How the lateral line gets its glia.

During development, the numbers and positions of neurons and glial cells must become precisely matched. A recent study has addressed how the zebrafish lateral line nerve matches up with its glia. Using elegant two-color time-lapse imaging, the authors showed that migrating glia track along the axons precisely and very closely. Combined genetic and embryonic perturbations showed that glia require axons for migration, but not vice versa; however, glia are later required for proper maintenance of axonal fasciculation.