ドロソフィラの兄弟種であるドロソフィラのハイブリッド不妊性タンパク質による変化したヘテロクロマチン結合
Joshua J Bayes1, Harmit S Malik
1Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98185, USA.
Science (New York, N.Y.)
|November 26, 2009
まとめ
ハイブリッドの男性不妊症は,オデュッセウスのサイトホメオボックス (OdsH) 遺伝子から生じる. ヘテロクロマチンの急速な進化は,OdsHに影響を与える.
科学分野:
- 遺伝学と進化生物学について
- 生殖分離のメカニズムは,生殖分離のメカニズムです.
- 専門分野の研究は,専門分野の研究である.
背景:
- ヘテロガメティック性の性におけるハイブリッド不妊症は,早期に進化するポストジゴティック生殖障壁である.
- ハイブリッド不妊症の分子基盤は,ほとんど解明されていないままです.
- これらの障壁を理解することは,種化を理解するために極めて重要です.
研究 の 目的:
- ハイブリッドの男性不妊症の分子基盤を調査するために.
- この過程におけるオデッセウスサイトホメオボックス (OdsH) 遺伝子の役割を特定する.
- ヘテロクロマチン進化が生殖分離に与える影響を調査する.
主な方法:
- オデッセウスサイトホメオボックス (OdsH) の遺伝子識別と特徴付け.
- ヘテロクロマティック領域内のタンパク質の局所化に関する研究.
- ドロソフィラハイブリッドの雄 (D. mauritiana x D. simulans) でのOdsH機能の比較分析.
- 滅菌したハイブリッドの精巣における精子生成の検査.
主要な成果:
- OdsH遺伝子は,ダイナミックなヘテロクロマティックロシに局所するタンパク質をコードし,脱凝縮を引き起こします.
- D. mauritiana x D. simulansの雄性ハイブリッドでは,D. mauritiana OdsH (OdsHmau) は,D. simulans Y染色体と相互作用することで,滅菌因子として作用する.
- D. simulans OdsH (OdsHsim) は不妊の原因ではありません.
- 精子生成中のOdsHの豊富性と局所性の違いは,ハイブリッドの不妊性と相関しています.
結論:
- ヘテロクロマチンの急速な進化は,ハイブリッド男性不妊症の発症の重要な要因である.
- オデッセウスサイトホメオボックス (OdsH) 遺伝子は,ヘテロクロマチン相互作用を通じてハイブリッド不妊を媒介する上で重要な役割を果たしています.
- 種間の異なる OdsH 機能は,種化中に生殖的孤立に貢献します.
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