光伝導性刺激によって誘発されたシナプスアクチンの改造

M A Colicos¹, B E Collins, M J Sailor

¹Neurobiology Section/Division of Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.

Cell

|December 6, 2001

まとめ

アクティビティは,記憶形成の重要なプロセスであるシナプスの構造的変化を誘発する. この研究は,シナプスにおけるアクチンリモデリングが,新しい,活発な接続につながる方法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.
細胞生物学細胞生物学
シナプスの可塑性

背景:

使用依存シナプス改造は,メモリエンコーディングのための提案されたメカニズムです.
アクティビティ依存シナプス可塑性の構造的根拠については,依然として議論されている.

研究の目的:

活動に依存する形態学的シナプス可塑性を実証する.
シナプスの再構築におけるアクチンダイナミクスの役割を明らかにする.

主な方法:

シナプス活動を誘発する光伝導刺激.
個々のシナプスにおけるGFP-アクチンのビデオイメージング.
グルタミン酸受容体の依存性と,活性シナプスのFM5-95ラベリングを利用する.

主要な成果:

単一のテタニック刺激は,シナプスの一時的なアクチンシフトを引き起こす.
繰り返しの刺激により,安定したグルタミン酸受容体依存のシナプス再構築が誘発されます.
プレシナプスアクトンの再分布と新しい点の形成が観察されました.
ポストシナプスアクチンは,シナプス前部位に向かって投影し,シナプトゲネシスを模倣します.

結論:

シナプスの活動に依存する構造的可塑性が確認されています.
プレシナプスアクチンリモデリングは,新しい活性プレシナプス端末の形成を促進します.
これは,永続的なメモリエンコーディングのためのセルラーメカニズムを提供します.

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