Garriga G, Desai C, Horvitz H R
Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge 02139.
Development. 1993 Mar;117(3):1071-87. doi: 10.1242/dev.117.3.1071.
The two serotonergic HSN motor neurons of the nematode Caenorhabditis elegans innervate the vulval muscles and stimulate egg laying by hermaphrodites. By analyzing mutant and laser-operated animals, we find that both epithelial cells of the developing vulva and axons of the ventral nerve cord are required for HSN axonal guidance. Vulval precursor cells help guide the growth cone of the emerging HSN axon to the ventral nerve cord. Vulval cells also cause the two HSN axons to join the ventral nerve cord in two separate fascicles and to defasciculate from the ventral nerve cord and branch at the vulva. The axons of either the PVP or PVQ neurons are also necessary for the HSN axons to run in two separate fascicles within the ventral nerve cord. Our observations indicate that the outgrowth of the HSN axon is controlled in multiple ways by both neuronal and nonneuronal cells.
线虫秀丽隐杆线虫的两个5-羟色胺能HSN运动神经元支配外阴肌肉，并刺激雌雄同体动物产卵。通过分析突变体和激光操作的动物，我们发现发育中的外阴的上皮细胞和腹侧神经索的轴突对于HSN轴突导向都是必需的。外阴前体细胞有助于将新生HSN轴突的生长锥引导至腹侧神经索。外阴细胞还会使两条HSN轴突以两个独立的束状结构加入腹侧神经索，并从腹侧神经索解束并在外阴处分支。PVP或PVQ神经元的轴突对于HSN轴突在腹侧神经索内以两个独立的束状结构运行也是必需的。我们的观察结果表明，HSN轴突的生长受到神经元和非神经元细胞的多种方式控制。
