UNC-6/netrin及其受体UNC-5局部排除了来自树突的前突触成分
Vivian Y Poon1, Matthew P Klassen, Kang Shen
1Neuroscience Program, Stanford University School of Medicine, 300 Pasteur Drive, California 94305, USA.
Nature
|September 9, 2008
概括
细胞外线索,如Netrin和Wnt指导神经元的极性. 这些信号阻止了前突触成分在树突中积累,确保了神经元的正常功能.
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
- 发展生物学 发展生物学
背景情况:
- 神经元极性,对于功能至关重要,被认为是由轴突和树突之间的内在结构差异决定的.
- 细胞外线索在体内建立和维持神经元极性中的作用在很大程度上仍未被探索.
研究的目的:
- 调查细胞外线索在指导神经元中前突触元件的极化局部化中的in vivo作用.
- 为了确定轴突指导线索是否影响突触蛋白质从树突上排斥.
主要方法:
- 利用Caenorhabditis elegans运动神经元DA9作为一个模型系统.
- 研究了轴突指导线索UNC-6/netrin及其受体UNC-5的功能.
- 对unc-6/netrin和unc-5的功能丧失突变进行了分析.
- 研究了子宫外UNC-6/网林表达的影响.
主要成果:
- UNC-6/netrin和UNC-5从DA9树突中积极排除突触囊泡和活性区蛋白.
- 失去了UNC-6/netrin或UNC-5导致了前突触组件错位到DA9树突中.
- 宫外UNC-6/网林表达排除了轴突内的特定亚细胞域的突触.
- 尽管有不同的受体,但netrin的抗synaptogenic活性与LIN-44/Wnt可以互换.
结论:
- 细胞外线索,包括网氨酸和Wnt,在调节前突触成分的偏振分布方面发挥着至关重要的作用.
- 这些线索不仅通过引导轴突导航来建立神经元极性,而且还通过调解突触材料的局部排除来建立神经元极性.
- 神经元极性是通过内在因素和外部信号通路的结合来建立的.
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