Seroatlas · Human Serome Atlas

RPS4X

Small ribosomal subunit protein eS4, X isoform

Also known as: CCG2, DXS306, FLJ40595, RPS4, RS4X_HUMAN, S4, SCAR, SCR10

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

Protein identityUniProt · HPA

UniProt accession
P62701
Gene
RPS4X
Ensembl
ENSG00000198034
Chromosome
X
Canonical length
263 aa
Protein class
Plasma proteins, Predicted intracellular proteins, Ribosomal proteins

OverviewNCBI Gene

Cytoplasmic ribosomes, organelles that catalyze protein synthesis, consist of a small 40S subunit and a large 60S subunit. Together these subunits are composed of 4 RNA species and approximately 80 structurally distinct proteins. This gene encodes ribosomal protein S4, a component of the 40S subunit. Ribosomal protein S4 is the only ribosomal protein known to be encoded by more than one gene, namely this gene and ribosomal protein S4, Y-linked (RPS4Y). The 2 isoforms encoded by these genes are not identical, but are functionally equivalent. Ribosomal protein S4 belongs to the S4E family of ribosomal proteins. This gene is not subject to X-inactivation. It has been suggested that haploinsufficiency of the ribosomal protein S4 genes plays a role in Turner syndrome; however, this hypothesis is controversial. As is typical for genes encoding ribosomal proteins, there are multiple processed pseudogenes of this gene dispersed through the genome. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

263 residues, UniProt reviewed canonical sequence.

>P62701|RPS4X
     1  MARGPKKHLK RVAAPKHWML DKLTGVFAPR PSTGPHKLRE CLPLIIFLRN RLKYALTGDE
    61  VKKICMQRFI KIDGKVRTDI TYPAGFMDVI SIDKTGENFR LIYDTKGRFA VHRITPEEAK
   121  YKLCKVRKIF VGTKGIPHLV THDARTIRYP DPLIKVNDTI QIDLETGKIT DFIKFDTGNL
   181  CMVTGGANLG RIGVITNRER HPGSFDVVHV KDANGNSFAT RLSNIFVIGK GNKPWISLPR
   241  GKGIRLTIAE ERDKRLAAKQ SSG

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against RPS4X 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)
0.3
Highest tissue expression
2,239 nTPM

Expression across tissuesHPA

Tissue

  • ovary: 2,239 nTPM
  • pancreas: 1,707 nTPM
  • skin: 1,489 nTPM
  • cervix: 1,376 nTPM
  • epididymis: 1,355 nTPM
  • breast: 1,328 nTPM

Single-cell type

  • decidual stromal cells: 13,757 nCPM
  • esophageal suprabasal cells: 12,384 nCPM
  • esophageal basal cells: 10,837 nCPM
  • breast secretory cells: 10,089 nCPM
  • extravillous trophoblasts: 9,225 nCPM
  • epididymal principal cells: 9,131 nCPM

Immune cell

  • total PBMC: 3,740 nTPM
  • naive CD4 T-cell: 2,198 nTPM
  • memory B-cell: 2,018 nTPM
  • naive CD8 T-cell: 1,792 nTPM
  • naive B-cell: 1,790 nTPM
  • memory CD4 T-cell: 1,784 nTPM

Brain region

  • spinal cord: 189 nTPM
  • hypothalamus: 187 nTPM
  • white matter: 175 nTPM
  • medulla oblongata: 165 nTPM
  • thalamus: 159 nTPM
  • basal ganglia: 157 nTPM

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)
0.35
gnomAD pLI
0.93
gnomAD missense Z
2.29
DepMap mean gene effect
-2.32
DepMap dependency class
pan

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 RPS4X 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 RPS4X as an antibody target. Whether an autoantibody or antibody against RPS4X could matter depends on whether native RPS4X is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

RPS4X 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 RPS4X as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/RPS4X. 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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