COL5A2 is a component of type V collagen. It is known as the pro-alpha2(V) chain. COL5A2, together with two pro-alpha1(V) chains can form type V procollagen. These triple-stranded, rope-like procollagen molecules arrange themselves into long, thin fibrils that cross-link to one another in the spaces around cells. The cross-links result in the formation of very strong, mature type V collagen fibers. Type V collagen can be detected in tissues containing type I collagen and appears to regulate the assembly of heterotypic fibers composed of both type I and type V collagen.