serpin family E member 2, glia derived nexin (GDN)
Serpin glia-derived nexin (GDN; also called peptidase inhibitor 7/PI-7 or protease nexin 1/PN-1) is a specific and extremely efficient inhibitor of thrombin. Unlike other thrombin inhibitors, it is not synthesized in the liver and does not circulate in the blood. It is instead expressed by multiple cell types and is located on the surface of these cells, bound to glycosaminoglycans. GDN plays a role in thrombosis and atherosclerosis and is a clade E serpin. In general, SERine Proteinase INhibitors (serpins) exhibit conformational polymorphism shifting from native to cleaved, latent, delta, or polymorphic forms. Many serpins, such as antitrypsin and antichymotrypsin, function as serine protease inhibitors which regulate blood coagulation cascades. Non-inhibitory serpins perform many diverse functions such as chaperoning proteins or transporting hormones. Serpins are of medical interest because mutants have been associated with blood clotting disorders, emphysema, cirrhosis, and dementia. A classification based on evolutionary relatedness has resulted in the assignment of serpins to 16 clades designated A-P along with some orphans.
Comment:depending on the conformational state, the RC loop is surface accessible in the active form or buried and inserted as the central beta strand in the inactive form.
Structure:4DY7_C: Human glia-derived nexin RCL, solvent-exposed
Jiyao W et al.(2023). "The conserved domain database in 2023.",