GJB5 (Gap Junction Protein Beta 5)
Connexin 31.1: A key component of gap junctions in skin and cochlea
Gene Information Card
| Symbol | GJB5 |
|---|---|
| Full Name | Gap Junction Protein Beta 5 |
| Gene Type | Protein coding |
| Chromosomal Location | 1p34.3 |
| NCBI Gene ID | 2717 ncbi.nlm.nih.gov/gene/2717 |
| Ensembl ID | ENSG00000189280 |
| UniProt ID | O95377 |
| OMIM ID | 600313 |
| HGNC ID | 4287 |
| Aliases | CX31.1, connexin 31.1 |
Description
GJB5 (Gap Junction Protein Beta 5) encodes connexin 31.1, a member of the connexin protein family that forms gap junction channels facilitating intercellular communication. It is primarily expressed in the epidermis and inner ear, playing a critical role in skin barrier function and cochlear homeostasis. Mutations in GJB5 are associated with erythrokeratoderma variabilis et progressiva (EKVP) and nonsyndromic hearing loss.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Erythrokeratoderma variabilis et progressiva (EKVP) | Missense mutations in GJB5 disrupt gap junction assembly in keratinocytes, leading to abnormal epidermal differentiation and hyperkeratosis. | ClinVar, OMIM |
| Nonsyndromic hearing loss (DFNA) | Loss-of-function variants impair gap junction coupling in cochlear supporting cells, affecting potassium recycling and auditory transduction. | ClinVar, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Skin | 12.5 | Medium |
| Esophagus | 8.3 | Low |
| Cochlea | 6.1 | Low |
| Tongue | 4.7 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HaCaT (keratinocyte) | 15.2 | High expression in skin-derived cell line |
| HEK293 | 2.1 | Low endogenous expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.35G>A (p.Gly12Asp) | Missense | <0.01% | Dominant-negative effect; associated with EKVP |
| c.101T>C (p.Leu34Pro) | Missense | <0.01% | Impaired trafficking; hearing loss |
| c.560G>A (p.Arg187Gln) | Missense | <0.01% | Reduced channel conductance; skin disease |
Mutation functional classification
Loss of Function (LOF)
Nonsense or frameshift variants leading to truncated protein; associated with hearing loss.
Gain of Function (GOF)
Not reported for GJB5.
Dominant Negative (DN)
Missense mutations (e.g., p.Gly12Asp) that interfere with wild-type connexin oligomerization; linked to EKVP.
View complete mutation data：
Gene Ontology (GO)
| • gap junction (GO:0005922) | • gap junction channel activity (GO:0005243) |
| • cell communication (GO:0007154) | • plasma membrane (GO:0005886) |
| • cell-cell junction (GO:0005911) |
Pathways
• Gap junction trafficking and assembly (Reactome: R-HSA-190861)
• Connexin transport to the plasma membrane (Reactome: R-HSA-190840)
Protein Summary
Connexin 31.1 (Cx31.1) is a 271-amino acid transmembrane protein with four alpha-helical domains, forming hexameric connexons that dock with adjacent cells to create gap junction channels. It is highly expressed in stratified squamous epithelium and cochlear supporting cells, mediating ionic and metabolic coupling. Mutations in GJB5 alter channel gating, trafficking, or assembly, leading to skin disorders and hearing impairment.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| GJB5 Knockout HEK293 Cell Line | EDJ-KQ4713 | Human | 2709 | Details Get a Quote |
| GJB5 Knockout HCT 116 Cell Line | EDJ-KQ27433 | Human | 2709 | Details Get a Quote |
| GJB5 Knockout HeLa Cell Line | EDJ-KQ53350 | Human | 2709 | Details Get a Quote |
| GJB5 Knockout A-549 Cell Line | EDJ-KQ61829 | Human | 2709 | Details Get a Quote |
