兰维尔节点的质膜可以防止神经元的外生长
Jeffrey K Huang1, Greg R Phillips, Alejandro D Roth
1Fishberg Department of Neuroscience, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029, USA.
Science (New York, N.Y.)
|November 19, 2005
概括
来自哺乳动物中枢神经系统 (CNS) 的节点膜抑制神经元外生长. 氧基细胞髓糖蛋白 (OMgp) 围绕着中枢神经系统节点,稳定它们,并防止轴突发芽.
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
- 分子生物学分子生物学
背景情况:
- 兰维尔节点是重要的,有规律的间隔,在髓轴突沿线的非髓细分.
- 节点膜和相关分子在中枢神经系统 (CNS) 内调节轴突生长中的特定作用仍然不完全理解.
研究的目的:
- 研究哺乳动物中枢神经系统结节膜在调节神经元外生长中的作用.
- 为了识别影响轴突生长的结节膜内的分子,并阐明它们的定位和功能.
主要方法:
- 从哺乳动物中枢神经系统中分离结节膜.
- 使用培养神经元进行神经元外生长测定.
- 蛋白质组分析以识别结节膜内的蛋白质.
- 在大鼠脊髓中对寡头细胞髓糖蛋白 (OMgp) 的免疫组合化学定位.
- 在OMgp-null小鼠中分析中枢神经系统节点和轴突发芽.
主要成果:
- 从哺乳动物中枢神经系统中分离出来的节点膜限制了培养神经元的神经元外生.
- 蛋白质组学分析确定了寡头细胞髓糖蛋白 (OMgp) 作为神经元外生长的关键抑制剂.
- OMgp局部存在于形成中枢神经系统节点周围环状的寡类细胞中,而不是紧的髓.
- 没有OMgp的小鼠表现出异常宽的中枢神经系统节点和附带芽.
结论:
- 中枢神经系统中OMgp表达细胞的节点封闭在稳定Ranvier节点方面发挥着至关重要的作用.
- 这种封闭机制可以防止异常的轴突芽,从而保持神经元的完整性.
- OMgp是中枢神经系统中轴突结构和生长的关键调节者.
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