相关实验视频
Updated: Jul 8, 2026

06:55
Microfluidics-Assisted Selective Depolarization of Axonal Mitochondria
Published on: August 4, 2022
合成林对轴突线粒体的对接控制了它们的移动性,并影响了短期的促进作用
Jian-Sheng Kang1, Jin-Hua Tian, Ping-Yue Pan
1Synaptic Function Section, The Porter Neuroscience Research Center, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Building 35, Room 3B203, 35 Convent Drive, Bethesda, MD 20892, USA.
Cell
|January 15, 2008
概括
合成素 (SNPH) 将线粒体固定在轴突中,控制它们的静止阶段. 删除SNPH基因增加了线粒体的移动性,并影响了突触功能,揭示了神经元健康的关键机制.
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
- 线粒体动力学的动力学
背景情况:
- 线粒体分布对于神经元功能至关重要,特别是在轴突和突触中.
- 虽然一些轴突线粒体是移动的,但控制它们的静止定 (对接) 的机制在很大程度上是未知的.
- 了解线粒体对接是理解神经元能量供应和功能的关键.
研究的目的:
- 研究控制神经元轴突内的线粒体对接的分子机制.
- 确定轴突向合成蛋白 (SNPH) 在调节线粒体的移动性和分布方面的作用.
- 评估改变线粒体对接对突触功能的生理影响.
主要方法:
- 研究了合成素 (SNPH) 和微管在控制线粒体局部化的相互作用.
- 利用SNPH的外源和内源表达来研究其对轴突线粒体移动性的影响.
- 生成并分析了snph基因淘汰赛小鼠,以评估线粒体分布和突触生理学的体内影响.
- 通过重新引入snph基因到突变神经元中进行了救援实验.
主要成果:
- 合成蛋白 (SNPH) 直接介导线粒体对接到轴突内的微管,减少线粒体的移动性.
- 删除snph基因显著增加了移动轴突线粒体的比例,并减少了线粒体密度.
- 突变SNPH神经元显示增强的短期促进,与改变了前突触终端的信号.
- 重新引入snph基因完全挽救了突变神经元中观察到的突触表型.
结论:
- 合成素 (SNPH) 作为轴突中的线粒体的关键分子,调节它们的静止状态.
- 通过SNPH介导的线粒体对接对于维持正常的线粒体密度和突触功能至关重要.
- 这项研究阐明了一种控制轴突线粒体动态的关键机制,对神经元生理学有重大影响.
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...
Assembly of Complex Microtubule Structures
Complex microtubule structures are present in resting cells and in dividing cells. In resting cells, they are responsible for maintaining the cellular architecture, tracks for intracellular transport, positioning of organelles, assembly of cilia and flagella. They mediate the bipolar spindle assembly for chromosomal segregation and positioning of the cell division plate in dividing cells. The formation of microtubule complex structures depends on the cell type, cell stage, and cell function.
The Movement of Organelles and Vesicles
In eukaryotic cells, cytoskeletal filaments such as actin, microtubules, and intermediate filaments form a mesh-like cytoskeletal network. These filaments serve as tracks for transporting cellular cargo. Specialized motor proteins use the chemical energy stored in adenosine triphosphate (ATP) for this transport. During interphase, microtubules are polarized, with the plus-end towards the cell periphery and the minus-end towards the cell center. Two microtubule-associated motor proteins,...
Neurons: The Axon
Axons are long, cytoplasmic processes of nerve cells capable of propagating electrical impulses known as action potentials. The cytoplasm or axoplasm of an axon contains neurofibrils, neurotubules, small vesicles, lysosomes, mitochondria, and various enzymes, all encased within the axolemma, the plasma membrane of the axon.
The axon attaches to the cell body at a cone-shaped elevation called the axon hillock. The initial part of the axon, closest to the hillock, is known as the initial segment.
The axon attaches to the cell body at a cone-shaped elevation called the axon hillock. The initial part of the axon, closest to the hillock, is known as the initial segment.
Translocation of Proteins into the Mitochondria
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Microtubule Associated Motor Proteins
Eukaryotic cells have different motor proteins for transporting various cargo within the cell. These motor proteins differ based on the filament they associate with, the direction they move within the cell, and the type of cargo they transport. Motor proteins that associate with microtubules are known as microtubule-associated motor proteins. There are two families of microtubule-associated motor proteins —Kinesins and Dyneins. Both these proteins assist in the transport of cellular cargos...
