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Synaptic vesicle release regulates myelin sheath number of individual oligodendrocytes in vivo.

ABSTRACT: The myelination of axons by oligodendrocytes markedly affects CNS function, but how this is regulated by neuronal activity in vivo is not known. We found that blocking synaptic vesicle release impaired CNS myelination by reducing the number of myelin sheaths made by individual oligodendrocytes during their short period of formation. We also found that stimulating neuronal activity increased myelin sheath formation by individual oligodendrocytes. These data indicate that neuronal activity regulates the myelinating capacity of single oligodendrocytes.

SUBMITTER: Mensch S

PROVIDER: S-EPMC4427868 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Synaptic vesicle release regulates myelin sheath number of individual oligodendrocytes in vivo.

Mensch Sigrid S Baraban Marion M Almeida Rafael R Czopka Tim T Ausborn Jessica J El Manira Abdeljabbar A Lyons David A DA

Nature neuroscience 20150406 5

The myelination of axons by oligodendrocytes markedly affects CNS function, but how this is regulated by neuronal activity in vivo is not known. We found that blocking synaptic vesicle release impaired CNS myelination by reducing the number of myelin sheaths made by individual oligodendrocytes during their short period of formation. We also found that stimulating neuronal activity increased myelin sheath formation by individual oligodendrocytes. These data indicate that neuronal activity regulat ...[more]

PMID: 25849985

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Oligodendrocytes express synaptic proteins that modulate myelin sheath formation.

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| S-EPMC6739339 | biostudies-literature

CNS Myelin Sheath Lengths Are an Intrinsic Property of Oligodendrocytes.

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| S-EPMC4580335 | biostudies-literature

Individual oligodendrocytes have only a few hours in which to generate new myelin sheaths in vivo.

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Individual Neuronal Subtypes Exhibit Diversity in CNS Myelination Mediated by Synaptic Vesicle Release.

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SCRAPPER-dependent ubiquitination of active zone protein RIM1 regulates synaptic vesicle release.

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Individual neuronal subtypes control initial myelin sheath growth and stabilization.

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| S-EPMC3821175 | biostudies-literature

Drosophila Synaptotagmin 7 negatively regulates synaptic vesicle release and replenishment in a dosage-dependent manner.

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Myelination induces axonal hotspots of synaptic vesicle fusion that promote sheath growth.

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Evidence That <i>ITPR2</i>-Mediated Intracellular Calcium Release in Oligodendrocytes Regulates the Development of Carbonic Anhydrase II + Type I/II Oligodendrocytes and the Sizes of Myelin Fibers.

Project description:Myelination of neuronal axons in the central nervous system (CNS) by oligodendrocytes (OLs) enables rapid saltatory conductance and axonal integrity, which are crucial for normal brain functioning. Previous studies suggested that different subtypes of oligodendrocytes in the CNS form different types of myelin determined by the diameter of axons in the unit. However, the molecular mechanisms underlying the developmental association of different types of oligodendrocytes with different fiber sizes remain elusive. In the present study, we present the evidence that the intracellular Ca2+ release channel associated receptor (Itpr2) contributes to this developmental process. During early development, Itpr2 is selectively up-regulated in oligodendrocytes coinciding with the initiation of myelination. Functional analyses in both conventional and conditional Itpr2 mutant mice revealed that Itpr2 deficiency causes a developmental delay of OL differentiation, resulting in an increased percentage of CAII+ type I/II OLs which prefer to myelinate small-diameter axons in the CNS. The increased percentage of small caliber myelinated axons leads to an abnormal compound action potentials (CAP) in the optic nerves. Together, these findings revealed a previously unrecognized role for Itpr2-mediated calcium signaling in regulating the development of different types of oligodendrocytes.

| S-EPMC8492996 | biostudies-literature

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