ホメオドメインの異常なタンパク質であるHOPによって心臓の成長と発達を調節する
Chong Hyun Shin1, Zhi-Ping Liu, Robert Passier
1Department of Molecular Biology, University of Texas Southwestern Medical Center at Dallas, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA.
Cell
|September 26, 2002
まとめ
新種のタンパク質であるHOPは,血清応答因子 (SRF) と相互作用することで,心臓の発達を調節する. その欠如は,心臓細胞の成長と分化における不均衡を引き起こし,心臓の異常を引き起こします.
科学分野:
- 心血管生物学 心血管生物学
- 発達生物学 発達生物学とは
- 分子遺伝学 分子遺伝学
背景:
- 発達中の心臓は,心筋細胞の増殖と分化を正確に調節することに依存しています.
- ホメオドメインのタンパク質は,心臓の発達において重要な役割を果たし,しばしば転写因子として作用する.
- 血清応答因子 (SRF) は,筋肉の発達と細胞の成長に関与する遺伝子の重要な調節因子です.
研究 の 目的:
- 新しく発見されたホメオドメインのタンパク質であるHOPを特徴づけ,心臓の発達におけるその役割を明らかにする.
- HOPが心筋細胞の増殖と分化に影響を与えるメカニズムを調査する.
- HOP欠乏が心臓の形質変異に及ぼす影響を決定する.
主な方法:
- HOPホメオドメインタンパク質の識別と特徴付け.
- 発達中の心臓におけるHOP発現パターンの分析,Nkx2.5.5への依存を含む.
- HOPがDNAと相互作用し,SRFの活動に与える影響を評価するためのインビトロ研究.
- HOP欠乏マウスの生成とフェノタイプ分析.
主要な成果:
- HOPは,Nkx2.5.5に依存する,発達中の心臓で高度に表現される単純なホメオドメインタンパク質です.
- HOPはDNAに結合しませんが,血清応答因子 (SRF) の活性に敵対します.
- ホモジゴスHOPヌルマウスは,心筋筋細胞の過剰または欠乏を含む変数心筋現象型を示します.
結論:
- HOPは,心臓発達の過程でSRF活動の重要な調節剤として作用します.
- HOPの欠如は,心筋細胞の増殖と分化とのバランスを乱します.
- HOPの調節不良は,心筋細胞ホメオスタシスの障害による異常な心臓形態変異につながる.
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