This gene encodes a member of the type II transmembrane serine protease family. The encoded protein contains a type II transmembrane domain, a receptor class A domain, a scavenger receptor cysteine-rich domain and a protease domain. Transmembrane serine proteases are regulated by protease inhibitors and known to function in development, homeostasis, infection, and tumorigenesis. This protein facilitates entry of viruses into host cells by proteolytically cleaving and activating viral envelope glycoproteins.