ヒストン脱メチラーゼJHDM2Aは,Tnp1とPrm1の転写と精子生成に不可欠です

Yuki Okada¹, Greg Scott, Manas K Ray

¹Howard Hughes Medical Institute, Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-7295, USA.

Nature

|October 19, 2007

まとめ

マウスのヒストン脱メチラーゼJHDM2Aは精子生成に不可欠です. JHDM2Aの喪失は,重要な遺伝子発現に影響を与えることで,精子染色体凝縮の欠陥を引き起こす.

科学分野:

エピジェネティクスと分子生物学
生殖生物学生殖生物学
クロマチンの規制

背景:

ヒストンのメチル化は,可逆的な表遺伝的変異である.
LSD1およびJmjCドメインのタンパク質を含むヒストン脱メチラゼは,ヒストンからメチル群を除去する.
動物モデルにおけるほとんどのヒストンデメチラゼの生物学的な役割は,まだ十分に理解されていない.

研究の目的:

H3K9me2/1に特異的なヒストン脱メチラーゼJHDM2Aの機能を in vivoで調査する.
機能喪失アプローチを用いて精子生成におけるJHDM2Aの役割を明らかにする.

主な方法:

機能喪失戦略を用いて,Jhdm2a欠乏したマウスを生成した.
分析されたクロマチンの凝縮欠損は,メオチス後の精子.
JHDM2Aが標的遺伝子に結合し,その発現に及ぼす影響について調査した.

主要な成果:

Jhdm2a欠乏したマウスは,メオティック後クロマチンの濃縮欠陥を顕著に示した.
JHDM2Aは,トランジション核タンパク質1 (Tnp1) とプロタミン1 (Prm1) の遺伝子に直接結合し,その発現を調節することが判明しました.
Tnp1とPrm1の遺伝子産物は,精子の染色体包装と凝縮に不可欠である.

結論:

JHDM2Aは哺乳類の精子生成に不可欠な役割を果たしています.
JHDM2AはTnp1とPrm1の発現を直接制御し,精子の染色体成熟におけるその機能を強調しています.
この研究では,JHDM2Aが男性のゲメトゲネシスのプロセスにおける重要なレギュレータとして特定されています.

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