DMYは,メダカ魚のオス発育に必要なY固有のDMドメイン遺伝子である

Masaru Matsuda¹, Yoshitaka Nagahama, Ai Shinomiya

¹Laboratory of Reproductive Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan.

Nature

|May 31, 2002

まとめ

研究者らは,メダカ魚の雄性性判定において,DMY遺伝子が決定的であることを確認した. DMYの変異により,XY魚は雌として発達し,丸の発達におけるその役割を強調した.

科学分野:

遺伝学遺伝学とは
発達生物学発達生物学とは
比較ゲノミクスとは

背景:

性別を決定するSry遺伝子は哺乳類で知られているが,非哺乳類の脊椎動物におけるその対称性については未だに不明である.
多様な種の性決定メカニズムを理解することは,進化的および遺伝的研究の鍵です.

研究の目的:

メダカ魚 (Oryzias latipes) の性決定遺伝子を特定するために.
候補遺伝子の testicular 発達における機能を調査する.

主な方法:

再結合ブレイクポイント分析とデレーション分析を使用して,メダカY染色体上の性別決定領域を狭めました.
ショットガンの配列解析により,この重要な領域内の遺伝子が特定されました.
遺伝子発現分析と変異研究が,候補遺伝子で実施された.

主要な成果:

性別を決定する領域は,Y染色体の250kbのセグメントに局在していた.
この領域で27の遺伝子が予測され,3つが性差別化時に発現した.
Y型特異遺伝子DMY (PG17) が特定され,XY型雌に変異がもたらされるため,男性の発達に不可欠であることが示されました.

結論:

DMYは,メダカ魚の丸発育に不可欠なY固有の遺伝子である.
DMYは,メダカの性決定遺伝子の主要候補である.
この発見は,脊椎動物の性決定の進化に光を当てている.

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