复合素-1通过同时的SNARE和膜相互作用提高了囊泡对接的启动速度
Jiajie Diao1, Daniel J Cipriano, Minglei Zhao
1Departments of Molecular and Cellular Physiology, Neurology and Neurological Sciences, Structural Biology, and Photon Science and Howard Hughes Medical Institute, Stanford University , Stanford, California 94305, United States.
Journal of the American Chemical Society
|October 3, 2013
概括
复合素-1通过与SNARE复合物和膜相互作用,加快了囊泡与血膜的对接. 这一发现澄清了复合素-1的存在.
科学领域:
- 神经科学是一个神经科学.
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 复合素是神经递质释放的关键调节剂.
- 众所周知,复合素-1可以调节自发和引起释放.
- 它在囊泡对接中的确切作用尚不清楚.
研究的目的:
- 为了研究复合素-1对突触囊泡与血膜的对接速度的影响.
- 阐明复合素-1在囊泡对接中的功能背后的分子机制.
主要方法:
- 使用单个囊泡-囊泡显微镜成像.
- 使用含有synaptobrevin-2和synaptotagmin-1的囊泡模仿剂.
- 使用的血模仿剂含有合成素-1A和SNAP-25A.
主要成果:
- 复合素-1显著提高了囊泡和血膜模仿之间的对接的速度.
- 这种增强取决于复合素-1与膜结合的C端域.
- 复合素-1与SNARE复合体结合的核心区域也至关重要.
结论:
- 复合素-1 作为突触囊泡对接的积极调节剂.
- 它的功能涉及通过C端和SNARE复合体通过核心区域进行膜相互作用.
- 这项研究提供了对复合素-1在突触传播中的作用的机制性见解.
相关概念视频
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...
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
Pinching-off of Coated Vesicles
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...
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...
Clathrin Coated Vesicles
Clathrin-coated vesicles use endocytosis to transport receptors and lysosomal hydrolases from the Golgi to the lysosome in the late secretory pathway. Clathrin-mediated endocytosis was the first described endocytic process, and Clathrin-coated vesicles remain one of the most well-studied transport vesicles. The molecular machinery that generates clathrin-coated vesicles comprises over 50 proteins that precisely coordinate vesicle formation. Cell surface receptors concentrated in indented sites...
Assembly of Signaling Complexes
Multiprotein signaling complexes are formed in a dynamic process involving protein-protein interactions at the cytoplasmic domain of transmembrane receptors or enzymatic and non-enzymatic proteins associated with the receptor. These complexes ensure the activation and propagation of intracellular signals that regulate cell functions.
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Interaction domains in cell signaling
Interaction domains recognize exposed features of their binding partners containing post-translationally modified sequences,...
Rab Cascades
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.


