Department of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Science. 2010 Jun 4;328(5983):1285-8. doi: 10.1126/science.1189095. Epub 2010 May 6.
The mechanisms controlling the formation and maintenance of neuronal trees are poorly understood. We examined the dynamic development of two arborized mechanoreceptor neurons (PVDs) required for reception of strong mechanical stimuli in Caenorhabditis elegans. The PVDs elaborated dendritic trees comprising structural units we call "menorahs." We studied how the number, structure, and function of menorahs were maintained. EFF-1, an essential protein mediating cell fusion, acted autonomously in the PVDs to trim developing menorahs. eff-1 mutants displayed hyperbranched, disorganized menorahs. Overexpression of EFF-1 in the PVD reduced branching. Neuronal pruning appeared to involve EFF-1-dependent branch retraction and neurite-neurite autofusion. Thus, EFF-1 activities may act as a quality control mechanism during the sculpting of dendritic trees.
神经元树突的形成和维持的机制还不清楚。我们研究了秀丽隐杆线虫中接收强机械刺激所必需的两个树突状机械感受器神经元(PVDs)的动态发育。PVDs 形成了由我们称之为“烛台”的结构单元组成的树突。我们研究了烛台的数量、结构和功能是如何维持的。EFF-1 是一种介导细胞融合的必需蛋白,它在 PVDs 中自主作用,修剪正在发育的烛台。eff-1 突变体显示出过度分支、紊乱的烛台。EFF-1 在 PVD 中的过表达减少了分支。神经元修剪似乎涉及 EFF-1 依赖性的分支回缩和神经元-神经元自发融合。因此,EFF-1 的活性可能在树突的塑造过程中充当质量控制机制。