EphB signaling regulates target innervation in the developing and deafferented auditory brainstem.
EphB signaling regulates target innervation in the developing and deafferented auditory brainstem.
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EphB 信号传导调节发育中和传入神经缺失的听觉脑干的目标神经支配。
DOI：
10.1002/dneu.20990
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发表时间：
2012
影响因子：
3
通讯作者：
Cramer,KarinaS
中科院分区：
文献类型：
--
作者：
Nakamura,PaulA;Hsieh,CandaceY;Cramer,KarinaS
听觉脑干连接的精确性是声音定位的基础。哺乳动物的耳蜗活动通过听神经传递到脑干的腹侧耳蜗核（VCN）。VCN球状丛状细胞投射到对侧梯形体（MNTB）的内侧核，在那里，特殊的轴突终末（Held的萼）包裹着MNTB的主要神经元。VCN - MNTB通路是用于计算用于定位声音的耳间强度差异的电路的重要组成部分。在出生后早期发育过程中，当一只耳朵的输入被移除时，听觉脑干电路显示出强大的解剖可塑性。控制听觉脑干回路发育的分子机制以及这些通路的发育可塑性尚不清楚。在这项研究中，我们研究了EphB信号在VCN - MNTB投射的发展和单侧神经分化后该通路重组中的作用。我们发现EphB2和EphB3反向信号对于VCN到MNTB的正常投射发育至关重要，但成功的电路组装很可能依赖于许多EphB蛋白的协调功能。我们还发现，在单侧神经分化后，ephrin‐B反向信号抑制诱导的对同侧MNTB的预测，这表明类似的机制调节着这两个过程。©2011 Wiley期刊公司Develop Neurobiol, 2012
Precision in auditory brainstem connectivity underlies sound localization. Cochlear activity is transmitted to the ventral cochlear nucleus (VCN) in the mammalian brainstem via the auditory nerve. VCN globular bushy cells project to the contralateral medial nucleus of the trapezoid body (MNTB), where specialized axons terminals, the calyces of Held, encapsulate MNTB principal neurons. The VCN‐MNTB pathway is an essential component of the circuitry used to compute interaural intensity differences that are used for localizing sounds. When input from one ear is removed during early postnatal development, auditory brainstem circuitry displays robust anatomical plasticity. The molecular mechanisms that control the development of auditory brainstem circuitry and the developmental plasticity of these pathways are poorly understood. In this study we examined the role of EphB signaling in the development of the VCN‐MNTB projection and in the reorganization of this pathway after unilateral deafferentation. We found that EphB2 and EphB3 reverse signaling are critical for the normal development of the projection from VCN to MNTB, but that successful circuit assembly most likely relies upon the coordinated function of many EphB proteins. We have also found that ephrin‐B reverse signaling repels induced projections to the ipsilateral MNTB after unilateral deafferentation, suggesting that similar mechanisms regulate these two processes. © 2011 Wiley Periodicals, Inc. Develop Neurobiol, 2012