Cultures of dissociated DRG neurons and Schwann cells were immunostained for Necl4, and βIII tubulin, MBP or MAG, 6, 10, or 17 days after plating as indicated; myelination was induced with ascorbic acid at day 10. (a–d) Increased labeling of Necl4 at contact sites between Schwann cells and the axons are marked by arrowheads. Inset in (c–d) show higher magnification images of the areas marked with an arrowhead. (e–j) Myelin basic protein (MBP) and myelin–associated glycoprotein (MAG)–positive myelinating Schwann cells (arrowheads) have intense Necl4–immunoreactivity. Scale bar: (a–d) 10 µm; (e–j) 30 µm.