在突触终端中突触囊泡融合和膜检索的动力学
1Department of Neurobiology and Behavior, State University of New York, Stony Brook 11794-5230.
Nature
|February 24, 1994
概括
这项研究揭示了神经元外细胞分裂需要高水平,并迅速发生,具有快速的膜检索. 这些发现突显了突触终端在神经递质释放中的专门功能.
科学领域:
- 神经科学是一个神经科学.
- 细胞生物学 细胞生物学
- 生物物理学的生物物理.
背景情况:
- 神经元的通信依赖于在突触处的依赖的外细胞形成.
- 了解这个过程的动力学和依赖性至关重要.
研究的目的:
- 为了研究金鱼视网膜双极神经元终端中异细胞分裂的动力学和依赖性.
- 在前突触终端分泌后的膜检索的特征.
主要方法:
- 同时进行补丁,指标染料和时间解析电容测量.
- 利用金鱼双极神经元的巨大突触终端.
主要成果:
- 细胞外发生的速度很快 (大约. 一万个囊泡/秒) 由电流驱动.
- 当地水平超过50微米是分泌所必需的.
- 观察到膜检索的两个组成部分:快速 (2秒) 和缓慢 (30秒) 的时间常数.
结论:
- 脊椎动物中枢神经系统的神经元分泌是不同的,这是由于迅速的囊泡融合,高需求和快速的膜检索.
- 这些特征突显了突触终端的专业化,以有效释放神经递质.
相关概念视频
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In 1993, Jim Rothman proposed that the antiparallel pairing of vesicular and transmembrane SNAREs, or...
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Pinching-off of Coated Vesicles
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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.
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Vesicular Tubular Clusters
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...
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Chemical 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...
Chemical 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...
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