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Updated: Jul 13, 2026

12:53
Electrophysiological Recordings from the Giant Fiber Pathway of D. melanogaster
Published on: January 14, 2011
膀内細胞症は,迅速な中枢神経系のシナプスでダイナミンに依存したGTPの水解を必要とします
Takayuki Yamashita1, Toshihide Hige, Tomoyuki Takahashi
1Department of Neurophysiology, University of Tokyo Graduate School of Medicine, Tokyo 113-0033, Japan.
まとめ
ダイナミン-1は,ヘルドシナプスのカリックスにおける膀内分細胞化に不可欠である. この研究では,ダイナミン-1のGTPase活性が,神経伝達物質の放出後にシナプスベジクルをリサイクルするために重要であることが示されています.
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
- シナプス伝送 シナプス伝送
背景:
- 膀内分細胞症は,エクソサイトーシス後のシナプス膀のリサイクルによってシナプス機能を維持するために重要である.
- 急速な中枢神経系 (CNS) のシナプスにおける内分細胞症の基礎となる分子機構は,まだ完全に理解されていません.
研究 の 目的:
- ヘルド・ターミナルのカリックスにおける膀内細胞症の分子依存性を調査する.
- このシナプスの内細胞経路におけるダイナミン-1の役割を決定する.
主な方法:
- 容量測定は,脳幹のスライスにおけるヘルド末端のカリックスにおける膜動態をモニターするために使用されました.
- ボトリン毒素Eは",キス・アンド・ラン"メカニズムを調査するために使用されました.
- GTPgSまたはダイナミン-1プロリン豊富なドメインペプチドによるプレシナプス負荷は,ダイナミン-1機能を抑制するために使用されました.
主要な成果:
- 以前に"キス・アンド・ラン"として提案された急速容量トランジタは,送信機の解放から独立していることが判明しました.
- 放出に関連した容量変化は10−25秒の内細胞時間常数で衰退した.
- GTPgSまたはペプチドによるダイナミン-1機能の抑制により,エンドサイトーシスが廃止され,使用に依存するエクソサイトーシスの減少につながります.
結論:
- ダイナミン-1は,ヘルド・シナプスのカリックスにおける膀内分細胞化に不可欠である.
- ダイナミン-1のグアノシン・トリフォスファタゼ活動は,内分泌過程において極めて重要です.
- これらの発見は,迅速なCNSシナプスにおけるシナプス膀のリサイクルにおけるダイナミン-1の重要性を強調しています.
関連する概念動画
GTPases and their Regulation
Guanine nucleotide-binding proteins (G-proteins), also known as GTPases, are a superfamily of proteins that regulate many cellular processes, such as cell signaling, vesicular transport, and the regulation of cell shape and motility. Mutation or dysfunction of these proteins can lead to disease. There are around 40,000 known G-proteins that can broadly be classified into two groups ‒ small G-proteins consisting of a single domain and large multi-domain G-proteins.
Large G-proteins, also known...
Large G-proteins, also known...
GPI Anchoring of Proteins in the ER Membrane
GPI-anchoring is a post-translational, reversible protein modification that is ubiquitous in eukaryotes. Such proteins are primarily present on the exoplasmic leaflet of the plasma membrane.
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
GPI-anchor structure
A sequence of 11 enzymatic reactions results in the synthesis of the complete GPI anchor consisting of a hydrophobic and a hydrophilic portion. The hydrophobic portion comprises phosphatidylinositol, while the hydrophilic part comprises polar groups like phosphoethanolamine,...
Cell Motility through Blebbing
Blebs are a type of membrane protrusion formed by the internal hydrostatic pressure of the cytoplasm. Blebs are observed in several cell types, including fibroblasts, immune cells, and single-celled organisms like the amoeba. The primary function of blebs is cell locomotion and apoptosis, but they are also found during necrosis and cell division. The life cycle of a bleb comprises an initiation phase followed by the expansion and retraction phases.
Blebbing Through the Matrix
In multicellular...
Blebbing Through the Matrix
In multicellular...
Activation and Inactivation of G Proteins
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...
G-Protein Gated Ion Channels
GPCRs are primarily responsible for our sense of smell, taste, and vision. The binding of a sensory stimulus activates GPCR to stimulate effector proteins, many of which are ion channels in the sensory organs. GPCRs modulate the opening and closing of the target ion channels either directly by binding them, or by releasing second messengers that activate these channels. As ions move across the membrane, the membrane potential is altered, which induces an appropriate response.
Sensory organs,...
Sensory organs,...
Activation of Integrins
Integrins bind ligands and transmit information from outside the cell to inside or vice-versa through an "outside-in signaling" or "inside-out signaling."
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.
In "outside-in signaling," external factors in the extracellular space bind to exposed ligand binding sites on integrins. This causes the inactive protein to undergo a conformational change to become active. Integrins are often clustered on the cell membrane. Repetitive and regularly spaced ligand binding events provide an effective stimulus.

