Chemoaffinity in topographic mapping revisited--is it more about fiber-fiber than fiber-target interactions?
Chemoaffinity in topographic mapping revisited--is it more about fiber-fiber than fiber-target interactions?
复制标题
重新审视地形测绘中的化学亲和力——它更多的是纤维与纤维之间的相互作用，而不是纤维与目标之间的相互作用吗？
DOI：
10.1016/j.semcdb.2014.07.010
复制
发表时间：
2014
影响因子：
7.3
通讯作者：
Bastmeyer M
中科院分区：
文献类型：
--
作者：
Weth F;Fiederling F;Gebhardt C;Bastmeyer M
保持相邻关系的两组神经元之间的轴突投射被称为地形图。它们在大脑中无处不在。视网膜顶盖投影的发展，将视网膜输出映射到中脑顶，作为一个模型系统已经研究了几十年。正常视网膜定位的严格精确度推动了化学亲和力假说的提出，该假说认为轴突靶向是基于纤维和靶点之间固定的生化亲和力。然而，此外，主要在20世纪70年代和80年代收集的大量证据表明，这种映射可以以惊人的灵活性调整到各种目标，从而证明了制导过程的非凡健壮性。将肾上腺素和Eph受体识别为潜在的分子线索大多被解释为支持纤维靶标化学亲和力假说，而关于映射稳定性的证据在很大程度上被忽视了。通过对旧数据的重新审视，我们阐明，除了纤维-目标化学亲和力之外，它们还表明存在第二个自主引导影响，我们称之为纤维-纤维化学亲和力。经典皂苷的体外观察表明，这两种影响都是由相反的单功能引导活动组成的。基于分子证据，我们认为这些可能是ePhin/Eph的正向和反向信号，不仅在纤维-靶作用中，而且在纤维-纤维相互作用中。事实上，基于这一假设的计算模型可以调和刚性和弹性地形图似乎相互矛盾的结果。它们支持所提出的节俭而强大的机制，有助于理解强健的轴突地形图质量连接的进化成功。
Axonal projections between two populations of neurons, which preserve neighborhood relationships, are called topographic. They are ubiquitous in the brain. The development of the retinotectal projection, mapping the retinal output onto the roof of the midbrain, has been studied for decades as a model system. The rigid precision of normal retinotopic mapping has prompted the chemoaffinity hypothesis, positing axonal targeting to be based on fixed biochemical affinities between fibers and targets. In addition, however, abundant evidence has been gathered mainly in the 1970s and 80s that the mapping can adjust to variegated targets with stunning flexibility demonstrating the extraordinary robustness of the guidance process. The identification of ephrins and Eph-receptors as the underlying molecular cues has mostly been interpreted as supporting the fiber–target chemoaffinity hypothesis, while the evidence on mapping robustness has largely been neglected. By having a fresh look on the old data, we expound that they indicate, in addition to fiber–target chemoaffinity, the existence of a second autonomous guidance influence, which we call fiber–fiber chemoaffinity. Classicalin vitroobservations suggest both influences be composed of opposing monofunctional guidance activities. Based on the molecular evidence, we propose that those might be ephrin/Eph forward and reverse signaling, not only in fiber–target but also in fiber–fiber interactions. In fact, computational models based on this assumption can reconcile the seemingly conflicting findings on rigid and flexible topographic mapping. Supporting the suggested parsimonious and powerful mechanism, they contribute to an understanding of the evolutionary success of robust topographic mass wiring of axons.
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影响因子：
7.2
作者：
Lisabeth EM;Falivelli G;Pasquale EB
通讯作者：
Pasquale EB
DOI：
--
发表时间：
2019
期刊：
Journal of embryology and experimental morphology
影响因子：
--
作者：
C. Straznicky;R. M. Gaze;M. Keating
通讯作者：
M. Keating
金鱼鼻半视网膜的视觉投影转移到视顶盖的异质喙区。
影响因子：
5.3
作者：
M. Yoon
通讯作者：
M. Yoon
金鱼视网膜顶盖投射中无脉冲活动的压缩和扩张。
DOI：
--
发表时间：
1987
期刊：
Journal of Neurobiology
影响因子：
--
作者：
R. Meyer;L. Wolcott
通讯作者：
L. Wolcott
视神经再生后蝾螈（triturus viridescens）的视觉运动协调
DOI：
--
发表时间：
1943
期刊：
影响因子：
--
作者：
R. Sperry
通讯作者：
R. Sperry