神经元SNARE复合体的螺旋延伸进入膜
Alexander Stein1, Gert Weber, Markus C Wahl
1Department of Neurobiology, Max Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany.
Nature
|July 3, 2009
概括
这项研究揭示了SNARE蛋白质如何组装以驱动神经传递中的膜融合. 这种详细的结构分析表明,SNARE最终组装阶段与膜融合直接相关.
科学领域:
- 分子生物学分子生物学
- 神经科学是一个神经科学.
- 结构生物学 结构生物学
背景情况:
- 神经传递涉及突触囊泡与神经细胞膜融合,释放神经递质.
- 这种融合过程是由SNARE (可溶性N-乙基胺敏感因子附着蛋白受体) 蛋白质的组装介导的.
- 在真核细胞分泌和内细胞通路中,SNARE对于膜融合至关重要.
研究的目的:
- 阐明神经元SNARE复合组合的结构基础及其与膜融合的关系.
- 为了研究从SNARE组装到膜合并的能量传输机制.
- 为了确定SNARE组件是否与化过程具有构造上的联系.
主要方法:
- 使用X射线晶体学来确定神经元SNARE复合物的结构.
- 这项研究分析了由老鼠合成素1A,SNAP-25和synaptobrevin 2组成的复合物.
- 获得了高分辨率 (3.4 A) 的结构数据,包括碳氧终端链接器和跨膜区域.
主要成果:
- X射线结构显示,SNARE组件延伸到已知的核心复合体之外,形成一个连续的螺旋捆.
- 这种连续捆绑通过链接区域内的特定侧链相互作用进一步稳定.
- 结果表明,整个SNARE组装过程与膜合并直接结合.
结论:
- SNARE复合组装的最后阶段与膜融合有关.
- 了解这种合提供了关于神经递质释放的精确机制的见解.
- 这项研究提高了我们对控制神经元膜动态的分子机械的了解.
相关概念视频
SNAREs and Membrane Fusion
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...
Fusion of Secretory Vesicles with the Plasma Membrane
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...
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Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
Sec61 protein conducting channel
In eukaryotes, the translocon complex comprises a core heterotrimeric translocator channel called the Sec61 complex. This channel includes three transmembrane proteins, Sec61α, Sec61β, and Sec61γ, and is the largest subunit of the translocon complex.
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Their main function is to guide migrating cells during normal tissue morphogenesis or cancer metastasis by recognizing and making initial contacts with the extracellular matrix. However, they can also act as stationary cell anchors or help to establish communication...
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Tail-anchored, or TA, proteins are estimated to make up to 3-5% of membrane proteins found in the eukaryotic cell. Such proteins have a single transmembrane domain located approximately 30 amino acid residues upstream from the C-terminal end. As a result, the signal recognition particle (SRP) cannot guide a TA protein to the ER membrane for cotranslational insertion. Hence, they are integrated into the ER membrane post-translationally using their C-terminal end as the anchor. TA proteins...
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
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Blebbing Through the Matrix
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