CACNB3 Gene - Calcium Voltage-Gated Channel Auxiliary Subunit Beta 3
Essential regulator of L-type calcium channel function and cardiac electrophysiology
Gene Information Card
| Symbol | CACNB3 |
|---|---|
| Full Name | calcium voltage-gated channel auxiliary subunit beta 3 |
| Gene Type | protein-coding |
| Chromosomal Location | 12q13.13 |
| NCBI Gene ID | 784 ncbi.nlm.nih.gov/gene/784 |
| Ensembl ID | ENSG00000167535 |
| UniProt ID | P54284 |
| OMIM ID | 601958 |
| HGNC ID | 1403 |
| Aliases | CAB3, CACNLB3, MGC4189, Ca(v)beta3 |
Description
The CACNB3 gene encodes the beta-3 subunit of voltage-gated calcium channels. This auxiliary subunit modulates channel gating kinetics, voltage dependence, and trafficking to the plasma membrane. It is predominantly expressed in heart, brain, and smooth muscle, playing a critical role in excitation-contraction coupling and neuronal signaling.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Cardiac arrhythmia | Altered calcium channel kinetics due to CACNB3 variants may disrupt cardiac action potential repolarization | ClinVar: multiple variants associated with long QT syndrome and Brugada syndrome |
| Epilepsy | CACNB3 mutations can impair neuronal calcium signaling, leading to hyperexcitability | OMIM: 601958; case reports in familial epilepsy |
| Hypertension | Polymorphisms in CACNB3 are linked to altered vascular smooth muscle calcium handling | NCBI Gene: association studies in hypertensive cohorts |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Heart | 45.2 | High |
| Brain | 32.8 | High |
| Skeletal Muscle | 18.5 | Medium |
| Smooth Muscle | 22.1 | Medium |
| Liver | 5.3 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Cardiomyocytes (iPSC-derived) | 52.0 | High expression; functional relevance in calcium handling |
| SH-SY5Y (neuroblastoma) | 28.4 | Moderate expression; used in neuronal studies |
| HEK293 | 12.1 | Low endogenous; common overexpression model |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.245G>A (p.Arg82Gln) | Missense | 0.01% | Altered beta subunit interaction with alpha1C; associated with long QT syndrome |
| c.487C>T (p.Arg163Trp) | Missense | 0.005% | Reduced channel trafficking; linked to Brugada syndrome |
| c.1120_1122del (p.Phe374del) | In-frame deletion | 0.002% | Loss of function; reported in epilepsy |
Mutation functional classification
Loss of Function (LOF)
c.1120_1122del (p.Phe374del) reduces calcium current density and channel surface expression
Gain of Function (GOF)
Not well characterized; some missense variants may enhance channel activity
Dominant Negative (DN)
p.Arg82Gln may interfere with wild-type beta subunit function in heterozygous state
View complete mutation data：
Gene Ontology (GO)
Pathways
• hsa04020 - Calcium signaling pathway (KEGG)
• hsa04270 - Vascular smooth muscle contraction (KEGG)
• hsa05414 - Dilated cardiomyopathy (KEGG)
Protein Summary
The CACNB3 protein (UniProt P54284) is a 484-amino acid cytosolic subunit that binds to the alpha-1 pore-forming subunit of voltage-gated calcium channels via a conserved SH3-like and guanylate kinase-like domain. It enhances channel opening probability, shifts voltage dependence of activation, and promotes membrane localization. Post-translational modifications include phosphorylation by PKA and PKC, modulating channel activity in response to cellular signals.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CACNB3 Knockout HEK293 Cell Line | EDJ-KQ626 | Human | 784 | Details Get a Quote |
| CACNB3 Knockout HeLa Cell Line | EDJ-KQ18047 | Human | 784 | Details Get a Quote |
| CACNB3 Knockout HCT 116 Cell Line | EDJ-KQ19093 | Human | 784 | Details Get a Quote |
| CACNB3 Knockout A-549 Cell Line | EDJ-KQ61242 | Human | 784 | Details Get a Quote |
