メラノプシンを含む網膜のギャングリア細胞:構造,投影,および固有の光敏感性
1Howard Hughes Medical Institute and Department of Neuroscience, Johns Hopkins University School of Medicine, 725 North Wolfe Street, Baltimore, MD 21205-2185, USA.
まとめ
メラノプシン (Melanopsin) は網膜のギャングリア細胞 (RGCs) の視覚性色素であり,昼夜光学訓練を駆動する. この発見は,光信号が,画像を形成しない視覚機能を通じて哺乳類の生物学的時計をどのように設定するかを明らかにしています.
科学分野:
- 神経科学は神経科学である.
- クロノバイオロジー クロノバイオロジー
- 分子生物学は分子生物学である.
背景:
- 上神経核 (SCN) は哺乳類の昼間ペースメーカーとして機能する.
- 目からの光信号は,網膜下垂体経路経由でSCNに光誘導します.
- 棒と円の細胞は,この光誘導プロセスには不可欠ではありません.
研究 の 目的:
- SCNのフォトトレーニングにおけるメラノプシンの役割を調査する.
- 画像を形成しない視覚機能に責任を負う特定の光受容体を特定する.
- メラノプシンがこれらの特殊な網膜のギャングリアン細胞 (RGCs) の視覚染色体として機能するかどうかを判断する.
主な方法:
- ネズミのメラノプシンをクローニングし,特定の抗体を生成する.
- ネズミのRGCでメラノプシン局所化を検出するための免疫ヒストキミカル分析.
- tau-lacZトランスジェニックマウスを利用して,SCNへのRGC投影を追跡する.
主要な成果:
- メラノプシンは,ネズミのRGCsのサブセットの細胞体,デンドライト,および近接軸索で検出されました.
- ベータ-ガラクトシダゼ陽性RGC (メラノプシン遺伝子発現を示す) からのアクソンがSCNおよび他の関連する脳核に投影される.
- 本質的に光感受性の高いラットRGCsは,一貫して表現されたメラノプシンである.
結論:
- メラノプシンは,光伝導性RGCにおける視覚的染色体として強く示されています.
- メラノプシンを含むRGCは,日中時計の設定に不可欠です.
- メラノプシンは,日中照射運動と瞳孔の光反射を含む,画像を形成しない視覚機能を促進します.
関連する概念動画
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