ネソニア・ワスプのハプロディプロイド性決定の母体制御
Eveline C Verhulst1, Leo W Beukeboom, Louis van de Zande
1Evolutionary Genetics, Centre for Ecological and Evolutionary Studies, University of Groningen, Netherlands.
Science (New York, N.Y.)
|May 1, 2010
まとめ
csdロカスがないヒメノプテラの昆虫では,雌の発達は,ナソニア・ビトリペニス・トランスフォーマー (Nvtra) 遺伝子に依存しています. 母親のインプリントは雄性ジゴティックNvtraの転写を防止し,受精は女性の発達のために女性特有のスプライシングを誘発する.
科学分野:
- エントモロジー エントモロジー学
- 遺伝学 遺伝学とは
- 発達生物学 発達生物学について
背景:
- ハイメノプテラはハプロディプロイド性で,雄は不受精卵から,雌は受精卵から発達する.
- ミツバチApis melliferaは,性別を決定するために補足性性決定 (CSD) 部位を利用しています.
- csdロカスがないヒメノプテラの性別決定のメカニズムは,ほとんど不明のままである.
研究 の 目的:
- csdロキュスを欠いている寄生虫ウサギナソニアの性決定機構を解明する.
- ナソニアの女性の発達を制御する遺伝的要因と規制経路を特定する.
主な方法:
- 性別決定におけるナソニア・ビトリペニス・トランスフォーマー (Nvtra) 遺伝子の役割を調査した.
- 分析された母親のmRNA貢献とNvtra.のジゴティック転写.
- Nvtra.によって規制された女性特有のスプライシングのプロセスを調べました.
主要な成果:
- ナソニアにはCSDの位置がなく,別の性別決定経路を示している.
- 母親のNvtra mRNAとジゴティックNvtraトランスクリプションは,女性の発達に不可欠です.
- Nvtraは,女性特有のトランスクリプトを生成するために,自身のスプライシングを自己調節します.
- 母親のインプリントは,受精していない卵にジゴティックNvtraの転写を防止し,男性の発達につながります.
結論:
- ナソニアの性別決定システムは,CSDの場所ではなく,Nvtraの遺伝子調節に依存しています.
- 女性の発達は,母性インプリントとスプライシングのジゴティックNvtraオートレギュレーションによって制御されます.
- この研究は,ヒメノプテラの性決定の新しいメカニズムを明らかにしています.
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