Lopresti V, Macagno E R, Levinthal C
Proc Natl Acad Sci U S A. 1973 Feb;70(2):433-7. doi: 10.1073/pnas.70.2.433.
Some details of the growth and initial cellular interactions of optic nerve axons were examined in a parthenogenetic clone of Daphnia magna. Results are summarized as follows: (i) the final structure of the optic lamina is dependent upon interactions between growing optic nerve fibers and optic lamina neuroblasts closest to the midplane of the animal, which trigger the morphological differentiation of the neuroblasts; the specificity of connections is achieved by well-defined sequences of cell migration in the ganglion; (ii) only one of the eight optic nerve axons growing back from each ommatidium in the eye possesses a structure similar to the growth cones seen on termini of nerve fibers growing in vitro; and (iii) undifferentiated neuroblasts in the ganglion react to surface contact by this "lead axon" by enveloping the axon in a glial-like relationship.
在大型溞的孤雌生殖克隆体中研究了视神经轴突生长和初始细胞相互作用的一些细节。结果总结如下：(i)视叶的最终结构取决于生长中的视神经纤维与最靠近动物中平面的视叶神经母细胞之间的相互作用，这种相互作用触发神经母细胞的形态分化；连接的特异性通过神经节中明确的细胞迁移序列实现；(ii)从眼中每个小眼向后生长的八条视神经轴突中只有一条具有类似于体外生长的神经纤维末端所见生长锥的结构；(iii)神经节中未分化的神经母细胞通过以神经胶质样关系包裹轴突来对这条“引导轴突”的表面接触做出反应。
