scientific Research (C).
|Research Institution||Yamanashi Medical University|
HARAGUCHI Kazutaka Yamanashi Medical University, Assistant Professor, 医学部, 講師 (70165009)
IKEDA Masato Yamanashi Medical University, Medical Staff, 医学部, 医員 (20242638)
SHIMURA Hiroki Yamanashi Medical University, Assistant, 医学部, 助手 (40303416)
|Project Fiscal Year
1998 – 1999
Completed(Fiscal Year 1999)
|Budget Amount *help
¥3,300,000 (Direct Cost : ¥3,300,000)
Fiscal Year 1999 : ¥1,000,000 (Direct Cost : ¥1,000,000)
Fiscal Year 1998 : ¥2,300,000 (Direct Cost : ¥2,300,000)
|Keywords||thyrotropin receptor / adipocyte / cytokine / differentiation / TSH受容体 / 脂肪細胞 / 分化|
We have shown that functional TSHR has been expressed in rat adipose tissue and 3T3-L1 cells upon differentiation. Since the amount of expressed TSHR approaches to that of thyroid and also enlargement of fat tissue has been reported in Graves' ophthalmopathy, we believe that the exploration of mechanisms of TSHR expression is important for the understanding of pathogenesis of Graves' ophthalmopathy. Using rat preadipocyte and 3T3-L1 cultured cells, we obtained the findings below.
1 ) Dedifferentiation of adipocyte by cytokines such as TGFィイD2βィエD2, TNFィイD2αィエD2 and IFNィイD2γィエD2 was accomopanied by the decreased expression of TSHR.
2)Stimulation of differentiation of adipocytes by PPARィイD2γィエD2 activators was accompanied by the increased expression of TSHR whose responsiveness to TSH was well conserved.
3)Transfection of preadipocytes with PPARg expressing adenovirus enhanced the PPARg activators on its actionon TSHR expression.
4)Deoxyribonuclease 21 protection showed that nuclear extracts from differentiated 3T3-L1 cells strongly protected two sequences from -146 to -127 and -112 to -106 containing Ets-binding sites.
5)We found two new nuclear proteins which binds to putative Ets binding site of TSHR, one decreased upon differentiation whereas the other increased.
Using southwestern analysis, we are now trying to identify and get clonnes of the new nuclear proteins.
2:-146から-90に脂肪特異的、分化特異的発現を制御する部位が存在し、特に-146から-127のCRE likeの配列と-112から-106のEts融合部位が重要と考えられた.このことはdeletion mutantおよびfoot printの両実験において明らかとした.
Research Output (9results)