Alpha 1-antichymotrypsin

Alpha 1-antichymotrypsin (symbol α₁AC,^[5] A1AC, or a1ACT) is an alpha globulin glycoprotein that is a member of the serpin superfamily. In humans, it is encoded by the SERPINA3 gene.

SERPINA3
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1AS4, 1QMN, 2ACH, 3CAA, 3DLW, 4CAA
Identifiers
Aliases	SERPINA3, AACT, ACT, GIG24, GIG25, serpin family A member 3
External IDs	OMIM: 107280; MGI: 98377; HomoloGene: 111129; GeneCards: SERPINA3; OMA:SERPINA3 - orthologs
Gene location (Human) Chr. Chromosome 14 (human)[1] Band 14q32.13 Start 94,612,384 bp[1] End 94,624,055 bp[1]
Gene location (Mouse) Chr. Chromosome 12 (mouse)[2] Band 12 E|12 53.99 cM Start 104,304,745 bp[2] End 104,312,403 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in right lobe of liver body of pancreas islet of Langerhans gastric mucosa left coronary artery right coronary artery gallbladder left uterine tube right lung right ovary Top expressed in left lobe of liver sexually immature organism pharynx parotid gland spinal ganglia basal plate medial head of gastrocnemius muscle adrenal gland white adipose tissue duodenum More reference expression data BioGPS More reference expression data
Gene ontology Molecular function peptidase inhibitor activity DNA binding protein binding serine-type endopeptidase inhibitor activity Cellular component blood microparticle extracellular exosome intracellular anatomical structure nucleus platelet alpha granule lumen extracellular region extracellular space secretory granule lumen azurophil granule lumen collagen-containing extracellular matrix Biological process regulation of lipid metabolic process negative regulation of peptidase activity inflammatory response maintenance of gastrointestinal epithelium acute-phase response platelet degranulation negative regulation of endopeptidase activity neutrophil degranulation Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 12 20714 Ensembl ENSG00000196136 ENSMUSG00000058207 UniProt P01011 P07759 RefSeq (mRNA) NM_001085 NM_011458 RefSeq (protein) NP_001076 NP_035588 Location (UCSC) Chr 14: 94.61 – 94.62 Mb Chr 12: 104.3 – 104.31 Mb PubMed search [3] [4]
Wikidata
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Function

Alpha 1-antichymotrypsin inhibits the activity of certain enzymes called proteases, such as cathepsin G that is found in neutrophils, and chymases found in mast cells, by cleaving them into a different shape or conformation. This activity protects some tissues, such as the lower respiratory tract, from damage caused by proteolytic enzymes.^[6]

This protein is produced in the liver, and is an acute phase protein that is induced during inflammation.

Clinical significance

Deficiency of this protein has been associated with liver disease. Mutations have been identified in patients with Parkinson disease and chronic obstructive pulmonary disease.^[7]

Alpha 1-antichymotrypsin is also associated with the pathogenesis of Alzheimer's disease as it enhances the formation of amyloid-fibrils in this disease.^[6]

Interactions

Alpha 1-antichymotrypsin has been shown to interact with DNAJC1.^[8]

See also

• Alpha-1 antitrypsin, another serpin that is analogous for protecting the body from excessive effects of its own inflammatory proteases