Seroatlas · Human Serome Atlas

SNRPA

U1 small nuclear ribonucleoprotein A

Also known as: Mud1, SNRPA_HUMAN, U1-A, U1A

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P09012
Gene
SNRPA
Ensembl
ENSG00000077312
Chromosome
19
Canonical length
282 aa
Protein class
Plasma proteins, Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

The protein encoded by this gene associates with stem loop II of the U1 small nuclear ribonucleoprotein, which binds the 5' splice site of precursor mRNAs and is required for splicing. The encoded protein autoregulates itself by polyadenylation inhibition of its own pre-mRNA via dimerization and has been implicated in the coupling of splicing and polyadenylation. [provided by RefSeq, Oct 2010]

Canonical amino-acid sequenceUniProt

282 residues, UniProt reviewed canonical sequence.

>P09012|SNRPA
     1  MAVPETRPNH TIYINNLNEK IKKDELKKSL YAIFSQFGQI LDILVSRSLK MRGQAFVIFK
    61  EVSSATNALR SMQGFPFYDK PMRIQYAKTD SDIIAKMKGT FVERDRKREK RKPKSQETPA
   121  TKKAVQGGGA TPVVGAVQGP VPGMPPMTQA PRIMHHMPGQ PPYMPPPGMI PPPGLAPGQI
   181  PPGAMPPQQL MPGQMPPAQP LSENPPNHIL FLTNLPEETN ELMLSMLFNQ FPGFKEVRLV
   241  PGRHDIAFVE FDNEVQAGAA RDALQGFKIT QNNAMKISFA KK

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SNRPA can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Intracellular
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.45
Highest tissue expression
83 nTPM

Expression across tissuesHPA

Tissue

  • ovary: 83 nTPM
  • spleen: 77 nTPM
  • blood vessel: 77 nTPM
  • cervix: 71 nTPM
  • endometrium: 66 nTPM
  • thyroid gland: 66 nTPM

Single-cell type

  • extravillous trophoblasts: 151 nCPM
  • migrating cytotrophoblasts: 144 nCPM
  • esophageal basal cells: 141 nCPM
  • cytotrophoblasts: 111 nCPM
  • alveolar cells type 2: 102 nCPM
  • epididymal basal cells: 99 nCPM

Immune cell

  • myeloid DC: 57 nTPM
  • plasmacytoid DC: 35 nTPM
  • memory CD8 T-cell: 32 nTPM
  • intermediate monocyte: 32 nTPM
  • T-reg: 32 nTPM
  • naive CD4 T-cell: 30 nTPM

Brain region

  • basal ganglia: 37 nTPM
  • choroid plexus: 36 nTPM
  • hypothalamus: 36 nTPM
  • midbrain: 33 nTPM
  • pons: 33 nTPM
  • medulla oblongata: 33 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about SNRPA.

Disease | GeneticClinVar

2 pathogenic / likely-pathogenic of 47 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Spliceosomepathy

Disease | ImmuneIEDB

Conditions an epitope on SNRPA was assayed in.

Disease | AutoantibodyPubMed

Conditions in which antibodies against SNRPA are reported. Each links to that disease's full target list.

ReferencesPubMed · IEDB

Publications for SNRPA from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

11 publications

Show 6 more

Reference: B cellIEDB

10 publications

Show 5 more

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. IEDB — curated epitope assays from the Immune Epitope Database (Vita et al., Nucleic Acids Research 2019). Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.39
gnomAD pLI
0
gnomAD missense Z
1.75
DepMap mean gene effect
-0.37
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of SNRPA in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SNRPA as an antibody target. Whether an autoantibody or antibody against SNRPA could matter depends on whether native SNRPA is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SNRPA is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label SNRPA as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SNRPA. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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