SPRR2A (Small Proline Rich Protein 2A)
A cornified envelope precursor protein involved in epidermal barrier function and squamous differentiation.
Gene Information Card
| Symbol | SPRR2A |
|---|---|
| Full Name | Small Proline Rich Protein 2A |
| Gene Type | Protein coding |
| Chromosomal Location | 1q21.3 |
| NCBI Gene ID | 6700 ncbi.nlm.nih.gov/gene/6700 |
| Ensembl ID | ENSG00000162692 |
| UniProt ID | P35326 |
| OMIM ID | 182268 |
| HGNC ID | 11263 |
| Aliases | SPRR2, SPRR2A |
Description
SPRR2A encodes a member of the small proline-rich protein family, which are components of the cornified cell envelope in stratified squamous epithelia. This protein is cross-linked by transglutaminases during terminal differentiation of keratinocytes, contributing to the barrier function of the epidermis. SPRR2A expression is upregulated in psoriatic skin and certain squamous cell carcinomas.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Psoriasis | Upregulated in lesional skin; contributes to altered cornified envelope formation | NCBI Gene, OMIM |
| Squamous cell carcinoma (various sites) | Overexpression associated with squamous differentiation and tumor progression | COSMIC, NCBI Gene |
| Atopic dermatitis | Altered expression may affect epidermal barrier integrity | NCBI Gene |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Skin | 127.4 | High |
| Esophagus | 45.2 | Medium |
| Oral mucosa | 38.1 | Medium |
| Vagina | 22.8 | Medium |
| Lung | 1.2 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HaCaT (keratinocyte) | 156.3 | High expression |
| A431 (epidermoid carcinoma) | 89.7 | High expression |
| NCI-H520 (squamous lung) | 34.5 | Medium expression |
| HeLa (cervical) | 0.8 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Missense | <0.01% | Likely loss of start codon; functional impact unknown |
| c.67C>T (p.Pro23Ser) | Missense | <0.01% | Rare variant; no known disease association |
| c.148G>A (p.Gly50Arg) | Missense | <0.01% | Reported in COSMIC; uncertain significance |
Mutation functional classification
Loss of Function (LOF)
No confirmed loss-of-function mutations reported in germline or somatic databases.
Gain of Function (GOF)
No confirmed gain-of-function mutations reported.
Dominant Negative (DN)
No evidence for dominant-negative effects.
View complete mutation data：
Gene Ontology (GO)
| • cornified envelope | • keratinocyte differentiation |
| • structural molecule activity | • epidermis development |
| • cross-linking |
Pathways
• Keratinocyte differentiation
• Formation of the cornified envelope
Protein Summary
SPRR2A is a 73-amino acid protein (8.5 kDa) rich in proline and glutamine, localized to the cytoplasm and plasma membrane. It serves as a substrate for transglutaminase 1, 3, and 5, forming isopeptide bonds that stabilize the cornified envelope. The protein is expressed primarily in stratified squamous epithelia and is induced during terminal differentiation.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SPRR2A Knockout HEK293 Cell Line | EDJ-KQ50651 | Human | 6700 | Details Get a Quote |
| SPRR2A Knockout HeLa Cell Line | EDJ-KQ54552 | Human | 6700 | Details Get a Quote |
| SPRR2A Knockout A-549 Cell Line | EDJ-KQ63036 | Human | 6700 | Details Get a Quote |
| SPRR2A Knockout HCT 116 Cell Line | EDJ-KQ71512 | Human | 6700 | Details Get a Quote |
