Title

Changing Pax6 Expression Correlates with Axon Outgrowth and Restoration of Topography During Optic Nerve Regeneration

Document Type

Journal Article

Faculty

Computing, Health and Science

School

Exercise, Biomedical and Health Science

RAS ID

5176

Comments

This article was originally published as: Rodger, J., King, C., Lukehurst, S., Chen, P., Dunlop, S., Beazley, L., & Ziman, M. R. (2006). Changing Pax6 expression correlates with axon outgrowth and restoration of topography during optic nerve regeneration. Neuroscience, 142(4), 1043-1054. Original article available here

Abstract

Pax6, a member of the highly conserved developmental Pax gene family, plays a crucial role in early eye development and continues to be expressed in adult retinal ganglion cells (RGCs). Here we have used Western blots and immunohistochemistry to investigate the expression of Pax6 in the formation and refinement of topographic projections during optic nerve regeneration in zebrafish and lizard. In zebrafish with natural (12-h light/dark cycle) illumination, Pax6 expression in RGCs was decreased during axon outgrowth and increased during the restoration of the retinotectal map. Rearing fish in stroboscopic illumination to prevent retinotopic refinement resulted in a prolonged decrease in Pax6 levels; return to natural light conditions resulted in map refinement and restoration of normal Pax6 levels. In lizard, RGC axons spontaneously regenerate but remain in a persistent state of regrowth and do not restore topography; visual training during regeneration, however, allows a stabilization of connections and return of topography. Pax6 was persistently decreased in untrained animals but remained increased in trained ones. In both species, changes in expression were not due to cell division or cell death. The results suggest that decreased Pax6 expression is permissive for axon regeneration and extensive searching, while higher levels of Pax6 are associated with restoration of topography.

DOI

10.1016/j.neuroscience.2006.07.057

 

Link to publisher version (DOI)

10.1016/j.neuroscience.2006.07.057