X不活性化プロファイルは,女性におけるX関連遺伝子発現の広範な変動性を明らかにしています
Laura Carrel1, Huntington F Willard
1Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA. lcarrel@psu.edu
Nature
|March 18, 2005
まとめ
X染色体内のほとんどの遺伝子は,雌性哺乳類では静止されています. しかし,約15%のX関連遺伝子は,この過程から逃れ,雌の間で発現の変動につながります.
科学分野:
- 遺伝学 遺伝学とは
- エピジェネティクス エピジェネティクス
- ヒューマン・バイオロジー ヒューマン・バイオロジー
背景:
- X染色体不活性化 (XCI) は,雌性哺乳類の1つのX染色体上のほとんどの遺伝子を静止させます.
- XCIから脱出する遺伝子は,性二形態の特徴と遺伝障害の多様性に影響を与える可能性があります.
- XCI脱出を理解することは,女性特有の生物学と病気を理解するために不可欠です.
研究 の 目的:
- 人間のX染色体のX不活性化プロフィールを包括的に作成する.
- XCIから脱出する遺伝子を特定し,その発現パターンを定量化する.
- 人間のX染色体全体でXCI脱出における地域差異を調査する.
主な方法:
- 人間の線維芽細胞系におけるX無活性化パターンの分析.
- 人間のX染色体における測定可能な遺伝子の約95%をプロファイリングする.
- 活性X染色体と非活性X染色体の遺伝子発現の定量化.
主要な成果:
- X-リンクされた遺伝子の約15%は,XCIからの脱出の程度を示しています.
- X-リンク遺伝子の有意な割合 (約10%) は,変数XCIパターンを示しています.
- XCIからの遺伝子脱出は,異なる染色体領域で劇的に異なります.
結論:
- ヒトのX染色体関連遺伝子のかなりの数は,X染色体の不活性化から逃れることができる.
- 女性における表現の異質性は,これまで認識されていたよりも広く存在しています.
- XCI脱出における地域差異は,性染色体の進化史を反映している可能性があります.
さらに関連する動画
12:42Quick Fluorescent In Situ Hybridization Protocol for Xist RNA Combined with Immunofluorescence of Histone Modification in X-chromosome Inactivation
Published on: November 26, 2014
08:27A Non-random Mouse Model for Pharmacological Reactivation of Mecp2 on the Inactive X Chromosome
Published on: May 22, 2019
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