ROBO2 Recombinant Rabbit mAb (S-4563-43)

ROBO2 (Roundabout homolog 2) is a single-pass type I transmembrane protein encoded by the ROBO2 gene located on human chromosome 3, containing approximately 1,420 amino acids with a molecular weight of about 155.8 kDa. As an important member of the Roundabout family of axon guidance receptors, ROBO2 has a typical extracellular domain organization comprising five immunoglobulin-like domains (D1-D5) and three fibronectin type III domains (D6-D8), followed by a single transmembrane region and a largely unstructured intracellular segment. The function of ROBO2 is tightly controlled by an autoinhibitory mechanism: its extracellular D4 domain mediates cis-dimerization, but in the inactive state the dimerization interface of D4 is blocked intramolecularly in cis, while trans interactions further reinforce this blocked conformation. When the secreted ligand Slit binds ROBO2, this autoinhibition is relieved, D4-mediated dimerization occurs, and this in turn triggers conformational changes in the intracellular segment and recruits downstream effector molecules (such as SRGAP, Abl, and SOS) to transduce signals. Functionally, ROBO2 primarily acts as a repulsive receptor for axon guidance, responsible for the guidance of dorsal funiculus axons and for preventing neuronal cell bodies from migrating away from the floor plate region. In addition, ROBO2 participates in regulating the proliferation and differentiation of neural progenitor cells through crosstalk with the Notch pathway, and plays roles in the development of organs such as the lung, kidney, and heart.