Slit (gene)

Slit refers to a family of related genes which encode a corresponding set of secreted proteins, also collectively referred to as Slit. The ventral midline of the central nervous system is a key place where axons can either decide to cross and laterally project or stay on the same side of the brain. The main function of Slit proteins is to act as midline repellents, preventing the crossing of longitudinal axons through the midline of the central nervous system of most bilaterian animal species, including mice, chickens, humans, insects, nematode worms and planarians. It also prevents the recrossing of commissural axons. Its canonical receptor is Robo but it may have other receptors. The Slit protein is produced and secreted by cells within the floor plate (in vertebrates) or by midline glia (in insects) and diffuses outward. Slit/Robo signaling is important in pioneer axon guidance.