SERPINA3
Serpin Family A Member 3 (Alpha-1-Antichymotrypsin)
Gene Information Card
| Symbol | SERPINA3 |
|---|---|
| Full Name | Serpin Family A Member 3 |
| Gene Type | protein-coding |
| Chromosomal Location | 14q32.13 |
| NCBI Gene ID | 12 ncbi.nlm.nih.gov/gene/12 |
| Ensembl ID | ENSG00000196136 |
| UniProt ID | P01011 |
| OMIM ID | 107280 |
| HGNC ID | 16 |
| Aliases | AACT, ACT, GIG24, GIG25, MGC88254, alpha-1-antichymotrypsin |
Description
SERPINA3 (Serpin Family A Member 3) encodes alpha-1-antichymotrypsin, a member of the serpin superfamily of serine protease inhibitors. It inhibits cathepsin G and chymotrypsin, and is involved in acute-phase inflammatory responses. The protein is primarily secreted by the liver and is found in plasma. Mutations and altered expression of SERPINA3 are associated with Alzheimer disease, chronic obstructive pulmonary disease (COPD), and various cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Alzheimer disease | SERPINA3 is a component of amyloid plaques; it binds to amyloid-beta and may promote fibril formation. Increased expression in brain is associated with neuroinflammation. | ClinVar, OMIM |
| Chronic obstructive pulmonary disease | Alpha-1-antichymotrypsin deficiency leads to unopposed protease activity in lung tissue, contributing to emphysema. | ClinVar, OMIM |
| Liver disease | Deficiency of alpha-1-antichymotrypsin can cause liver dysfunction due to protein accumulation. | ClinVar |
| Cancer (various) | Overexpression in breast, prostate, and lung cancers; may promote tumor invasion and metastasis by modulating protease activity. | COSMIC, NCBI |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Liver | 1000.0 | High |
| Lung | 50.0 | Medium |
| Brain | 30.0 | Medium |
| Kidney | 20.0 | Low |
| Heart | 15.0 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HepG2 | 1200.0 | Hepatocellular carcinoma cell line |
| A549 | 60.0 | Lung adenocarcinoma cell line |
| SH-SY5Y | 40.0 | Neuroblastoma cell line |
| MCF7 | 25.0 | Breast cancer cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| p.Pro227Ala | Missense | <0.1% | Reduced inhibitory activity; associated with COPD |
| p.Leu55Pro | Missense | <0.1% | Impaired secretion; associated with liver disease |
| p.Arg125Cys | Missense | <0.1% | Altered protein stability; reported in Alzheimer disease |
Mutation functional classification
Loss of Function (LOF)
Mutations such as p.Pro227Ala reduce protease inhibitory activity, leading to unopposed protease activity in tissues.
Gain of Function (GOF)
Not well documented; some variants may increase aggregation propensity.
Dominant Negative (DN)
Not reported for SERPINA3.
View complete mutation data：
Gene Ontology (GO)
| • serine-type endopeptidase inhibitor activity | • protease binding |
| • extracellular space | • blood microparticle |
| • acute-phase response | • negative regulation of endopeptidase activity |
Pathways
• Innate Immune System
• Complement and Coagulation Cascades
• Alzheimer disease-amyloid plaque formation
Protein Summary
Alpha-1-antichymotrypsin is a 423-amino-acid glycoprotein (mature form) with a molecular weight of approximately 55 kDa. It belongs to the serpin family and inhibits serine proteases such as cathepsin G. The protein is synthesized primarily in the liver and secreted into plasma. It plays a role in inflammation, tissue repair, and modulation of immune responses. In the brain, it is produced by astrocytes and is a component of senile plaques in Alzheimer disease.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SERPINA3 Knockout HEK293 Cell Line | EDJ-KQ3103 | Human | 12 | Details Get a Quote |
| SERPINA3 Knockout A-549 Cell Line | EDJ-KQ24434 | Human | 12 | Details Get a Quote |
| SERPINA3 Knockout HeLa Cell Line | EDJ-KQ52529 | Human | 12 | Details Get a Quote |
| SERPINA3 Knockout HCT 116 Cell Line | EDJ-KQ69485 | Human | 12 | Details Get a Quote |
