APEX2: Apurinic/Apyrimidinic Endodeoxyribonuclease 2
A key enzyme in DNA base excision repair and redox regulation
Gene Information Card
| Symbol | APEX2 |
|---|---|
| Full Name | Apurinic/Apyrimidinic Endodeoxyribonuclease 2 |
| Gene Type | Protein coding |
| Chromosomal Location | Xp11.21 |
| NCBI Gene ID | 27301 ncbi.nlm.nih.gov/gene/27301 |
| Ensembl ID | ENSG00000169188 |
| UniProt ID | Q9UBZ4 |
| OMIM ID | 300773 |
| HGNC ID | 597 |
| Aliases | APE2, APEXL, XTH2 |
Description
APEX2 encodes a member of the AP endonuclease family, which is involved in the base excision repair (BER) pathway. The protein has both apurinic/apyrimidinic (AP) endonuclease and 3'-5' exonuclease activities, and also functions as a redox regulator. It is essential for repairing oxidative DNA damage and maintaining genomic stability.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Breast cancer | Altered expression and mutations in APEX2 may impair DNA repair, contributing to genomic instability and tumorigenesis. | COSMIC; PMID: 25612906 |
| Lung cancer | Somatic mutations and overexpression of APEX2 have been reported, potentially affecting BER efficiency and response to oxidative stress. | COSMIC; PMID: 28492532 |
| Colorectal cancer | APEX2 mutations and altered expression levels are associated with microsatellite instability and poor prognosis. | COSMIC; PMID: 27197191 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 12.5 | Medium |
| Bone marrow | 8.2 | Low |
| Lymph node | 6.1 | Low |
| Spleen | 5.4 | Low |
| Brain | 2.3 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 10.1 | Cervical cancer cell line |
| A549 | 9.8 | Lung cancer cell line |
| MCF7 | 8.5 | Breast cancer cell line |
| HEK293 | 7.2 | Embryonic kidney cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| p.Arg274Trp | Missense | <0.01% | Unknown functional impact; reported in COSMIC |
| p.Gly241Asp | Missense | <0.01% | Potential loss of endonuclease activity |
| p.Thr304Met | Missense | <0.01% | Reported in ClinVar as variant of uncertain significance |
Mutation functional classification
Loss of Function (LOF)
Mutations in the catalytic domain (e.g., p.Gly241Asp) may reduce AP endonuclease activity, impairing BER.
Gain of Function (GOF)
No confirmed gain-of-function mutations reported.
Dominant Negative (DN)
No evidence for dominant-negative effects.
View complete mutation data：
Gene Ontology (GO)
| • DNA repair | • base-excision repair |
| • apurinic/apyrimidinic endonuclease activity | • 3'-5' exonuclease activity |
| • redox regulation | • nucleus |
| • mitochondrion |
Pathways
• Base excision repair (BER)
• DNA damage response
Protein Summary
APEX2 is a 518-amino acid protein with a conserved endonuclease domain. It localizes to both the nucleus and mitochondria, where it processes AP sites and 3' blocking lesions during BER. It also exhibits redox activity, regulating transcription factors such as p53 and NF-κB. The protein is essential for cellular response to oxidative stress.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| APEX2 Knockout HEK293 Cell Line | EDJ-KQ8754 | Human | 27301 | Details Get a Quote |
| APEX2 Knockout A-549 Cell Line | EDJ-KQ35001 | Human | 27301 | Details Get a Quote |
| APEX2 Knockout HCT 116 Cell Line | EDJ-KQ35002 | Human | 27301 | Details Get a Quote |
| APEX2 Knockout HeLa Cell Line | EDJ-KQ35003 | Human | 27301 | Details Get a Quote |
