網膜の方向選択性回路における配線特異性
Kevin L Briggman1, Moritz Helmstaedter, Winfried Denk
1Max Planck Institute for Medical Research, Department of Biomedical Optics, Heidelberg 69120, Germany. briggman@mpimf-heidelberg.mpg.de
Nature
|March 11, 2011
まとめ
ネズミの網膜における神経回路配線の非対称性は,スターバーストのアマクリン細胞が方向選択性ギャングリオン細胞と接続する方法を形作ります. この構造的非対称性は,指向運動を検出する鍵であり,神経コンピューティングの理解を前進させます.
科学分野:
- 神経科学は神経科学である.
- 計算神経科学とは
- 細胞神経科学は細胞神経科学である.
背景:
- ニューロンの接続性は,網膜の運動検出を含むニューラルコンピューティングに不可欠です.
- 電子顕微鏡はニューロン接続性の分析を可能にしますが,高解像度データ取得のスケーリングは依然として課題です.
研究 の 目的:
- スターバーストアマクリン細胞とマウスの方向選択性ギャングリオン細胞の間の特定のシナプス結合を調査する.
- 構造線路の非対称性が網膜の方向選択性に寄与するかどうかを判断する.
主な方法:
- 高解像度ニューロン追跡のためのシリアルブロックフェイス電子顕微鏡.
- 神経活動の機能的分析のための2フォトンカルシウムイメージング.
主要な成果:
- スターバースト・アマクリン細胞のデンドライトは,方向選択性のあるギャングリオン細胞と高度に特異的なシナプスを形成します.
- シナプス結合は,ギャングリオン細胞の好ましい方向に依存しています.
- 構造的な配線不対称性が特定され,方向選択性計算に寄与しました.
結論:
- ニューロンの配線における構造的非対称性は,網膜の方向選択性において重要な役割を果たします.
- 発見は,方向選択性の特定のモデルを支持し,発達理論を制約する.
- 機能的イメージングと大規模電子顕微鏡の組み合わせは,複雑な神経生物学的な問題に対して有効です.
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