Without gap junctions, neurons (green) fail to migrate (left). Migration is restored (right) by junctions that adhere but have a closed pore.
KRIEGSTEIN/MACMILLAN
Although they're famous for relaying small signaling molecules such as ions and ATP, gap junctions also display some sticky behavior: they form through the adhesion of two aligned hemichannels on adjacent cells. And yet, says Kriegstein, “an adhesive function for gap junctions has been overlooked.”
Brain cells of mice lacking a gap junction subunit called connexin43 have developmental migration delays in vivo. The defects have been assumed to be caused by faulty intercellular communications.
Kriegstein's group was also interested in migrating brain cells—in particular, radial glial cells, which give birth to neurons that migrate outwards,...
