Kunitz-type domain from the alpha1 chain of type VII collagen, and similar proteins
This model includes the Kunitz-type domain from the alpha1 chain of type VII collagen (collagen alpha-1(VII) chain also called long-chain collagen or LC collagen) and similar proteins. LC collagen, encoded by the COL7A1 gene, is a stratified squamous epithelial basement membrane protein that forms anchoring fibrils which may contribute to epithelial basement membrane organization and adherence by interacting with extracellular matrix (ECM) proteins such as type IV collagen. So far, over 800 COL7A1 mutations have been reported, including missense, nonsense, splicing, insertion, and deletion mutations which to varying degrees leads to deficiency of type VII collagen. Epidermolysis bullosa acquisita (EBA) is an autoimmune acquired blistering skin disease resulting from autoantibodies to type VII collagen. The COL7A1 protein contains a Kunitz domain, the deactivation of which induces tumorigenesis. This domain is similar to that of Kunitz-type proteinase inhibitors such as BPTI (bovine pancreatic trypsin inhibitor), that shows an alpha/beta fold with irregular secondary structure stabilized by three disulfide bonds.
Jiyao W et al.(2023). "The conserved domain database in 2023.",