Nakamoto M, Cheng H J, Friedman G C, McLaughlin T, Hansen M J, Yoon C H, O'Leary D D, Flanagan J G
Department of Cell Biology Harvard Medical School Boston, Massachusetts 02115, USA.
Cell. 1996 Sep 6;86(5):755-66. doi: 10.1016/s0092-8674(00)80150-6.
Topographic maps, which maintain the spatial order of neurons in the order of their axonal connections, are found throughout the nervous system. In the visual retinotectal projection, ELF-1, a ligand in the tectum, and its receptors in the retina show complementary gradients in expression and binding, indicating they may be positional labels for map development. Here we show that ELF-1 acts as a repellent axon guidance factor in vitro. In vivo, when the tectal ELF-1 pattern is modified by retroviral overexpression, retinal axons avoid ectopic ELF-1 patches and map to abnormally anterior positions. All these effects were seen on axons from temporal but not nasal retina, indicating that ELF-1 could determine nasal versus temporal retinotectal specificity, and providing a direct demonstration of a cell recognition molecule with topographically specific effects on neural map development.
拓扑图按照神经元轴突连接的顺序维持神经元的空间顺序，在整个神经系统中都能找到。在视觉视网膜顶盖投射中，顶盖中的一种配体ELF-1及其在视网膜中的受体在表达和结合上呈现互补梯度，表明它们可能是拓扑图发育的位置标记。在这里，我们表明ELF-1在体外作为一种排斥性轴突导向因子起作用。在体内，当通过逆转录病毒过表达改变顶盖ELF-1模式时，视网膜轴突避开异位的ELF-1斑块并映射到异常靠前的位置。所有这些效应都在来自颞侧而非鼻侧视网膜的轴突上观察到，表明ELF-1可以决定鼻侧与颞侧视网膜顶盖特异性，并直接证明了一种对神经拓扑图发育具有拓扑特异性作用的细胞识别分子。
