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Ca 2+ activity signatures of myelin sheath formation and growth in vivo.

ABSTRACT: During myelination, individual oligodendrocytes initially over-produce short myelin sheaths, which are either retracted or stabilized. By live-imaging oligodendrocyte Ca2+ activity in vivo, we find that high-amplitude, long-duration Ca2+ transients in sheaths prefigure retractions, mediated by calpain. Following stabilization, myelin sheaths grow along axons, and we find that higher-frequency Ca2+ transient activity in sheaths precedes faster elongation. Our data implicate local Ca2+ signaling in regulating distinct stages of myelination.

SUBMITTER: Baraban M

PROVIDER: S-EPMC5742537 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Ca 2+ activity signatures of myelin sheath formation and growth in vivo.

Baraban Marion M Koudelka Sigrid S Lyons David A DA

Nature neuroscience 20171211 1

During myelination, individual oligodendrocytes initially over-produce short myelin sheaths, which are either retracted or stabilized. By live-imaging oligodendrocyte Ca2+ activity in vivo, we find that high-amplitude, long-duration Ca2+ transients in sheaths prefigure retractions, mediated by calpain. Following stabilization, myelin sheaths grow along axons, and we find that higher-frequency Ca2+ transient activity in sheaths precedes faster elongation. Our data ...[more]

PMID: 29230058

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