TCAP: Titin-Cap / Telethonin
Sarcomeric Z-disc protein involved in muscle structure and signaling
Gene Information Card
| Symbol | TCAP |
|---|---|
| Full Name | Titin-Cap (Telethonin) |
| Gene Type | Protein coding |
| Chromosomal Location | 17q12 |
| NCBI Gene ID | 8557 ncbi.nlm.nih.gov/gene/8557 |
| Ensembl ID | ENSG00000173991 |
| UniProt ID | O15273 |
| OMIM ID | 604488 |
| HGNC ID | 11610 |
| Aliases | TELETHONIN, CMD1N, LGMD2G, T-CAP |
Description
The TCAP gene encodes telethonin (titin-cap), a sarcomeric protein localized to the Z-disc of striated muscle. It interacts with the N-terminus of titin and is essential for sarcomere assembly, stability, and mechanosensing. Mutations in TCAP cause limb-girdle muscular dystrophy type 2G (LGMD2G) and dilated cardiomyopathy (CMD1N).
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Limb-Girdle Muscular Dystrophy Type 2G (LGMD2G) | Loss-of-function mutations in TCAP disrupt sarcomere integrity, leading to progressive muscle weakness. | ClinVar, OMIM |
| Dilated Cardiomyopathy 1N (CMD1N) | TCAP mutations impair Z-disc mechanosensing, causing dilated cardiomyopathy with conduction defects. | ClinVar, OMIM |
| Hypertrophic Cardiomyopathy | Rare TCAP variants may contribute to hypertrophic cardiomyopathy via altered sarcomeric signaling. | ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Heart | 32.5 | High |
| Skeletal Muscle | 28.1 | High |
| Esophagus | 6.2 | Medium |
| Adipose Tissue | 1.1 | Low |
| Liver | 0.3 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Cardiomyocytes (iPS-derived) | 35.0 | High expression |
| Skeletal muscle myoblasts | 22.4 | High expression |
| HeLa | 0.5 | Low expression |
| HEK293 | 0.2 | Not detected |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.26C>T (p.Thr9Ile) | Missense | Rare | Impaired titin binding; associated with LGMD2G |
| c.137G>A (p.Arg46Gln) | Missense | Rare | Reduced sarcomeric localization; linked to dilated cardiomyopathy |
| c.1A>G (p.Met1Val) | Start loss | Rare | Loss of protein expression; pathogenic in LGMD2G |
| c.194delC (p.Pro65Leufs*19) | Frameshift | Rare | Premature truncation; loss of function |
Mutation functional classification
Loss of Function (LOF)
Most TCAP mutations (nonsense, frameshift, start loss) lead to loss of telethonin protein, disrupting Z-disc structure and causing LGMD2G.
Gain of Function (GOF)
No gain-of-function mutations reported for TCAP.
Dominant Negative (DN)
Some missense variants (e.g., p.Arg46Gln) may exert dominant-negative effects by interfering with titin binding, contributing to cardiomyopathy.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Striated Muscle Contraction (Reactome: R-HSA-390522)
• Sarcomere Organization (Reactome: R-HSA-525793)
Protein Summary
Telethonin (UniProt O15273) is a 167-amino acid sarcomeric protein that caps the N-terminus of titin at the Z-disc. It forms a complex with titin and other Z-disc proteins, contributing to sarcomere assembly and mechanotransduction. Telethonin is highly expressed in cardiac and skeletal muscle. Loss of telethonin leads to muscular dystrophy and cardiomyopathy.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| KRTCAP2 Knockout HEK293 Cell Line | EDJ-KQ4415 | Human | 200185 | Details Get a Quote |
| KRTCAP3 Knockout HEK293 Cell Line | EDJ-KQ4564 | Human | 200634 | Details Get a Quote |
| TCAP Knockout HEK293 Cell Line | EDJ-KQ6286 | Human | 8557 | Details Get a Quote |
| MATCAP1 Knockout HEK293 Cell Line | EDJ-KQ13417 | Human | 653319 | Details Get a Quote |
| MATCAP2 Knockout HEK293 Cell Line | EDJ-KQ14206 | Human | 23366 | Details Get a Quote |
| KRTCAP2 Knockout A-549 Cell Line | EDJ-KQ26941 | Human | 200185 | Details Get a Quote |
| KRTCAP2 Knockout HCT 116 Cell Line | EDJ-KQ26942 | Human | 200185 | Details Get a Quote |
| KRTCAP2 Knockout HeLa Cell Line | EDJ-KQ26943 | Human | 200185 | Details Get a Quote |
| KRTCAP3 Knockout HCT 116 Cell Line | EDJ-KQ27210 | Human | 200634 | Details Get a Quote |
| KRTCAP3 Knockout HeLa Cell Line | EDJ-KQ27211 | Human | 200634 | Details Get a Quote |
| MATCAP1 Knockout A-549 Cell Line | EDJ-KQ44158 | Human | 653319 | Details Get a Quote |
| MATCAP1 Knockout HCT 116 Cell Line | EDJ-KQ44160 | Human | 653319 | Details Get a Quote |
| MATCAP1 Knockout HeLa Cell Line | EDJ-KQ44161 | Human | 653319 | Details Get a Quote |
| MATCAP2 Knockout A-549 Cell Line | EDJ-KQ44162 | Human | 23366 | Details Get a Quote |
| MATCAP2 Knockout HCT 116 Cell Line | EDJ-KQ44163 | Human | 23366 | Details Get a Quote |
Displaying Records 1 To 15 Of 21 Records
