H+/K+-ATPaseと細胞膜ポテンシャルにおける非対称性は,左-右のパターニングの非常に初期の段階である
Michael Levin1, Thorleif Thorlin, Kenneth R Robinson
1Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
Cell
|October 10, 2002
まとめ
陽子ポンプ (H+とK+ATPアゼ) は,Xenopus胚の左-右の体非対称性を確立するために不可欠です. このトランスポーターを妨害すると,身体軸形成と遺伝子発現パターンがランダム化されます.
科学分野:
- 発達生物学 発達生物学について
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- 左-右 (LR) 体の非対称性は,適切な臓器の位置と機能に不可欠です.
- 初期のLR軸の決定の基礎となる分子機構は,まだ完全に理解されていません.
- イオン輸送は発達プロセスに絡み合っているが,LR非対称性における特定の役割は不明である.
研究 の 目的:
- LRの体軸方向の確立におけるH+とK+ATPアゼトランスポーターの役割を調査する.
- 種間のLR非対称性決定において,H+およびK+ATPアゼ活性が保たれているかどうかを決定する.
主な方法:
- Xenopusの胚におけるH+およびK+ATPアゼの活性に対する薬理学的抑制.
- mRNAの局所化と遺伝子発現パターンの分析.
- 臓器の位置と身体の軸方向の評価.
主要な成果:
- 薬理学的スクリーニングでは,H+とK+ATPアゼが,Xenopus.のLR軸方向化に不可欠であると特定されました.
- H+ と K+ ATPase mRNAの局所化は,Xenopusの発達初期に不対称になります.
- Xenopusとチキン胚の両方のH+とK+ATPアゼの混乱は,ランダム化されたLR非対称性と誘発された臓器ヘテロタクシアを引き起こしました.
結論:
- H+ と K+ ATPase トランスポーターは,LRの非対称性決定において,保存され,重要な役割を果たします.
- H+ と K+ ATP 酵素の活性によって媒介される初期の微分イオン流は,LR 体軸の確立に不可欠である.
- このイオン輸送機構は,非対称的な遺伝子発現パターンの主要な上流調節器である.
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