LPO Gene - Lactoperoxidase
Comprehensive genomic and functional analysis of the LPO gene encoding lactoperoxidase, a key antimicrobial enzyme.
Gene Information Card
| Symbol | LPO |
|---|---|
| Full Name | lactoperoxidase |
| Gene Type | protein coding |
| Chromosomal Location | 17q23.1 |
| NCBI Gene ID | 4025 ncbi.nlm.nih.gov/gene/4025 |
| Ensembl ID | ENSG00000167419 |
| UniProt ID | P22079 |
| OMIM ID | 150205 |
| HGNC ID | 6678 |
| Aliases | SPO, LPOX |
Description
The LPO gene encodes lactoperoxidase, a heme-containing peroxidase enzyme primarily secreted in milk, saliva, tears, and other mucosal secretions. It catalyzes the oxidation of thiocyanate (SCN-) to hypothiocyanite (OSCN-), generating antimicrobial activity against bacteria, fungi, and viruses. LPO plays a critical role in innate immunity and host defense.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Periodontitis | Reduced LPO activity may impair oral antimicrobial defense, contributing to periodontal inflammation. | Case-control studies show lower LPO levels in saliva of periodontitis patients (PMID: 23866106). |
| Cystic Fibrosis | Altered LPO expression in airway secretions may affect bacterial colonization. | Observational studies report decreased LPO activity in CF sputum (PMID: 21908264). |
| Breast Cancer | LPO expression is reduced in breast tumor tissues, potentially affecting local immunity. | Immunohistochemistry studies show lower LPO in malignant vs. normal breast tissue (PMID: 19782035). |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Mammary gland | 123.4 | High |
| Salivary gland | 89.2 | High |
| Lung | 12.1 | Low |
| Trachea | 8.5 | Low |
| Kidney | 2.3 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| MCF7 (breast cancer) | 45.6 | Moderate expression |
| A549 (lung cancer) | 3.2 | Low expression |
| HepG2 (liver cancer) | 1.1 | Not detected |
| HeLa (cervical cancer) | 0.8 | Not detected |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.203C>T (p.Ala68Val) | missense | 0.01% | Unknown functional effect |
| c.1129G>A (p.Gly377Ser) | missense | 0.005% | Reported in ClinVar as uncertain significance |
| c.1654C>T (p.Arg552Trp) | missense | 0.002% | No functional data |
Mutation functional classification
Loss of Function (LOF)
No confirmed loss-of-function mutations reported in ClinVar or COSMIC.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported.
View complete mutation data：
Gene Ontology (GO)
| • peroxidase activity (GO:0004601) | • heme binding (GO:0020037) |
| • hydrogen peroxide catabolic process (GO:0042744) | • oxidation-reduction process (GO:0055114) |
| • extracellular region (GO:0005576) |
Pathways
• Reactome: Antimicrobial peptides (R-HSA-6803157)
• KEGG: Peroxidase pathway (ko04146)
Protein Summary
Lactoperoxidase (UniProt P22079) is a 712-amino acid glycoprotein with a molecular weight of approximately 80 kDa. It contains a heme prosthetic group and belongs to the peroxidase family. The enzyme is secreted as a monomer and uses hydrogen peroxide to oxidize thiocyanate, generating hypothiocyanite, a potent antimicrobial agent. It is highly expressed in exocrine secretions and contributes to mucosal immunity.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| LPO Knockout HEK293 Cell Line | EDJ-KQ2795 | Human | 4025 | Details Get a Quote |
| LPO Knockout HeLa Cell Line | EDJ-KQ53803 | Human | 4025 | Details Get a Quote |
| LPO Knockout A-549 Cell Line | EDJ-KQ62284 | Human | 4025 | Details Get a Quote |
| LPO Knockout HCT 116 Cell Line | EDJ-KQ70765 | Human | 4025 | Details Get a Quote |
