Latrophilin-2 is an Orphan-B Receptor that binds alpha-latrotoxin, a potent presynaptic neurotoxin present in the venom of the black widow spider, in a Ca2+-independent manner. As with the other two latrophilins, it shares homology with lectin, olfactomedin, and transmembrane domains, and possesses variable C-termini and various alternative-splice sites. Latrophilin-2 is endoproteolytically cleaved at the end of the GPS domain, and the two subunits remain non-covantely linked as a heterodimer. Latrophilin-2 expressed is widespread and has been documented in brain, breast, placenta, kidney, spleen, ovary, heart, and lung. ESTs have been isolated from a wide variety of tissue libraries.