ドロソフィラシナプトタグミンの変異分析は,Ca2+) 活性化された神経伝達物質の放出におけるその重要な役割を果たしていることを示しています
J T Littleton1, M Stern, K Schulze
1Division of Neuroscience, Baylor College of Medicine, Houston, Texas 77030.
Cell
|September 24, 1993
まとめ
シナプトタグミン (syt) は,カルシウムに依存する神経伝達物質の放出に不可欠です. フルーツフライの変異は,筋肉の収縮と誘発された放出を妨害し,自発的な放出は増加し,明確な放出経路を示します.
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.
- 遺伝学 遺伝学とは
背景:
- シナプトタグミン (syt) は,カルシウム (Ca2+) 結合に関与するシナプス胞のタンパク質です.
- SytはCa2+に依存する神経伝達物質の放出を媒介すると仮定されています.
研究 の 目的:
- 神経伝達における in vivo sytの役割を調査する.
- Ca2+依存神経伝達物質の放出における sytの機能を決定するために.
主な方法:
- フルーツハエのシナプトタグミン (syt) 遺伝子の変異を生成した.
- 筋肉の収縮と刺激的交差点ポテンシャル (EJP) を調べることで神経伝達を測定した.
主要な成果:
- 細胞が欠けていた胚は,化が失敗し,筋肉の収縮が調整されていませんでした.
- 変異した幼虫は,異なるCa2+濃度で,誘発されたEJPが著しく減少したことを示した.
- 突発的なミニチュアEJP頻度の増加は,シート変異体で観察されました.
結論:
- ニューロントランスミッター放出のCa2+活性化におけるsytの重要な役割に関するin vivo証拠を提供した.
- 誘発および自発的な神経伝達物質の放出のための明確な経路が示されています.
関連する概念動画
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01:16Calmodulin-dependent Signaling
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01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...