中国神经再生研究(英文版) ›› 2015, Vol. 10 ›› Issue (8): 1206-1208.doi: 10.4103/1673-5374.162694

• 观点:神经损伤修复保护与再生 • 上一篇    下一篇

侧枝萌发时神经树突干的局限性调节

  

  • 收稿日期:2015-06-17 出版日期:2015-08-24 发布日期:2015-08-24

Localized regulation of the axon shaft during the emergence of collateral branches

Gianluca Gallo   

  1. Shriners Hospitals Pediatric Research Center, Temple University School of Medicine, Department of Anatomy and Cell Biology,
    Philadelphia, PA, USA
  • Received:2015-06-17 Online:2015-08-24 Published:2015-08-24
  • Contact: Gianluca Gallo, Ph.D., tue86088@temple.edu.
  • Supported by:

    This work has been supported by an NIH award (NS078030) to GG.

摘要:

轴突分枝在轴突的发育及损伤后再生中起着重要的作用。然而,丝足如何在短暂的肌动蛋白细胞骨架的基础上形成稳定的结构,促进分枝持续的增长机制仍未得阐明。在本文中,作者介绍了当前关于轴突侧支形成的研究结果和模型。描述了肌动蛋白在分支从发育到成熟的每一步的事实和假设,包括肌动蛋白形成,微管肌动蛋白的相互作用和微管稳定的信号通路和分子。

Abstract:

The ability of the axon to form de novo collateral branches along its length is fundamental to the establishment of complex patterns of connectivity during development and is also a major response of many axonal populations following injury. The emergence of branches is under both positive and negative control by extracellular signals. How the site of branch formation is determined is a fundamental question regarding the formation of branches. In theory, the whole axon shaft has the potential to give rise to a branch, but yet branches form only at specific sites. This feature of the formation of branches is emphasized by studies in which nerve growth factor (NGF), covalently attached to 10 micron beads, was applied locally along embryonic sensory axons. Although contact of the beads with the axon shaft was able to drive the formation of a branch at the sites of contact, even after 3 hours of continuous contact only 46% of sites gave rise to a branch. Similarly, when NGF is bath applied to cultured sensory neurons, and thus the whole surface of the axon is exposed to NGF, axons usually only generate a maximum of 4-6 branches along the distal 100 microns of the axon, a response that is maximal by 30 min of treatment. Recent work, from our laboratory and others, has begun to shed light on why axons form branches at specific sites.