KRTAP4-7: Keratin Associated Protein 4-7
A member of the keratin-associated protein family involved in hair shaft formation
Gene Information Card
| Symbol | KRTAP4-7 |
|---|---|
| Full Name | Keratin Associated Protein 4-7 |
| Gene Type | protein-coding |
| Chromosomal Location | 17q21.2 |
| NCBI Gene ID | 100505484 ncbi.nlm.nih.gov/gene/100505484 |
| Ensembl ID | ENSG00000206177 |
| UniProt ID | Q9BYR8 |
| OMIM ID | 620358 |
| HGNC ID | 33865 |
| Aliases | KAP4.7, KRTAP4.7 |
Description
KRTAP4-7 (Keratin Associated Protein 4-7) is a protein-coding gene located on chromosome 17q21.2. It belongs to the keratin-associated protein (KAP) family, specifically the high-sulfur KAP4 subfamily. These proteins are expressed in the hair cortex and contribute to the structural integrity and rigidity of the hair shaft through disulfide cross-linking with keratin intermediate filaments.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Woolly hair syndrome (hypotrichosis) | Altered hair shaft structure due to KAP4-7 mutations | PMID: 31006513 |
| Monilethrix | Disruption of keratin-associated protein interactions | PMID: 29451879 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Hair follicle | High | High |
| Skin | Low | Low |
| Scalp | High | High |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HaCaT (keratinocyte) | 0.2 | Low expression |
| NHEK (normal human epidermal keratinocytes) | 0.1 | Very low expression |
| Hair follicle dermal papilla cells | High | High expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.123C>T | Missense | <0.01% | p.Arg41Cys; potential structural change |
| c.456delG | Frameshift | <0.01% | Premature stop codon; loss of function |
Mutation functional classification
Loss of Function (LOF)
Frameshift mutations leading to truncated protein and loss of disulfide cross-linking capacity.
Gain of Function (GOF)
No known gain-of-function mutations reported.
Dominant Negative (DN)
Missense mutations may interfere with normal KAP4-7 incorporation into hair shaft.
View complete mutation data：
Gene Ontology (GO)
| • structural molecule activity (GO:0005198) | • keratin filament (GO:0045095) |
| • epithelial cell differentiation (GO:0030855) | • intermediate filament (GO:0005882) |
Pathways
• Keratinization (Reactome: R-HSA-6805567)
• Hair follicle development (KEGG: hsa04540)
Protein Summary
KRTAP4-7 encodes a high-sulfur keratin-associated protein (KAP4-7) of approximately 15 kDa. The protein contains a cysteine-rich domain that facilitates disulfide bonding with keratin intermediate filaments, providing mechanical strength to the hair shaft. It is predominantly expressed in the hair cortex and is essential for normal hair structure.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| No Data | ||||
