Serpin Inhibition Mechanism: A Delicate Balance between Native Metastable State and Polymerization

Figure 2

Important domains in serpin conformations. Several regions are important in controlling and modulating serpin conformational changes. The Reactive Centre Loop is involved in protease recognition and conformational transformation as strand 4A after inhibition. The P15–P9 portion of the RCL is called the hinge region. The point of initial insertion of the RCL which is the breach region, located at the top of the A β-sheet. Near the center of A β-sheet is the shutter domain. The breach and shutter are two major regions that assist sheet opening and accept the conserved hinge of the RCL when it inserts. The gate region is composed of s3C and s4C strands which has been primarily observed by studies of the transition latency. The image was drawn in chimera using the PDB file of native antitrypsin conformation.