GJC1 (Gap Junction Protein Gamma 1)
A key cardiac connexin involved in electrical coupling and arrhythmia susceptibility
Gene Information Card
| Symbol | GJC1 |
|---|---|
| Full Name | gap junction protein gamma 1 |
| Gene Type | protein-coding |
| Chromosomal Location | 17q21.31 |
| NCBI Gene ID | 10052 ncbi.nlm.nih.gov/gene/10052 |
| Ensembl ID | ENSG00000182963 |
| UniProt ID | P36383 |
| OMIM ID | 608655 |
| HGNC ID | 4280 |
| Aliases | GJA7, Cx45, connexin 45 |
Description
GJC1 encodes connexin 45 (Cx45), a member of the connexin family of gap junction proteins. Connexins form hexameric hemichannels (connexons) that dock with counterparts on adjacent cells to create intercellular channels. Cx45 is predominantly expressed in cardiac tissues, particularly in the atrioventricular node and ventricles, where it mediates electrical impulse propagation. Mutations in GJC1 are associated with cardiac conduction defects and arrhythmias.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Atrial fibrillation | Altered gap junction function leads to abnormal electrical coupling and reentrant circuits | ClinVar, PMID: 23571588 |
| Progressive familial heart block type 1A | Loss-of-function mutations impair conduction through the atrioventricular node | OMIM #608655, PMID: 20817017 |
| Sudden cardiac death | Disrupted Cx45 channels predispose to lethal arrhythmias | ClinVar, PMID: 25351510 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Heart | 12.5 | Medium |
| Smooth muscle | 5.2 | Low |
| Brain | 3.8 | Low |
| Placenta | 2.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Cardiomyocytes | 15.0 | Primary cardiac cells |
| HeLa | 0.5 | Low expression |
| HEK293 | 0.3 | Minimal endogenous expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.412C>T (p.Arg138Cys) | Missense | <0.01% | Reduced channel conductance; associated with atrial fibrillation |
| c.35G>A (p.Gly12Asp) | Missense | <0.01% | Dominant-negative effect; linked to heart block |
| c.1A>G (p.Met1Val) | Start loss | <0.01% | Loss of protein expression; severe conduction defect |
Mutation functional classification
Loss of Function (LOF)
Missense and start-loss mutations reduce or abolish channel activity, impairing intercellular communication.
Gain of Function (GOF)
Not reported for GJC1.
Dominant Negative (DN)
p.Gly12Asp and p.Arg138Cys mutants interfere with wild-type connexin assembly, reducing overall gap junction function.
View complete mutation data：
Gene Ontology (GO)
| • gap junction channel activity | • cell-cell signaling |
| • cardiac conduction | • protein homooligomerization |
| • transmembrane transport |
Pathways
• Gap junction trafficking and assembly
• Cardiac conduction
• Cell-cell communication
Protein Summary
Connexin 45 is a 396-amino acid transmembrane protein with four alpha-helical domains, two extracellular loops, and a cytoplasmic C-terminus. It forms low-conductance gap junction channels that preferentially pass small molecules and ions. In the heart, Cx45 is essential for coordinated contraction and electrical synchronization.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| GJC1 Knockout HEK293 Cell Line | EDJ-KQ3385 | Human | 10052 | Details Get a Quote |
| GJC1 Knockout A-549 Cell Line | EDJ-KQ25076 | Human | 10052 | Details Get a Quote |
| GJC1 Knockout HCT 116 Cell Line | EDJ-KQ25077 | Human | 10052 | Details Get a Quote |
| GJC1 Knockout HeLa Cell Line | EDJ-KQ25078 | Human | 10052 | Details Get a Quote |
