神経筋肉のシナプス組織とターゲット選択におけるトランスシナプス・テヌーリンのシグナル伝達
Timothy J Mosca1, Weizhe Hong, Vardhan S Dani
1Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, California 94305, USA. tmosca@stanford.edu
Nature
|March 20, 2012
まとめ
テヌーリンは,ドロソフィラの神経筋シナプスの組織化に不可欠です. これらのタンパク質は,シナプス前とシナプス後の構造を調整し,適切なシナプス組立と機能を保証し,標的の選択を誘導します.
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.
- 発達生物学 発達生物学とは
背景:
- シナプスの組み立ては,トランスシナプス信号に依存しますが,重要な組織化分子は完全に理解されていません.
- テヌーリンは,大型の細胞外ドメインを持つ保存されたトランスメブランタンパク質で,表皮成長因子 (EGF) -リピートが特徴です.
研究 の 目的:
- 神経筋シナプスの組織と標的の選択におけるドロソフィラ・テネウリン (Ten-mとTen-a) の役割を調査する.
- テヌリンがシナプスの発達に寄与する分子メカニズムを解明する.
主な方法:
- Drosophila melanogasterをモデル生物として利用しました.
- テン-mとテン-aの遺伝子解析を行い,その中には乱射に関する研究も含まれていた.
- タンパク質の相互作用,特にTen-mとα-Spectrinの相互作用を研究した.
- 顕微鏡と電気生理学を用いてシナプスの構造と機能を調査した.
主要な成果:
- Ten-aはプレシナプスであり,Ten-mはポストシナプスであり,in vivoで複合体を形成します.
- テヌーリンの干渉は,重度のシナプス喪失,組織障害 (活性ゾーン,放出部位,膜,膀) およびシナプス伝達障害を引き起こした.
- テヌーリンは,シナプス前微小管とシナプス後スペクトルの細胞骨格を破壊する.
- Ten-mはα-スペクトリンと物理的に相互作用する.
- テヌーリンとニューロリギンは,シナプスアセンブリにおけるシネジスティックな役割を担っています.
- 高いTen-mレベルは,運動ニューロンと筋肉の標的選択を調節する.
結論:
- テヌーリンは,一般的なシナプス組織のための重要な双方向のトランスシナプス信号として機能します.
- テヌーリンは細胞骨格を組織し,シナプスの発達に影響を与えます.
- テヌーリンのタンパク質は,神経発達の過程で標的の選択を調節することもできる.
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