单重组的神经元SNARE复合体在三个不同的阶段拉链
Ying Gao1, Sylvain Zorman, Gregory Gundersen
1Department of Cell Biology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA.
概括
可溶性N-乙基胺胺敏感因子附着蛋白受体 (SNARE) 蛋白质介导膜融合. 这项研究揭示了SNARE组装中的一个关键中间体,表明一个逐步的,不是连续的,拉链过程驱动核聚变.
科学领域:
- 生物化学 生化学
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
背景情况:
- 可溶性N-乙基胺胺敏感因子附着蛋白受体 (SNARE) 蛋白质对于膜融合至关重要.
- 通过拉链机制,SNAREs通过拉链机制组装成一个四螺旋捆.
研究的目的:
- 实时观察和描述SNARE组装中间体.
- 为了阐明SNARE介导的膜融合的逐步机制.
主要方法:
- 在无细胞复制实验中使用光学子.
- 应用外部力来模仿膜排斥和稳定中间体.
主要成果:
- 观察到一个稳定的,半组装的SNARE四螺旋束中间体.
- 证明SNARE拉链通过三个连续的二进制开关发生.
- 量化了核聚变过程中释放的自由能量 (36 k B T).
结论:
- 拉链假设得到了支持,但是在离散的步骤中进行.
- 一个半拉链的中间体在膜融合中起着至关重要的作用.
- 外部施加的力可以稳定并影响SNARE复杂组件.
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...
In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
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,...
Protein Complex Assembly
Proteins can form homomeric complexes with another unit of the same protein or heteromeric complexes with different types. Most protein complexes self-assemble spontaneously via ordered pathways, while some proteins need assembly factors that guide their proper assembly. Despite the crowded intracellular environment, proteins usually interact with their correct partners and form functional complexes.
Many viruses self-assemble into a fully functional unit using the infected host cell to...
Many viruses self-assemble into a fully functional unit using the infected host cell to...
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.


