ドロソフィラのハイブリッド不妊症の原因としての遺伝子転移

John P Masly¹, Corbin D Jones, Mohamed A F Noor

¹Department of Biology, University of Rochester, Rochester, NY 14627, USA. msly@mail.rochester.edu

Science (New York, N.Y.)

|September 9, 2006

まとめ

遺伝子転移は,ドロソフィラのハイブリッドの男性不妊症を引き起こす. 繁殖に不可欠な遺伝子は,種間の染色体を移動させ,その遺伝子を欠く不妊のハイブリッドを生じさせ,遺伝的変異なしに生殖的孤立を示した.

科学分野:

遺伝学遺伝学とは
進化生物学の進化生物学について
生殖生物学生殖生物学

背景:

繁殖的孤立は,種化にとって極めて重要です.
ハイブリッド不妊症は,種間の遺伝的不適合から生じる可能性があります.
遺伝子の調節と位置は,生育において重要な役割を果たします.

研究の目的:

Drosophila melanogaster-D. simulansのハイブリッドにおけるハイブリッド男性不妊症の遺伝的根拠を調査する.
これらのハイブリッドにおける男性不妊の原因となる特定の遺伝子を特定する.
生殖分離の原因となる遺伝子転移の役割を理解する.

主な方法:

遺伝子位置の違いを特定するための比較ゲノミクス.
遺伝子の存在と機能を確認するための分子分析.
男性の生育能力を評価するためのハイブリッド化実験.

主要な成果:

男性の生殖能力に不可欠な単一複製遺伝子であるJYAlphaが特定されました.
JYAlphaはD. melanogasterの染色体4とD. simulansの染色体3に位置しています.
ゲノム解析により,D. simulans系統の染色体3に転移したJYAlphaが明らかになった.
転置によるJYAlphaが欠けているハイブリッドは完全に不妊です.

結論:

配列進化ではなく,遺伝子転移が,生殖分離を引き起こす可能性があります.
JYAlpha遺伝子の動きは,ハイブリッドの男性不妊症の直接的な原因である.
このメカニズムは,ドロソフィラの種化のための新しい経路を強調しています.

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