在SNARE蛋白分裂后神经递质释放的明显动态变化
Takeshi Sakaba1, Alexander Stein, Reinhard Jahn
1Department of Neurobiology and Department of Membrane Biophysics, Max Planck Institute for Biophysical Chemistry, Göttingen 37077, Germany. tsakaba@gwdg.de
Science (New York, N.Y.)
|July 16, 2005
概括
闭层神经毒素会分裂SNARE蛋白,改变神经递质释放动力学. 不同的毒素对敏感性和囊泡释放有不同的影响,揭示了突触传播中的特定作用.
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:
- 神经递质释放对神经元通信至关重要.
- 这一过程非常依赖于SNARE蛋白 (可溶性N-乙基胺敏感因子附着蛋白受体).
- 密闭性神经毒素被广泛用于剖析SNARE蛋白质的功能.
研究的目的:
- 研究特定的SNARE蛋白在神经递质释放中的不同作用.
- 确定神经毒素对不同SNARE蛋白的分裂如何影响释放动力学和敏感性.
主要方法:
- 使用了来自老鼠的前突触终端的杯子.
- 使用中的直接提高细胞内的度.
- 施用毒素A (BoNT/A),毒素C1 (BoNT/C1) 和毒素 (TeNT) 来分裂特定的SNARE蛋白质.
主要成果:
- 通过BoNT/A切割SNAP-25,显著降低了释放的敏感性.
- 通过BoNT/C1切割合成素和TeNT切割合成素,导致完全或无限地阻断释放,而不会改变剩余的囊泡动力学.
- 当释放被流量刺激时,BoNT/C1和TeNT表现出明显的效果,这表明突触基维因裂变影响道释放合.
结论:
- 不同的SNARE蛋白质在调节神经递质释放的动力学和依赖性方面发挥着不同的作用.
- 显然,Synaptobrevin的功能对于通过道合流入以释放具有竞争力的囊泡至关重要.
- 神经毒素介导的裂变提供了一个强大的工具,以阐明SNARE蛋白在突触传播中的特定贡献.
相关概念视频
01:26Fusion 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...
01:43SNAREs 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...
01:29Excitatory and Inhibitory Effects of Neurotransmitters
When an action potential reaches the presynaptic axon terminal, it releases neurotransmitters from the neuron into the synaptic cleft at a chemical synapse. The released neurotransmitter can be excitatory or inhibitory. The critical criteria commonly used to determine whether a molecule is a neurotransmitter at a chemical synapse are the molecule's presence in the presynaptic neuron. Second, its release is in response to strong presynaptic depolarization. And lastly, the presence of specific...
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
01:29Relaxation of Skeletal Muscles
The period of muscle contraction primarily influences the duration of stimulation at the neuromuscular junction (NMJ), the presence of free calcium ions in the sarcoplasm, and the availability of energy or ATP to support contractions.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.
01:26Chemical Synapses
Chemical synapses are specialized sites between two neurons or between a neuron and a non-neuronal cell like a muscle, glandular or sensory cell.
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...
Because chemical synapses depend on the release of neurotransmitter molecules from synaptic vesicles to pass on their signal, there is an approximately one millisecond delay between when the axon potential reaches the presynaptic terminal and when the neurotransmitter leads to opening of postsynaptic ion channels. Additionally, this signaling is...