Alpha 1-antichymotrypsin

Alpha 1-antichymotrypsin (symbol α₁AC,[4] 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
Gene location (Human) Chr. Chromosome 14 (human)[1] Band 14q32.13 Start 94,612,384 bp[1] End 94,624,055 bp[1]
RNA expression pattern More reference expression data
Gene ontology Molecular function • peptidase inhibitor activity • DNA binding • GO:0001948 protein binding • serine-type endopeptidase inhibitor activity Cellular component • blood microparticle • extracellular exosome • intracellular • cell nucleus • platelet alpha granule lumen • extracellular region • extracellular • 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	n/a
UniProt	P01011	P07759
RefSeq (mRNA)	NM_001085	NM_011458
RefSeq (protein)	NP_001076	NP_035588
Location (UCSC)	Chr 14: 94.61 – 94.62 Mb	n/a
PubMed search	[2]	[3]
Wikidata
View/Edit Human View/Edit Mouse

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.[5]

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.[6]

Alpha 1-antichymotrypsin is also associated with the pathogenesis of Alzheimer's disease as it enhances the formation of amyloid-fibrils in this disease.[5]

Interactions

Alpha 1-antichymotrypsin has been shown to interact with DNAJC1.[7]

See also

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

References

1. GRCh38: Ensembl release 89: ENSG00000196136 - Ensembl, May 2017
2. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
3. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
4. Logan, Carolynn M.; Rice, M. Katherine (1987). Logan's Medical and Scientific Abbreviations. Philadelphia: J. B. Lippincott Company. p. 3. ISBN 0-397-54589-4.
5. Kalsheker N (1996). "Alpha 1-antichymotrypsin". Int. J. Biochem. Cell Biol. 28 (9): 961–4. doi:10.1016/1357-2725(96)00032-5. PMID 8930118.
6. "Entrez Gene: SERPINA3 serpin peptidase inhibitor, clade A (alpha-1 antiproteinase, antitrypsin), member 3".
7. Kroczynska B, Evangelista CM, Samant SS, Elguindi EC, Blond SY (March 2004). "The SANT2 domain of the murine tumor cell DnaJ-like protein 1 human homologue interacts with alpha1-antichymotrypsin and kinetically interferes with its serpin inhibitory activity". J. Biol. Chem. 279 (12): 11432–43. doi:10.1074/jbc.M310903200. PMC 1553221. PMID 14668352.

Further reading

• Janciauskiene S, Wright HT (1999). "Inflammation, antichymotrypsin, and lipid metabolism: autogenic etiology of Alzheimer's disease". BioEssays. 20 (12): 1039–46. doi:10.1002/(SICI)1521-1878(199812)20:12<1039::AID-BIES10>3.0.CO;2-Z. PMID 10048303.
• Kalsheker N, Morley S, Morgan K (2002). "Gene regulation of the serine proteinase inhibitors alpha1-antitrypsin and alpha1-antichymotrypsin". Biochem. Soc. Trans. 30 (2): 93–8. doi:10.1042/BST0300093. PMID 12023832.

External links

• The MEROPS online database for peptidases and their inhibitors: I04.002
• Alpha+1-antichymotrypsin at the US National Library of Medicine Medical Subject Headings (MeSH)
• Human SERPINA3 genome location and SERPINA3 gene details page in the UCSC Genome Browser.
• Overview of all the structural information available in the PDB for UniProt: P01011 (Human Alpha-1-antichymotrypsin) at the PDBe-KB.