Insights Into Central Nervous System Glial Cell Formation and Function From Zebrafish.

Sarah A Neely,David A Lyons

doi:10.3389/fcell.2021.754606

Abstract

The term glia describes a heterogenous collection of distinct cell types that make up a large proportion of our nervous system. Although once considered the glue of the nervous system, the study of glial cells has evolved significantly in recent years, with a large body of literature now highlighting their complex and diverse roles in development and throughout life. This progress is due, in part, to advances in animal models in which the molecular and cellular mechanisms of glial cell development and function as well as neuron-glial cell interactions can be directly studied in vivo in real time, in intact neural circuits. In this review we highlight the instrumental role that zebrafish have played as a vertebrate model system for the study of glial cells, and discuss how the experimental advantages of the zebrafish lend themselves to investigate glial cell interactions and diversity. We focus in particular on recent studies that have provided insight into the formation and function of the major glial cell types in the central nervous system in zebrafish.

Highlights

The Importance of Glia originally characterised as bystanders to neuronal function by Virchow in 1846, constituting the “glue” of the nervous system (Somjen, 1988), the possible roles of glia in supporting efficient nervous system function have since been vastly explored
It is well established that glial cells are important throughout life, with recent research highlighting their significant contributions to most aspects of nervous system function (Barres, 2008; Allen and Lyons, 2018)
Since their initial description over a century ago, glial cells have been investigated in many diverse model organisms, each providing distinct strengths, with many aspects of glial biology highly conserved across species from invertebrates to humans (Freeman and Doherty, 2006; Lyons and Talbot, 2015; Shaham, 2015; Zuchero and Barres, 2015; Jäkel and Dimou, 2017; Yildirim et al, 2019)

Summary

Introduction

The Importance of Glia originally characterised as bystanders to neuronal function by Virchow in 1846, constituting the “glue” of the nervous system (Somjen, 1988), the possible roles of glia in supporting efficient nervous system function have since been vastly explored. We focus on the contribution of the zebrafish as a model organism to investigate the development and function of the major glial cell types in the vertebrate central nervous system (CNS), from radial glial cells, Müller glial cells, astrocytes, oligodendrocyte progenitor cells (OPCs) and oligodendrocytes (OLs) through to microglia.

Results

Conclusion