SEMA3C (also designated Semaphorin 3C, Semaphorin E, SEMAE, SemE,sema domain, immunoglobulin domain (Ig) and short basic domain, secreted)is an ubiquitous protein of approximately 70 kDa that mediates axonal guidance, repulsive gradients, induction of growth cone collapse and cell survival/death. Secreted SEMA3C favors survival and neuritogenesis of cultured cerebellar granule neurons (CGNs). SEMA3C from macrophages and fibroblasts that selectively directs against sympathetic nerve fibers may be one element responsible for reduced sympathetic innervation in rheumatoid arthritis tissue.SEMA3C mutant mice die within hours after birth from congenital cardiovascular defects consisting of interruption of the aortic arch and improper septation of the cardiac outflow tract. SEMA3C is expressed in the cardiac outflow ract as neural crest cells and promotes crest cell migration into the proximal cardiac outflow tract.