CYBA: Cytochrome b-245 Alpha Chain
A critical component of the phagocyte NADPH oxidase complex involved in immune defense and linked to chronic granulomatous disease.
Gene Information Card
| Symbol | CYBA |
|---|---|
| Full Name | Cytochrome b-245 alpha chain |
| Gene Type | protein-coding |
| Chromosomal Location | 16q24.3 |
| NCBI Gene ID | 1535 ncbi.nlm.nih.gov/gene/1535 |
| Ensembl ID | ENSG00000051523 |
| UniProt ID | P13498 |
| OMIM ID | 233690 |
| HGNC ID | 2577 |
| Aliases | p22phox, CGD, CYBA_HUMAN |
Description
The CYBA gene encodes the alpha subunit (p22phox) of cytochrome b245, a critical component of the phagocyte NADPH oxidase system. This enzyme complex generates superoxide anions for microbial killing in phagocytes. Mutations in CYBA cause autosomal recessive chronic granulomatous disease (CGD), characterized by recurrent infections and granuloma formation.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Chronic granulomatous disease (CGD) | Loss-of-function mutations in CYBA impair NADPH oxidase activity, preventing superoxide production and leading to defective microbial killing. | ClinVar, OMIM |
| Atherosclerosis | Reduced NADPH oxidase activity may alter vascular oxidative stress, though direct evidence is limited. | NCBI Gene, PubMed |
| Hypertension | Polymorphisms in CYBA have been associated with altered oxidative stress and blood pressure regulation. | NCBI Gene, PubMed |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Bone marrow | 12.5 | Medium |
| Spleen | 8.3 | Medium |
| Lung | 6.1 | Low |
| Blood | 5.4 | Low |
| Liver | 2.0 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| THP-1 (monocyte) | 15.2 | High expression in myeloid cells |
| HL-60 (promyeloblast) | 12.8 | Differentiation increases expression |
| K-562 (erythroleukemia) | 1.5 | Low expression |
| HeLa (cervical carcinoma) | 0.8 | Very low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.287A>G (p.Asp96Gly) | Missense | Rare | Loss of function; associated with CGD |
| c.352C>T (p.Arg118Trp) | Missense | Rare | Loss of function; associated with CGD |
| c.1A>G (p.Met1Val) | Missense | Rare | Loss of function; associated with CGD |
| c.168C>A (p.Tyr56Ter) | Nonsense | Rare | Loss of function; associated with CGD |
Mutation functional classification
Loss of Function (LOF)
Most CYBA mutations cause loss of function, leading to chronic granulomatous disease due to defective NADPH oxidase activity.
Gain of Function (GOF)
No gain-of-function mutations reported.
Dominant Negative (DN)
No dominant-negative mutations reported; CYBA mutations are typically recessive.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Phagosome (KEGG: hsa04145)
• NADPH oxidase complex (Reactome: R-HSA-5668599)
• Innate Immune System (Reactome: R-HSA-168249)
Protein Summary
The CYBA protein (p22phox) is a 22 kDa transmembrane subunit of cytochrome b245, the catalytic core of the phagocyte NADPH oxidase. It stabilizes and anchors the catalytic subunit NOX2 (gp91phox) to the membrane. p22phox contains heme-binding sites essential for electron transfer. Defects in this protein disrupt superoxide production, leading to chronic granulomatous disease.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CYBA Knockout HEK293 Cell Line | EDJ-KQ2966 | Human | 1535 | Details Get a Quote |
| CYBA Knockout HCT 116 Cell Line | EDJ-KQ24120 | Human | 1535 | Details Get a Quote |
| CYBA Knockout HeLa Cell Line | EDJ-KQ24121 | Human | 1535 | Details Get a Quote |
| CYBA Knockout A-549 Cell Line | EDJ-KQ22748 | Human | 1535 | Details Get a Quote |
