insect serpins similar to Anopheles gambiae Serpin 18
Serpins in insects function within development, wound healing and immunity. A. gambiae serpin 18 is categorized as non-inhibitory based on the sequence of its reactive-center loop. It is expressed throughout all life stages in multiple tissues and the hemolymph, and is predicted to be secreted based on the presence of a signal peptide. Insect serpins from mosquitoes are included in this subfamily. 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.
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