The protein encoded by this gene is a plasma protease inhibitor and member of the serine protease inhibitor class. Polymorphisms in this protein appear to be tissue specific and influence protease targeting. Variations in this proteins sequence have been implicated in Alzheimers disease, and deficiency of this protein has been associated with liver disease. Mutations have been identified in patients with Parkinson disease and chronic obstructive pulmonary disease. [provided by RefSeq, Jul 2008],caution:It is uncertain whether Met-1 or Met-4 is the initiator.,disease:Defects in SERPINA3 may be a cause of chronic obstructive pulmonary disease (COPD) [MIM:107280].,domain:The reactive center loop (RCL) extends out from the body of the protein and directs binding to the target protease. The protease cleaves the serpin at the reactive site within the RCL, establishing a covalent linkage between the carboxyl group of the serpin reactive site and the serine hydroxyl of the protease. The resulting inactive serpin-protease complex is highly stable.,function:Although its physiological function is unclear, it can inhibit neutrophil cathepsin G and mast cell chymase, both of which can convert angiotensin-1 to the active angiotensin-2.,miscellaneous:Alpha-1-antichymotrypsin can bind DNA.,online information:Alpha-1 antichymotrypsin entry,sequence caution:Translation N-terminally shortened.,similarity:Belongs to the serpin family.,subunit:Interacts with DNAJC1.,tissue specificity:Plasma. Synthesized in the liver. Like the related alpha-1-antitrypsin, its concentration increases in the acute phase of inflammation or infection. Found in the myloid plaques from the hippocampus of Alzheimers disease brains.,
