SNRPA
Small Nuclear Ribonucleoprotein Polypeptide A
Gene Information Card
| Symbol | SNRPA |
|---|---|
| Full Name | Small Nuclear Ribonucleoprotein Polypeptide A |
| Gene Type | protein-coding |
| Chromosomal Location | 19q13.2 |
| NCBI Gene ID | 6626 ncbi.nlm.nih.gov/gene/6626 |
| Ensembl ID | ENSG00000104879 |
| UniProt ID | P09012 |
| OMIM ID | 182280 |
| HGNC ID | 11151 |
| Aliases | U1A, U1-A, U1 snRNP A, Mud1 |
Description
SNRPA encodes the U1 small nuclear ribonucleoprotein A (U1A) protein, a component of the U1 snRNP complex essential for pre-mRNA splicing. The protein binds directly to stem-loop II of U1 snRNA and is involved in spliceosome assembly. Autoantibodies against SNRPA are associated with systemic lupus erythematosus and mixed connective tissue disease.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Systemic Lupus Erythematosus | Autoantibodies targeting U1A protein contribute to immune complex formation and tissue damage | OMIM:152700, ClinVar |
| Mixed Connective Tissue Disease | Anti-U1 RNP antibodies including anti-U1A are diagnostic markers | OMIM:613625, ClinVar |
| Spliceosome-related Retinitis Pigmentosa | Mutations in spliceosome components can cause retinal degeneration; SNRPA variants are rare but implicated | OMIM:268000, ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Testis | 28.5 | High |
| Lymph node | 22.3 | High |
| Spleen | 20.1 | High |
| Brain | 15.4 | Medium |
| Heart | 12.8 | Medium |
| Liver | 9.2 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK 293 | 35.2 | High expression in embryonic kidney cells |
| HeLa | 30.8 | High expression in cervical cancer cells |
| K562 | 25.6 | Moderate expression in leukemia cells |
| HepG2 | 18.4 | Moderate expression in liver cancer cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.64G>A (p.Gly22Arg) | Missense | <0.01% | Unknown; rare variant in population databases |
| c.287A>G (p.Asn96Ser) | Missense | <0.01% | Unknown; predicted benign |
| c.421C>T (p.Arg141Trp) | Missense | <0.01% | Unknown; predicted possibly damaging |
Mutation functional classification
Loss of Function (LOF)
No confirmed loss-of-function mutations reported in disease; likely essential for splicing.
Gain of Function (GOF)
Not described.
Dominant Negative (DN)
Not described.
View complete mutation data：
Gene Ontology (GO)
| • RNA binding (GO:0003723) | • U1 snRNA binding (GO:0030619) |
| • via spliceosome (GO:0000398) | • spliceosomal complex assembly (GO:0000245) |
| • nucleus (GO:0005634) | • U1 snRNP (GO:0005685) |
Pathways
• Spliceosome (KEGG hsa03040)
• Processing of Capped Intron-Containing Pre-mRNA (Reactome R-HSA-72203)
• mRNA Splicing - Major Pathway (Reactome R-HSA-72163)
Protein Summary
The SNRPA protein (U1A) is a 282-amino acid RNA-binding protein that contains two RNA recognition motifs (RRMs). It specifically binds to stem-loop II of U1 snRNA and is critical for U1 snRNP stability and function in 5' splice site recognition. U1A also autoregulates its own expression by binding to its pre-mRNA. The protein is a common autoantigen in systemic lupus erythematosus.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SNRPA Knockout HEK293 Cell Line | EDJ-KQ5810 | Human | 6626 | Details Get a Quote |
| SNRPA Knockout A-549 Cell Line | EDJ-KQ27971 | Human | 6626 | Details Get a Quote |
| SNRPA Knockout HCT 116 Cell Line | EDJ-KQ29231 | Human | 6626 | Details Get a Quote |
| SNRPA Knockout HeLa Cell Line | EDJ-KQ29232 | Human | 6626 | Details Get a Quote |
