SNAP-25 スプライス・バリエーションとSNAP-23 スプライス・バリエーションによる放出可能な水泡池の差分制御
Jakob B Sørensen1, Gábor Nagy, Frederique Varoqueaux
1Max-Planck-Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany. jsoeren@gwdg.de
Cell
|July 16, 2003
まとめ
SNAP-25変種とSNAP-23を含むさまざまなSNAREタンパク質は,神経エクソサイトーシスを調節する. すべてが膀融合をサポートしていますが,SNAP-25bは,カルシウム誘発の放出のためのプライムされた膀プールを維持するのに最も効果的です.
科学分野:
- 細胞生物学 細胞生物学
- 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.
背景:
- SNARE複合体は,神経分泌細胞におけるカルシウム誘発のエクソサイトーシスに不可欠である.
- 膀融合調節における SNARE アイソフォームとホモログの役割に関する理解は限られている.
研究 の 目的:
- 発達的に調節されたイソフォームと相似性SNARE成分が神経エクソサイトーシスにどのように影響するかを調査する.
- 膀融合の調節におけるSNAP-25a,SNAP-25b,SNAP-23の機能を比較する.
主な方法:
- Snap25 nullマウスのクロマフィン細胞における神経エクソサイトーシスの分析.
- SNAP-25a,SNAP-25b,およびSNAP-23のバリエーションを使用した救助実験.
- 膀ドッキング,プライムされた膀プール,およびカルシウム誘発放出運動の評価.
主要な成果:
- SNAP-25の欠如は,継続的な膀ドッキングにもかかわらず,迅速なカルシウム誘発放出を廃止し,プライムされた膀プールを空にした.
- シングル・フュージョン・イベントは正常な特徴を示したが,SNAP-25.5なしでは,フュージョン・ポールの持続時間が短かった.
- SNAP-25a,SNAP-25b,およびSNAP-23の過剰発現は,SNAP-25bがSNAP-25aよりも大きなプライムプールをサポートし,SNAP-23がプライムされた膀プールをサポートできず,異なるフェノタイプをもたらしました.
結論:
- SNAP-25の変種とSNAP-23を含む代替のSNARE成分は,エクソサイトーシスをサポートすることができます.
- これらのSNAREコンポーネントは,放出のためにプライム状態の膀を安定させる能力において著しく異なる.
さらに関連する動画
関連する概念動画
Overview of Secretory Vesicles
8.9K
Secretory vesicles, also known as dense core vesicles (DCVs), are membrane-bound vesicles that transport secretory proteins, such as hormones or neurotransmitters. Regulated secretory vesicles transport proteins from the trans-Golgi network to the exterior of the cell. Proteins present in regulated secretory vesicles are required to be rapidly exocytosed in large amounts upon a specific stimulus.
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
Various proteins regulate the aggregation of molecules inside the secretory vesicles. Chromogranins...
8.9K
Fusion of Secretory Vesicles with the Plasma Membrane
16.0K
Proteins and neurotransmitters in secretory vesicles can be released from a cell upon vesicle docking, priming, and fusion with the plasma membrane. Vesicles are docked and primed in preparation for the quick exocytosis of their contents in response to a stimulus. The fusion process is mainly carried out by a SNAP Receptor or SNARE complex, consisting of synaptobrevin, syntaxin-1, and SNAP-25.
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
16.0K
Pinching-off of Coated Vesicles
3.2K
Vesicle budding is orchestrated by distinct cytosolic proteins such as adaptor proteins, coat proteins, and GTPases. To initiate vesicle budding, membrane-bending proteins containing crescent-shaped BAR domains bind to the lipid heads in the bilayer and distort the membrane to form a protein-coated vesicle bud. Adaptors proteins such as AP2 for clathrin-coated vesicles can nucleate on the deformed membrane. Finally, coat proteins such as clathrin or COPI and COPII assemble into a coat forming...
3.2K
SNAREs and Membrane Fusion
10.5K
Once a transport vesicle has recognized its target organelle, the vesicular membrane needs to fuse with the target membrane to unload the cargo. Transmembrane proteins called SNAREs present on organelle membranes and their vesicles, mediate vesicle fusion.
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
SNAREs exist in pairs that symmetrically interact and catalyze the fusion of the lipid bilayers in vesicle and target organelle. v-SNARE in the vesicle membrane are single polypeptide chains that bind to a complementary t-SNARE, composed of 2...
10.5K
Vesicular Tubular Clusters
2.5K
After budding out from the ER membrane, some COPII vesicles lose their coat and fuse with one another to form larger vesicles and interconnected tubules called vesicular tubular clusters or VTCs. These clusters constitute a compartment at the ER-Golgi interface known as ERGIC (Endoplasmic Reticulum Golgi Intermediate Compartment). The ERGIC is a mobile membrane-bound cargo transport system that sorts proteins secreted from ER and delivers them to the Golgi.
With the help of motor proteins such...
With the help of motor proteins such...
2.5K
Rab Cascades
2.9K
Rab GTPases act in a regulated cascade during membrane fusion, helping the lipid bilayers mix. The Rab family of proteins are active when bound to GTP, and inactive when bound to GDP. Hence, they act as guanine nucleotide-dependent molecular switches. Rab-GTP recognizes and binds to long or short-range tethering proteins to capture the target vesicle. These tethers coordinate with SNAREs on the vesicle and the target membrane to assemble the trans SNARE complex that locks the mixing bilayers.
2.9K


