CNTN2 Gene (Contactin 2)
Axonal glycoprotein involved in neural development and epilepsy
Gene Information Card
| Symbol | CNTN2 |
|---|---|
| Full Name | Contactin 2 |
| Gene Type | Protein coding |
| Chromosomal Location | 1q32.1 |
| NCBI Gene ID | 6900 ncbi.nlm.nih.gov/gene/6900 |
| Ensembl ID | ENSG00000117461 |
| UniProt ID | Q02246 |
| OMIM ID | 190197 |
| HGNC ID | 2172 |
| Aliases | AXF, TAG-1, TAX1 |
Description
CNTN2 encodes Contactin 2, a glycosylphosphatidylinositol (GPI)-anchored neuronal cell adhesion molecule of the immunoglobulin superfamily. It is primarily expressed in the nervous system and plays a critical role in axonal guidance, fasciculation, and synaptic organization. CNTN2 interacts with receptor protein tyrosine phosphatases and contributes to the formation of the juxtaparanodal region of myelinated axons. Mutations in CNTN2 are associated with autosomal recessive myoclonic epilepsy and neurodevelopmental disorders.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Myoclonic epilepsy, familial, 5 (EPM5) | Loss-of-function mutations impair axonal adhesion and neuronal excitability regulation | OMIM #616421; ClinVar |
| Neurodevelopmental disorder with epilepsy and intellectual disability | Homozygous or compound heterozygous CNTN2 variants disrupt protein function | ClinVar; PubMed studies |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | High |
| Cerebellum | 18.3 | High |
| Cerebral cortex | 10.1 | Medium |
| Spinal cord | 8.4 | Medium |
| Testis | 1.2 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| SH-SY5Y (neuroblastoma) | 15.0 | Neuronal model |
| U-87 MG (glioblastoma) | 6.5 | Glial-derived |
| HEK293 (embryonic kidney) | 0.8 | Non-neuronal control |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.100C>T (p.Arg34Ter) | Nonsense | Rare | Loss of function; premature truncation |
| c.473G>A (p.Arg158Gln) | Missense | Rare | Impaired protein folding and trafficking |
| c.1222_1223del (p.Leu408ValfsTer12) | Frameshift | Rare | Loss of function; truncated protein |
Mutation functional classification
Loss of Function (LOF)
Most reported CNTN2 mutations are loss-of-function, leading to reduced or absent protein expression, impaired axonal adhesion, and altered neuronal network excitability.
Gain of Function (GOF)
No gain-of-function mutations have been reported for CNTN2.
Dominant Negative (DN)
No dominant-negative mechanisms have been described for CNTN2.
View complete mutation data：
Gene Ontology (GO)
| • cell adhesion (GO:0007155) | • axon guidance (GO:0007411) |
| • plasma membrane (GO:0005886) | • anchored component of membrane (GO:0031225) |
| • chemical synaptic transmission (GO:0007268) |
Pathways
• Cell adhesion molecules (CAMs) – KEGG hsa04514
• Neuroactive ligand-receptor interaction – KEGG hsa04080
• Axon guidance – Reactome R-HSA-422475
Protein Summary
Contactin 2 is a 130 kDa GPI-anchored glycoprotein expressed on the surface of neurons. It consists of six immunoglobulin-like domains and four fibronectin type III repeats. The protein mediates homophilic and heterophilic cell adhesion, interacts with contactin-associated protein (CNTNAP2) and receptor tyrosine phosphatases, and is essential for the organization of the juxtaparanodal region in myelinated axons. It also modulates voltage-gated potassium channel clustering and neuronal excitability.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CNTN2 Knockout HEK293 Cell Line | EDJ-KQ2809 | Human | 6900 | Details Get a Quote |
| CNTN2 Knockout HeLa Cell Line | EDJ-KQ54614 | Human | 6900 | Details Get a Quote |
| CNTN2 Knockout A-549 Cell Line | EDJ-KQ63095 | Human | 6900 | Details Get a Quote |
| CNTN2 Knockout HCT 116 Cell Line | EDJ-KQ71568 | Human | 6900 | Details Get a Quote |
