CRYPTOCHROMEは,ニューロンの発火速度を調節するブルーライトセンサーです
Keri J Fogle1, Kelly G Parson, Nicole A Dahm
1Department of Physiology and Biophysics, University of California-Irvine, Irvine, CA 92697, USA.
Science (New York, N.Y.)
|March 10, 2011
まとめ
フルーツハエは,脳の神経細胞に新しい光感知メカニズムを持っています. CRYPTOCHROME (CRY) が介在するこの経路は,ニューロンが伝統的な光受容体なしで光に直接反応することを可能にします.
科学分野:
- 神経科学は神経科学である.
- 分子生物学は分子生物学である.
- クロノバイオロジーはクロノバイオロジーを用います.
背景:
- 神経光の反応は,通常,オプシンタンパク質と外部の光受容体に依存しています.
- 中央脳ニューロンの直接光感受性は,特にオプシンなしでは,あまり理解されていません.
研究 の 目的:
- ドロソフィラ・メラノガスターのオプシン媒介ではない光反応を調査する.
- この直接的なニューロンの光感受性に関与する分子機構と細胞成分を特定する.
主な方法:
- 遺伝子操作によるDrosophila melanogasterモデルを利用した.
- 光刺激への反応として測定された神経活動と膜潜在変化.
- CRYPTOCHROME (CRY) とカリウムチャネルの役割を調査した.
主要な成果:
- 大型の横側腹部刺激ニューロン (lLNvs) は,数秒以内に,光によって誘発されたアクションポテンシャルを発現します.
- この反応は青い光に対する波長選択であり,CRYPTOCHROME (CRY) の感度と一致する.
- lLNvsにおけるCryptochrome (CRY) 表現は,オプシンとは独立して,光応答性のために必要かつ十分である.
- このメカニズムは,昼間CRY-TIMELESS相互作用とは異なるフラビンリドックスとカリウムチャネル伝導性を含む.
結論:
- ドロソフィラの中枢ニューロンは,CRYPTOCHROME (CRY) を介して直接光を感知することができます.
- このCRYPTOCHROME (CRY) に依存する経路は,ニューロンの光検出のための新しいメカニズムを提供します.
- この発見は,脳における非視覚的な光知覚の理解を広げている.
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