GJD2 (Gap Junction Protein Delta 2)
Key regulator of electrical synapses and retinal signaling
Gene Information Card
| Symbol | GJD2 |
|---|---|
| Full Name | Gap junction protein delta 2 |
| Gene Type | Protein coding |
| Chromosomal Location | 15q14 |
| NCBI Gene ID | 5733 ncbi.nlm.nih.gov/gene/5733 |
| Ensembl ID | ENSG00000137868 |
| UniProt ID | Q9UKL4 |
| OMIM ID | 607058 |
| HGNC ID | 4287 |
| Aliases | CX36, GJA9, connexin-36 |
Description
GJD2 encodes connexin 36 (Cx36), a member of the connexin family of gap junction proteins. Connexin 36 forms intercellular channels that mediate electrical synapses, particularly in neurons and pancreatic beta cells. It is critical for synchronous firing in the retina and brain, and for insulin secretion.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Retinal dystrophy | Loss of Cx36 disrupts electrical coupling between retinal neurons, impairing visual signal processing. | ClinVar, OMIM |
| Diabetes mellitus (type 2) | Reduced Cx36 expression in pancreatic beta cells alters insulin secretion dynamics. | NCBI Gene, PubMed |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | Medium |
| Retina | 45.2 | High |
| Pancreas | 8.3 | Low |
| Testis | 3.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| SH-SY5Y (neuroblastoma) | 15.0 | Neuronal model |
| ARPE-19 (retinal pigment epithelium) | 22.4 | Retinal cell line |
| MIN6 (pancreatic beta cell) | 9.8 | Insulin-secreting cell |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.94C>T (p.Arg32Trp) | Missense | Rare | Alters channel conductance; associated with retinal dysfunction |
| c.227G>A (p.Gly76Asp) | Missense | Rare | Reduced gap junction coupling; linked to diabetes |
Mutation functional classification
Loss of Function (LOF)
Missense mutations (e.g., p.Arg32Trp) reduce or abolish gap junction channel activity, impairing electrical coupling.
Gain of Function (GOF)
No gain-of-function mutations reported for GJD2.
Dominant Negative (DN)
Some missense variants may exert dominant-negative effects by forming non-functional heteromeric channels.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Gap junction trafficking and regulation (Reactome: R-HSA-190828)
• Electrical synapse transmission (KEGG: hsa04540)
Protein Summary
Connexin 36 (Cx36) is a 321-amino acid transmembrane protein that oligomerizes into hexameric hemichannels (connexons). Two hemichannels from adjacent cells dock to form a gap junction channel, allowing direct electrical and metabolic coupling. Cx36 is predominantly expressed in neurons and pancreatic beta cells, where it coordinates electrical activity and insulin release.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| GJD2 Knockout HEK293 Cell Line | EDJ-KQ13603 | Human | 57369 | Details Get a Quote |
| GJD2 Knockout HeLa Cell Line | EDJ-KQ56830 | Human | 57369 | Details Get a Quote |
| GJD2 Knockout A-549 Cell Line | EDJ-KQ65340 | Human | 57369 | Details Get a Quote |
| GJD2 Knockout HCT 116 Cell Line | EDJ-KQ73779 | Human | 57369 | Details Get a Quote |
