AOC1: Amine Oxidase, Copper Containing 1
Key enzyme in histamine and polyamine metabolism, implicated in inflammatory and neoplastic disorders.
Gene Information Card
| Symbol | AOC1 |
|---|---|
| Full Name | Amine oxidase, copper containing 1 |
| Gene Type | protein-coding |
| Chromosomal Location | 7q36.1 |
| NCBI Gene ID | 26 ncbi.nlm.nih.gov/gene/26 |
| Ensembl ID | ENSG00000106356 |
| UniProt ID | P19801 |
| OMIM ID | 104610 |
| HGNC ID | 548 |
| Aliases | DAO, KAO, ABP1, amiloride-binding protein 1, histaminase, diamine oxidase |
Description
AOC1 encodes a copper-containing amine oxidase that catalyzes the oxidative deamination of biogenic amines such as histamine, putrescine, and cadaverine. The enzyme is a homodimer with a tightly bound copper ion and a topaquinone cofactor. It is primarily expressed in the kidney, placenta, and gastrointestinal tract, and plays a critical role in histamine catabolism and polyamine homeostasis. Dysregulation of AOC1 has been linked to inflammatory bowel disease, allergic disorders, and certain cancers.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Histamine intolerance | Reduced AOC1 activity leads to accumulation of dietary histamine, causing headache, flushing, and gastrointestinal symptoms. | ClinVar; OMIM #104610 |
| Inflammatory bowel disease (IBD) | Altered AOC1 expression in intestinal mucosa may impair histamine degradation, contributing to chronic inflammation. | NCBI Gene; PubMed studies |
| Colorectal cancer | AOC1 expression is downregulated in tumor tissues; loss of enzyme activity may promote polyamine-driven tumor growth. | COSMIC; PubMed studies |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Kidney | 45.2 | High |
| Small intestine | 38.7 | High |
| Placenta | 32.1 | High |
| Colon | 18.5 | Medium |
| Liver | 5.3 | Low |
| Lung | 2.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK 293 | 12.4 | Embryonic kidney cells; moderate expression |
| Caco-2 | 28.9 | Colorectal adenocarcinoma; high expression |
| HepG2 | 3.2 | Hepatocellular carcinoma; low expression |
| A549 | 1.8 | Lung carcinoma; very low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1046G>A (p.Arg349Gln) | Missense | Rare | Reduced enzyme activity; associated with histamine intolerance |
| c.1250T>C (p.Leu417Pro) | Missense | Rare | Decreased catalytic efficiency; reported in IBD patients |
| c.1601_1602delAG | Frameshift | Very rare | Loss of function; likely pathogenic |
Mutation functional classification
Loss of Function (LOF)
Missense and frameshift mutations that reduce or abolish diamine oxidase activity, leading to histamine accumulation.
Gain of Function (GOF)
No gain-of-function mutations have been reported for AOC1.
Dominant Negative (DN)
No dominant-negative effects have been described for AOC1.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Histamine degradation (Reactome: R-HSA-2162123)
• Amine compound metabolism (KEGG: map00330)
• Arginine and proline metabolism (KEGG: map00330)
Protein Summary
AOC1 encodes diamine oxidase (DAO), a homodimeric copper-containing enzyme that oxidizes histamine and other diamines. The protein is anchored to the plasma membrane via a signal peptide and is also secreted. It contains a conserved copper-binding domain and a topaquinone cofactor essential for catalysis. DAO is the primary enzyme responsible for the degradation of extracellular histamine, thereby regulating allergic and inflammatory responses.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| AOC1 Knockout HEK293 Cell Line | EDJ-KQ3988 | Human | 26 | Details Get a Quote |
| AOC1 Knockout HeLa Cell Line | EDJ-KQ26302 | Human | 26 | Details Get a Quote |
| AOC1 Knockout A-549 Cell Line | EDJ-KQ61015 | Human | 26 | Details Get a Quote |
| AOC1 Knockout HCT 116 Cell Line | EDJ-KQ69489 | Human | 26 | Details Get a Quote |
Displaying Records 1 To 4 Of 4 Records
