roundabout homolog 2

ROBO2 belongs to the ROBO family. Members of the ROBO family are a group of highly conserved transmembrane glycoproteins that make up a small subgroup of the immunoglobulin (Ig) superfamily. They are best known for their roles as receptors for the Slit family of repellent axon guidance cues. In structure, ROBOs are characterized by five C2-type Ig-like repeats, three fibronectin type III domains, a transmembrane region, and an intracellular domain with three (ROBO3) or four (ROBO1, 2) CC (conserved cytoplasmic) motifs. ROBO2 is a receptor for SLIT2, and probably SLIT1, which are thought to act as molecular guidance cue in cellular migration, including axonal navigation at the ventral midline of the neural tube and projection of axons to different regions during neuronal development. ROBO2 also abrogates SLIT-ROBO signaling in vitro.

Roundabout homolog 4(ROBO4) contains 2 fibronectin type-III domains, 2 Ig-like C2-type (immunoglobulin-like) domains and belongs to the immunoglobulin superfamily.The protein is a receptor for slit proteins, at least for SLIT2, and seems to be involved in angiogenesis and vascular patterning. ROBO4 may mediate the inhibition of primary endothelial cell migration by Slit proteins.