X染色体不活性化は,XOヒトとマウスの生存能力の違いを説明する可能性がある
A Ashworth1, S Rastan, R Lovell-Badge
1Chester Beatty Laboratories, Institute of Cancer Research, London, UK.
Nature
|May 30, 1991
まとめ
ターナー症候群のヒトXOコンセプトスは,遺伝子用量の問題により,めったに生存できません. 生存可能なXOマウスは,種特有のX染色体不活性化メカニズムが生存の鍵であることを示唆しています.
科学分野:
- 遺伝学 遺伝学とは
- 発達生物学 発達生物学について
- 比較ゲノミクスとは
背景:
- 人間のXOコンセプトス (ターナー症候群) は,高胚死亡率と変異的な現象型を示しています.
- この致死性は,X染色体とY染色体遺伝子のモノソミーから生じると考えられ,投与量の補償に不可欠である.
- ZFXやRPS4Xのような遺伝子は,活性X染色体と非活性X染色体の両方に存在しているため,ターナー症候群に関与しています.
研究 の 目的:
- XO哺乳類の生存能力におけるX染色体不活性化の役割を調査する.
- 人とマウスのX関連遺伝子に関する遺伝子用量補償メカニズムを比較する.
主な方法:
- マウスのX染色体不活性化を分析するシステムの開発.
- マウスのX染色体におけるZfxとRps4Xの不活性化パターンの評価.
主要な成果:
- ZfxとRps4Xの両方がマウスの正常なX不活性化を経験することを実証しました.
- XOマウスは生存可能で,肥沃で,解剖学的に正常であり,人間のXO致死性とは対照的であることが観察されました.
結論:
- 重要なX関連遺伝子の用量補償の達成における種別差異は,ヒトのXO概念の使用の致死性と比較して,XOマウスの生存可能性を説明する可能性がある.
- X不活性化メカニズムは,哺乳類の発達と生存において極めて重要な役割を果たし,種間の有意な変動がある.
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
関連する概念動画
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Around 300 million years ago, the two sex chromosomes diverged from two identical autosomal chromosomes. Over time, the Y chromosome has lost most of its genes, shrinking in size. Today,...
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The human X chromosome contains over ten times the number of genes as in the Y chromosome. Since males have only one X chromosome, and females have two, one might expect females to produce twice as many of the proteins, with undesirable results.
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