Type XVI collagen

Type XVI collagen is part of the family of fibril-associated collagens with interrupted triple helices that do not form fibrils themselves but rather associate with fibril-forming collagens as single molecules. Type XVI collagen is synthesized by various cell types, including fibroblasts, dendrocytes, keratinocytes, smooth muscle cells, chondrocytes, and myofibroblasts. It is expressed in several tissues, such as skin, cartilage, heart, intestine, lung, arterial walls, and kidney. Type XVI collagen binds to integrins, type II and XI collagen, fibrillin-1, and fibronectin. Its main functions are to organize the extracellular matrix by stabilizing collagen fibrils and focal adhesions and anchoring microfibrils to the basement membrane, along with mediating intracellular signaling that affects cell adhesion, proliferation, invasiveness, and the formation of focal adhesions. One biomarker of type XVI collagen has been described and been shown to be elevated in patients with gastrointestinal disorders.