Development of Myelinating Glia: An Overview

Authors

Carlo D Cristobal
Hyun Kyoung Lee

Publication Date

12-1-2022

Journal

Glia

DOI

10.1002/glia.24238

PMID

35785432

PMCID

PMC9561084

PubMedCentral® Posted Date

7-4-2022

PubMedCentral® Full Text Version

Post-print

Published Open-Access

yes

Keywords

Female, Humans, Myelin Sheath, Neuroglia, Peripheral Nervous System, Pregnancy, Schwann Cells, Transcription Factors, CNS and PNS development, myelination, oligodendrocytes, Remak cells, Schwann cells

Abstract

Myelin is essential to nervous system function, playing roles in saltatory conduction and trophic support. Oligodendrocytes (OLs) and Schwann cells (SCs) form myelin in the central and peripheral nervous systems respectively and follow different developmental paths. OLs are neural stem-cell derived and follow an intrinsic developmental program resulting in a largely irreversible differentiation state. During embryonic development, OL precursor cells (OPCs) are produced in distinct waves originating from different locations in the central nervous system, with a subset developing into myelinating OLs. OPCs remain evenly distributed throughout life, providing a population of responsive, multifunctional cells with the capacity to remyelinate after injury. SCs derive from the neural crest, are highly dependent on extrinsic signals, and have plastic differentiation states. SC precursors (SCPs) are produced in early embryonic nerve structures and differentiate into multipotent immature SCs (iSCs), which initiate radial sorting and differentiate into myelinating and non-myelinating SCs. Differentiated SCs retain the capacity to radically change phenotypes in response to external signals, including becoming repair SCs, which drive peripheral regeneration. While several transcription factors and myelin components are common between OLs and SCs, their differentiation mechanisms are highly distinct, owing to their unique lineages and their respective environments. In addition, both OLs and SCs respond to neuronal activity and regulate nervous system output in reciprocal manners, possibly through different pathways. Here, we outline their basic developmental programs, mechanisms regulating their differentiation, and recent advances in the field.