Lopresti V, Macagno E R, Levinthal C
Proc Natl Acad Sci U S A. 1974 Apr;71(4):1098-102. doi: 10.1073/pnas.71.4.1098.
We previously showed that the growth of each bundle of eight optic fibers from one ommatidium into the optic lamina of Daphnia occurs in such a way that one of the eight fibers precedes the others into the lamina. The growth cone of this lead fiber makes surface contact with undifferentiated neuroblasts near the midplane. This is followed by a glial-like wrapping of each neuroblast around the fiber. In this report, gap junctions are shown to form for a short period of time between the growing lead fiber and the neuroblast that is wrapping around it. It is proposed that these junctions may represent a morphological correlate of informational exchange between axon and neuroblast. This signaling would then reflect the fact that the sequence of axon proliferation by the lamina neuroblasts within an optic cartrdige, ultimately composed of five lamina neurons and eight optic fibers, parallels the order in which the neuroblasts undergo the wrapping reaction with the lead fiber.
我们之前表明，从一个小眼发出的每束八根视神经纤维向水蚤视神经板的生长方式是，八根纤维中的一根比其他纤维先进入视神经板。这根引导纤维的生长锥与中平面附近未分化的神经母细胞进行表面接触。随后，每个神经母细胞会像神经胶质一样围绕纤维进行包裹。在本报告中，研究显示在生长中的引导纤维和围绕它的神经母细胞之间会在短时间内形成缝隙连接。有人提出，这些连接可能代表轴突与神经母细胞之间信息交换的一种形态学关联。这种信号传导进而反映出这样一个事实，即在一个最终由五个视神经板神经元和八根视神经纤维组成的视小叶内，视神经板神经母细胞的轴突增殖顺序与神经母细胞与引导纤维发生包裹反应的顺序是平行的。
