のネズミの電圧誘導ナトリウムチャネルは,樹皮のの毒素に対して防御します

Ashlee H Rowe¹, Yucheng Xiao², Matthew P Rowe³

¹Section of Neurobiology, The University of Texas at Austin, Austin, TX 78712, USA.

Science (New York, N.Y.)

|October 26, 2013

まとめ

のマウスは,独特の Nav1.8 チャンネル変種を持ち,樹皮のの毒素と結合し,痛み信号を遮断します. この適応により,毒性のある Scorpions を狩り,激しい痛み反応を克服することができます.

科学分野:

神経科学は神経科学である.
進化生物学の進化生物学について
毒理学毒理学毒理学

背景:

痛みは,組織損傷をシグナリングすることによって,適応的機能を果たします.
樹皮ののような有毒な動物は,肉食動物を抑止するために痛ましい毒を使用します.
肉食動物は,痛みの反応が低下し,実際の組織損傷の検出が低下するリスクが進化します.

研究の目的:

のネズミが痛ましい毒にもかかわらず,樹皮のを捕食するメカニズムを調査する.
リスの毒害に対するのマウスの痛み抵抗の分子基礎を理解するために.

主な方法:

家ネズミとネズミの間の電圧ゲートされたナトリウムチャネル (Nav) 変数の比較分析.
樹皮の毒毒素と異なるNavチャネルサブタイプとの相互作用をテストするための生化学分析.
毒-毒素/ナブチャネル相互作用がニューロン活動に与える影響を評価するための電気生理学的記録.

主要な成果:

樹皮のの毒は哺乳類のNav1.7チャンネルを活性化し,痛みを誘発する.
のネズミは,そのNav1.8チャネルにユニークなアミノ酸の変種を持っています.
これらのNav1.8変種は,樹皮のの毒素と結合し,ナトリウム電流を阻害し,痛み信号の伝送を阻害します.

結論:

草のマウスは,ナブ1.8で特定の分子適応を進化させ,樹皮のの毒を中和させました.
この適応により, skorpion stingによって引き起こされる痛みを克服し,捕食を可能にします.
この研究は,毒素-チャネル共同進化を含む捕食者-獲物の相互作用における新しい戦略を明らかにしています.

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