Krox-20 controls myelination in the peripheral nervous system

@article{Topilko1994Krox20CM,
  title={Krox-20 controls myelination in the peripheral nervous system},
  author={Piotr Topilko and Sylvie Schneider-Maunoury and Giovanni Levi and Anne Baron-Van Evercooren and Amina Ben Younes Chennoufi and Tania Seitanidou and Charles Babinet and Patrick Charnay},
  journal={Nature},
  year={1994},
  volume={371},
  pages={796-799}
}
THE molecular mechanisms controlling the process of myelination by Schwann cells remain elusive, despite recent progress in the identification and characterization of genes encoding myelin components (reviewed in ref. 1). We have created a null allele in the mouse Krox-20 gene, which encodes a zinc-finger transcription factor2,3, by in-frame insertion of the Escherichia coli lacZ gene, and have shown that hindbrain segmentation is affected in Krox-20−/− embryos4. We demonstrate here that Krox… 

Peripheral Myelin Maintenance Is a Dynamic Process Requiring Constant Krox20 Expression

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New insights into signaling during myelination in zebrafish.

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Establishment of myelinating schwann cells and barrier integrity between central and peripheral nervous systems depend on Sox10

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Control of myelination in Schwann cells: a Krox20 cis‐regulatory element integrates Oct6, Brn2 and Sox10 activities

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References

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Compact myelin exists in the absence of basic protein in the shiverer mutant mouse

The shiverer mouse is unique in showing a striking alteration in myelin protein composition that does not significantly affect the gross morphology and lamellar organisation of the myelin sheath, and this results question the proposed role of basic proteins15–19 in Myelin as ‘structural cement’.

Myelination in the absence of myelin-associated glycoprotein

It is indicated that MAG is necessary for maintenance of the cytoplasmic collar and periaxonal space of myelinated fibres and not critical for myelin formation.

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Distribution of the myelin-associated glycoprotein and P0 protein during myelin compaction in quaking mouse peripheral nerve

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The results indicated that conversion of mesaxon membranes to compact myelin involves the insertion of P0 protein into and the removal of the myelin-associated glycoprotein from mesXon membranes.

Immunocytochemical studies of quaking mice support a role for the myelin-associated glycoprotein in forming and maintaining the periaxonal space and periaxonal cytoplasmic collar of myelinating Schwann cells

The immunocytochemical localization of MAG is determined in the L4 ventral roots from 11-mo-old quaking mice and it is hypothesized that MAG plays a structural role in forming and maintaining contact between myelinating Schwann cells and the axon and maintaining the Schwann cell periaxonal cytoplasmic collar of myelinated fibers.

Schwann cells depleted of galactocerebroside express myelin‐associated glycoprotein and initiate but do not continue the process of myelination

Two peripheral myelin components, galactocerebroside (GalC) and myelin‐associated glycoprotein (MAG), are known to be expressed early in Schwann cell differentiation, prior to the formation of

Presence of the myelin-associated glycoprotein correlates with alterations in the periodicity of peripheral myelin

It is proposed that MAG plays a role in maintaining the periaxonal space, Schmidt-Lantermann incisures, paranodal myelin loops, and outer mesaxon by preventing "complete" compaction of Schwann cell and myelin membranes.