心臓におけるミオシン重鎖遺伝子の調節
1Department of Internal Medicine, University of Arizona College of Medicine, Tucson.
Circulation
|May 1, 1993
まとめ
甲状腺ホルモン (T3) は,骨格筋プログラムとは無関係に心筋ミオシン重鎖 (MHC) 遺伝子発現を調節する. 異なる哺乳類はT3に対する反応が異なっており,アルファとベータMHCの遺伝子調節に影響を与えます.
科学分野:
- 心血管生物学 心血管生物学
- 分子遺伝学 分子遺伝学
- 遺伝子規制 遺伝子規制
背景:
- 心臓のミオシン重鎖 (MHC) アイソフォームは,心臓の機能に不可欠です.
- アルファおよびベータMHC遺伝子の調節を理解することは,心臓生理学の鍵です.
研究 の 目的:
- 心臓MHC遺伝子の調節に関する理解の進歩をレビューする.
- 甲状腺ホルモン (T3) と他の調節要素の役割を調査する.
主な方法:
- アルファおよびベータMHC遺伝子の分子クローン.
- 遺伝子発現の分析 in vivoおよび培養心臓細胞.
- 規制要素を特定するために,キメリックプラズミッドとトランス遺伝子動物の使用.
主要な成果:
- 心臓のMHC遺伝子発現はT3によって調節され,T3はα-MHCを刺激しβ-MHCを抑制する.
- T3反応性は,哺乳類の種によって著しく異なります.
- T3誘導,抑制,および筋肉特有の発現を制御する規制要素が特定されています.
結論:
- 心臓のMHC遺伝子調節は,骨格筋の肌性プログラムとは独立しています.
- MHC遺伝子プロモーター内の特定のDNA配列は,T3やその他の要因に対する反応を媒介する.
- 密接に結びついているアルファおよびベータ-MHC遺伝子の独立した調節により,心臓機能の微調整が可能になります.
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