マウスにおけるRb変異の効果
T Jacks1, A Fazeli, E M Schmitt
1Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, Cambridge 02142.
Nature
|September 24, 1992
まとめ
網膜芽細胞腫遺伝子 (Rb) は,がんの予防に不可欠です. ネズミの1つのRb遺伝子コピーを破壊すると,網膜芽細胞腫は発生しませんが,細胞死と欠陥のある血液形成により,下垂体腫瘍と胚死亡を引き起こします.
科学分野:
- 腫瘍学 腫瘍学
- 遺伝学 遺伝学とは
- 発達生物学 発達生物学とは
背景:
- 網膜芽細胞瘤遺伝子 (Rb) は,ヒトの癌で頻繁に変異する確立された腫瘍抑制遺伝子です.
- Rbの機能を理解することは,がんの研究と治療の開発に不可欠です.
研究 の 目的:
- 網膜芽細胞腫 (Rb) 遺伝子のインビボ機能を研究するために,Rbアレルが破壊されたマウスモデルを作成しました.
- Rb遺伝子障害が腫瘍の発達と胚の生存能力に及ぼす影響を決定する.
主な方法:
- 網膜芽細胞腫 (Rb) 遺伝子の1つのアルレルが破壊されたマウス株の生成.
- 腫瘍の監視と胚の発達評価を含む,ヘテロゾイゴスおよびホモゾイゴス変異性マウスのフェノタイプ分析.
主要な成果:
- ヘテロジゴス型Rb障害マウスは,網膜芽細胞腫を発症しなかったが,野生型Rbアレルがない細胞では,下垂体腫瘍への予備性を示した.
- ホモジゴスRb障害の胚は,妊娠14〜15日の間に死亡率を示した.
- 胚の致死性は,広範囲にわたるニューロン細胞死と赤血球形成の障害と関連していました.
結論:
- 網膜芽細胞腫 (Rb) 遺伝子は,下垂体腫瘍形成を予防する上で重要な役割を果たします.
- Rb機能の完全な喪失は,胚の発達に不可欠であり,神経生成と血液形成に影響を与えます.
- このマウスモデルは,Rbががんと発達における多面的な役割を研究するための貴重なツールを提供します.
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