Gao F B, Kohwi M, Brenman J E, Jan L Y, Jan Y N
Howard Hughes Medical Institute, Department of Physiology, University of California, San Francisco 94143, USA.
Neuron. 2000 Oct;28(1):91-101. doi: 10.1016/s0896-6273(00)00088-x.
Neurons elaborate dendrites with stereotypic branching patterns, thereby defining their receptive fields. These branching patterns may arise from properties intrinsic to the neurons or competition between neighboring neurons. Genetic and laser ablation studies reported here reveal that different multiple dendritic neurons in the same dorsal cluster in the Drosophila embryonic PNS do not compete with one another for dendritic fields. In contrast, when dendrites from homologous neurons in the two hemisegments meet at the dorsal midline in larval stages, they appear to repel each other. The formation of normal dendritic fields and the competition between dendrites of homologous neurons require the proper expression level of Flamingo, a G protein-coupled receptor-like protein, in embryonic neurons. Whereas Flamingo functions downstream of Frizzled in specifying planar polarity, Flamingo-dependent dendritic outgrowth is independent of Frizzled.
神经元形成具有刻板分支模式的树突，从而确定其感受野。这些分支模式可能源于神经元固有的特性或相邻神经元之间的竞争。此处报道的基因和激光消融研究表明，果蝇胚胎期外周神经系统同一背侧簇中的不同多树突神经元不会相互竞争树突野。相反，在幼虫阶段，来自两个半体节中同源神经元的树突在背中线相遇时，它们似乎会相互排斥。正常树突野的形成以及同源神经元树突之间的竞争需要胚胎神经元中Flamingo（一种G蛋白偶联受体样蛋白）的适当表达水平。虽然Flamingo在指定平面极性方面在Frizzled下游起作用，但Flamingo依赖的树突生长独立于Frizzled。
