ROBO3

This gene is a member of the Roundabout (ROBO) gene family that controls neurite outgrowth, growth cone guidance, and axon fasciculation. ROBO proteins are a subfamily of the immunoglobulin transmembrane receptor superfamily. SLIT proteins 1-3, a family of secreted chemorepellants, are ligands for ROBO proteins and SLIT/ROBO interactions regulate myogenesis, leukocyte migration, kidney morphogenesis, angiogenesis, and vasculogenesis in addition to neurogenesis. This gene, ROBO3, has a putative extracellular domain with five immunoglobulin (Ig)-like loops and three fibronectin (Fn) type III motifs, a transmembrane segment, and a cytoplasmic tail with three conserved signaling motifs: CC0, CC2, and CC3 (CC for conserved cytoplasmic). Unlike other ROBO family members, ROBO3 lacks motif CC1. The ROBO3 gene regulates axonal navigation at the ventral midline of the neural tube. In mouse, loss of Robo3 results in a complete failure of commissural axons to cross the midline throughout the spinal cord and the hindbrain. Mutations ROBO3 result in horizontal gaze palsy with progressive scoliosis (HGPPS); an autosomal recessive disorder characterized by congenital absence of horizontal gaze, progressive scoliosis, and failure of the corticospinal and somatosensory axon tracts to cross the midline in the medulla. Alternative transcript variants have been described but have not been experimentally validated. [provided by RefSeq, Dec 2009]

Full Name

roundabout, axon guidance receptor, homolog 3 (Drosophila)

Function

Thought to be involved during neural development in axonal navigation at the ventral midline of the neural tube (By similarity).
In spinal cord development plays a role in guiding commissural axons probably by preventing premature sensitivity to Slit proteins thus inhibiting Slit signaling through ROBO1 (By similarity).
Required for hindbrain axon midline crossing (PubMed:15105459).

Biological Process

Biological Process axon guidanceISS:UniProtKB
Biological Process axon midline choice point recognitionISS:UniProtKB
Biological Process dendrite self-avoidanceManual Assertion Based On ExperimentIBA:GO_Central
Biological Process homophilic cell adhesion via plasma membrane adhesion moleculesManual Assertion Based On ExperimentIBA:GO_Central

Cellular Location

Membrane

Involvement in disease

Gaze palsy, familial horizontal, with progressive scoliosis, 1 (HGPPS1):
An autosomal recessive neurologic disorder characterized by eye movement abnormalities apparent from birth, childhood-onset progressive scoliosis, distinctive brainstem malformation and defective crossing of some brainstem neuronal pathways.

Topology

Extracellular: 21-891
Helical: 892-912
Cytoplasmic: 913-1386