Int. J. Dev. Biol. 64: 353 - 366 (2020)

https://doi.org/10.1387/ijdb.190130sg

Vol 64, Issue 4-5-6

Special Issue: Developmental Biology in India - Second Part

Neural cells and their progenitors in regenerating zebrafish spinal cord

Published: 23 June 2020

Subhra Prakash Hui¹, Tapas Chandra Nag² and Sukla Ghosh*^,1

¹Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India and ²Department of Anatomy, All India Institute of Medical Sciences, New Delhi, India

Abstract

The zebrafish (Danio rerio), among all amniotes is emerging as a powerful model to study vertebrate organogenesis and regeneration. In contrast to mammals, the adult zebrafish is capable of regenerating damaged axonal tracts; it can replace neurons and glia lost after spinal cord injury (SCI) and functionally recover. In the present paper, we report ultrastructural and cell biological analyses of regeneration processes after SCI. We have focused on event specific analyses of spinal cord regeneration involving different neuronal and glial cell progenitors, such as radial glia, oligodendrocyte progenitors (OPC), and Schwann cells. While comparing the different events, we frequently refer to previous ultrastructural analyses of central nervous system (CNS) injury in higher vertebrates. Our data show (a) the cellular events following injury, such as cell death and proliferation; (b) demyelination and remyelination followed by target innervation and regeneration of synaptic junctions and c) the existence of different progenitors and their roles during regeneration. The present ultrastructural analysis corroborates the cellular basis of regeneration in the zebrafish spinal cord and confirms the presence of both neuronal and different glial progenitors.

Keywords

regeneration, spinal cord, zebrafish, astroglia, neural progenitor