TSPAN12: ProductsTSPAN12 is a member of the transmembrane 4 superfamily, also known as the tetraspanin family. They mediate signal transduction events that play a role in the regulation of cell development, activation, growth and motility. TSPAN12 plays a central role in retinal vascularization by regulating norrin signal transduction. TSPAN12 acts in concert with norrin to promote FZD4 multimerization and subsequent activation of FZD4, leading to promote accumulation of beta-catenin and stimulate LEF/TCF-mediated transcriptional programs. Defects in TSPAN12 are the cause of vitreoretinopathy exudative type 5, a disorder of the retinal vasculature characterized by an abrupt cessation of growth of peripheral capillaries, leading to an avascular peripheral retina.