Signaling molecule helps neurons find their way in the developing brain

Researchers have discovered a molecule secreted by cells in the spinal cord that helps guide axons during the development of the embryo. The finding helps solve the mystery: how do the billions of neurons in the embryo nimbly reposition themselves within the brain and spinal cord, and connect branches to form neural circuits?
 
Working in mice, the researchers identified an axon guidance factor, NELL2, and explained how it makes commissural axons (which connect the two sides of the brain).
 
The findings could help scientists understand what goes wrong in a rare disease called horizontal gaze palsy with progressive scoliosis. People affected by the condition often suffer from abnormal spine curvature, and are unable to move their eyes horizontally from side to side. The study was published Thursday Nov. 19 in the journal Science.