分極化されたニューロンにおける脂質の移動に対する機能的障壁である

T Kobayashi¹, B Storrie, K Simons

¹Cell Biology Program, European Molecular Biology Laboratory, Heidelberg, Germany.

Nature

|October 15, 1992

まとめ

軸索のヒロック/初期セグメントの機能的障壁は,偏光ニューロンにおける膜の混合を防ぐ. この拡散障壁は,神経機能にとって極めて重要な,異なる軸索および体膜領域を維持する.

科学分野:

神経科学は神経科学である.
細胞生物学細胞生物学
分子生物学は分子生物学である.

背景:

極化ニューロンは,異なる軸索および dendritic 分子組織を示します.
グリコプロテインの分類の類似性は,上皮細胞と海馬の神経細胞の間に存在します.
ニューロンの異なるプラズマ膜領域を維持するメカニズムは,他の細胞タイプと異なる.

研究の目的:

アクソナルヒルロック/初期セグメントの機能的障壁の存在を調査する.
この障壁が,軸索領域と体幹領域の間の膜構成要素の混合を防ぐかどうかを判断する.

主な方法:

光フォスフォリピドを持つリポソームは,偏光ヒポキャンパスのニューロンのプラズマ膜に溶け込みました.
融合はpHの変化によって誘発され,インフルエンザウイルスヘマグルチニンによって媒介された.
ニューロンは鳥のペストウイルスに感染し,軸索表面にヘマグルーチニンを発現させました.

主要な成果:

光性脂質ラベリングは,融合後の軸索膜にのみ検出されました.
溶融した脂質は,軸索膜内の移動性を示した.
細胞体や dendritic 表面にラベリングは観察されず,制限された拡散を示しています.

結論:

アクソナルヒルロック/初期セグメントに拡散障壁が存在する.
この障壁は,アクソナルとソマトデンドリティックプラズマ膜領域の組成の違いを効果的に維持します.
この発見は,神経の極性を維持する機能的障壁の仮説を裏付けている.

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