Data on the effect of knockout of neruregulin-1 type III on Remak bundle structure

Schwann cells in the peripheral nervous system wrap around large diameter axons to form the myelin sheath, that contains one axon. Schwann cells also wrap around small diameter axons to form the Remak bundle, that contains many axons. Neuregulin-1 (NRG1) type III binds Schwann cell plasma membrane ErbB2/3 receptor to regulate morphological changes of Schwann cells. Herein we provide the data on the effect of NRG1 type III knockout (Miyamoto et al., 2017) [1] on the Remak bundle structure. Since complete knockout mice of NRG1type III are embryonically lethal, we have usedNRG1type III (+/−) mice's sciatic nerves in these experiments.


a b s t r a c t
Schwann cells in the peripheral nervous system wrap around large diameter axons to form the myelin sheath, that contains one axon. Schwann cells also wrap around small diameter axons to form the Remak bundle, that contains many axons. Neuregulin-1 (NRG1) type III binds Schwann cell plasma membrane ErbB2/3 receptor to regulate morphological changes of Schwann cells. Herein we provide the data on the effect of NRG1 type III knockout (Miyamoto et al., 2017)

Value of the data
This data set is of value to the scientific community to need the information for the biological effect of a growth factor, especially one in the nervous system.
The data allow us to promote our understanding of how a growth factor plays a role in forming the peripheral nervous system.

Data
The data shared in this article provide electron microscopic analyses of Remak bundles in the peripheral nervous system [2,3]. Schwann cells surround the axons with less than 1 μm of diameters to form Remak bundle. Immunoblotting confirmed that NRG1 type III knockout mice (þ/−) [1] exhibit less expression of NRG1 type III in sciatic nerves (Fig. 1). The length of axon diameters in Remak bundles was comparable in NRG1 type III knockout mice and littermate controls (Figs. 2 and 3). On the other hand, NRG1 type III knockout mice exhibited more numbers of axons in Remak bundles than the controls (Figs. 2 and 4). Also, knockout mice exhibited short distance between an axon and a neighboring axon, comparing with the controls (Figs. 2 and 5).

Electron microscopy
Sciatic nerves were fixed with 2% paraformaldehyde and 2% glutaraldehyde in 0.1% cacodylate buffer. The tissues were post fixed with buffered 2% osmium tetroxide, dehydrated with an ethanol gradient, treated with acetone, and embedded in epoxy resin. Ultrathin sections of cross sections were stained with uranyl acetate and lead citrate. They were observed and photographed with Hitachi electron microscopes [1,4].