Seroatlas · Human Serome Atlas

RPS6KA3

Ribosomal protein S6 kinase alpha-3

Also known as: CLS, HU-3, KS6A3_HUMAN, MRX19, RSK2

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

Protein identityUniProt · HPA

UniProt accession
P51812
Gene
RPS6KA3
Ensembl
ENSG00000177189
Chromosome
X
Canonical length
740 aa
Protein class
Cancer-related genes, Disease related genes, Enzymes, Human disease related genes, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Nucleoplasm,Nucleoli,Cytosol

OverviewNCBI Gene

This gene encodes a member of the RSK (ribosomal S6 kinase) family of serine/threonine kinases. This kinase contains 2 non-identical kinase catalytic domains and phosphorylates various substrates, including members of the mitogen-activated kinase (MAPK) signalling pathway. The activity of this protein has been implicated in controlling cell growth and differentiation. Mutations in this gene have been associated with Coffin-Lowry syndrome (CLS). [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

740 residues, UniProt reviewed canonical sequence.

>P51812|RPS6KA3
     1  MPLAQLADPW QKMAVESPSD SAENGQQIMD EPMGEEEINP QTEEVSIKEI AITHHVKEGH
    61  EKADPSQFEL LKVLGQGSFG KVFLVKKISG SDARQLYAMK VLKKATLKVR DRVRTKMERD
   121  ILVEVNHPFI VKLHYAFQTE GKLYLILDFL RGGDLFTRLS KEVMFTEEDV KFYLAELALA
   181  LDHLHSLGII YRDLKPENIL LDEEGHIKLT DFGLSKESID HEKKAYSFCG TVEYMAPEVV
   241  NRRGHTQSAD WWSFGVLMFE MLTGTLPFQG KDRKETMTMI LKAKLGMPQF LSPEAQSLLR
   301  MLFKRNPANR LGAGPDGVEE IKRHSFFSTI DWNKLYRREI HPPFKPATGR PEDTFYFDPE
   361  FTAKTPKDSP GIPPSANAHQ LFRGFSFVAI TSDDESQAMQ TVGVHSIVQQ LHRNSIQFTD
   421  GYEVKEDIGV GSYSVCKRCI HKATNMEFAV KIIDKSKRDP TEEIEILLRY GQHPNIITLK
   481  DVYDDGKYVY VVTELMKGGE LLDKILRQKF FSEREASAVL FTITKTVEYL HAQGVVHRDL
   541  KPSNILYVDE SGNPESIRIC DFGFAKQLRA ENGLLMTPCY TANFVAPEVL KRQGYDAACD
   601  IWSLGVLLYT MLTGYTPFAN GPDDTPEEIL ARIGSGKFSL SGGYWNSVSD TAKDLVSKML
   661  HVDPHQRLTA ALVLRHPWIV HWDQLPQYQL NRQDAPHLVK GAMAATYSAL NRNQSPVLEP
   721  VGRSTLAQRR GIKKITSTAL

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against RPS6KA3 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
56 nTPM

Expression across tissuesHPA

Tissue

  • parathyroid gland: 56 nTPM
  • skeletal muscle: 51 nTPM
  • liver: 42 nTPM
  • tongue: 38 nTPM
  • urinary bladder: 32 nTPM
  • appendix: 32 nTPM

Single-cell type

  • neutrophils: 1,335 nCPM
  • innate lymphoid cells: 586 nCPM
  • ocular epithelial cells: 575 nCPM
  • myonuclei: 446 nCPM
  • urothelial cells: 400 nCPM
  • alveolar cells type 2: 372 nCPM

Immune cell

  • basophil: 12 nTPM
  • MAIT T-cell: 8.2 nTPM
  • eosinophil: 7.9 nTPM
  • plasmacytoid DC: 6.7 nTPM
  • NK-cell: 6.6 nTPM
  • non-classical monocyte: 6 nTPM

Brain region

  • cerebral cortex: 31 nTPM
  • cerebellum: 31 nTPM
  • thalamus: 28 nTPM
  • basal ganglia: 26 nTPM
  • midbrain: 26 nTPM
  • hypothalamus: 24 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about RPS6KA3.

Disease | AllUniProt

Conditions RPS6KA3 is implicated in, by any mechanism.

  • Coffin-Lowry syndrome (CLS) MIM:303600
  • Intellectual developmental disorder, X-linked 19 (XLID19) MIM:300844

Disease | GeneticClinVar

165 pathogenic / likely-pathogenic of 739 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

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)
0.09
gnomAD pLI
1
gnomAD missense Z
4.52
DepMap mean gene effect
-0.15
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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 RPS6KA3 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 RPS6KA3 as an antibody target. Whether an autoantibody or antibody against RPS6KA3 could matter depends on whether native RPS6KA3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

RPS6KA3 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 RPS6KA3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/RPS6KA3. 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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