Fig. 6: Model of the role of adaxonal myelin proteins CMTM6 and MAG in regulating the diameters of peripheral axons.
From: CMTM6 expressed on the adaxonal Schwann cell surface restricts axonal diameters in peripheral nerves
a, b Compared to wild-type mice (a), the diameters of peripheral axons (light brown) are decreased in the absence of myelin-associated glycoprotein (MAG) (b) (see ref. 14 and Supplementary Fig. 12), which is specifically expressed by Schwann cells (green). This implies that MAG-dependent signaling by Schwann cells increases axonal diameters14. c The diameters of peripheral axons are markedly increased (arrows) when Schwann cells lack CMTM6, indicating that Schwann cells utilize CMTM6 to restrict axonal diameters. d Diameters of peripheral axons are increased (arrows) when Schwann cells lack both MAG and CMTM6, indicating that loss-of-CMTM6-function overrides loss-of-MAG-function regarding axonal diameters. Schwann cells thus regulate the diameters of peripheral axons via adaxonal surface proteins including MAG and CMTM6. Scheme created by Maria A. Eichel with Biorender.com.
