Seroatlas · Human Serome Atlas

MAPK3

Mitogen-activated protein kinase 3

Also known as: ERK1, MK03_HUMAN, p44erk1, p44mapk, PRKM3

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

Protein identityUniProt · HPA

UniProt accession
P27361
Gene
MAPK3
Ensembl
ENSG00000102882
Chromosome
16
Canonical length
379 aa
Protein class
Cancer-related genes, Enzymes, FDA approved drug targets, Predicted intracellular proteins, RAS pathway related proteins
Subcellular location
Nucleoplasm,Microtubules,Primary cilium,Primary cilium tip,Basal body

OverviewNCBI Gene

The protein encoded by this gene is a member of the MAP kinase family. MAP kinases, also known as extracellular signal-regulated kinases (ERKs), act in a signaling cascade that regulates various cellular processes such as proliferation, differentiation, and cell cycle progression in response to a variety of extracellular signals. This kinase is activated by upstream kinases, resulting in its translocation to the nucleus where it phosphorylates nuclear targets. Alternatively spliced transcript variants encoding different protein isoforms have been described. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

379 residues, UniProt reviewed canonical sequence.

>P27361|MAPK3
     1  MAAAAAQGGG GGEPRRTEGV GPGVPGEVEM VKGQPFDVGP RYTQLQYIGE GAYGMVSSAY
    61  DHVRKTRVAI KKISPFEHQT YCQRTLREIQ ILLRFRHENV IGIRDILRAS TLEAMRDVYI
   121  VQDLMETDLY KLLKSQQLSN DHICYFLYQI LRGLKYIHSA NVLHRDLKPS NLLINTTCDL
   181  KICDFGLARI ADPEHDHTGF LTEYVATRWY RAPEIMLNSK GYTKSIDIWS VGCILAEMLS
   241  NRPIFPGKHY LDQLNHILGI LGSPSQEDLN CIINMKARNY LQSLPSKTKV AWAKLFPKSD
   301  SKALDLLDRM LTFNPNKRIT VEEALAHPYL EQYYDPTDEP VAEEPFTFAM ELDDLPKERL
   361  KELIFQETAR FQPGVLEAP

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MAPK3 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
Cell surface
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.27
Highest tissue expression
233 nTPM

Expression across tissuesHPA

Tissue

  • amygdala: 233 nTPM
  • cerebral cortex: 223 nTPM
  • basal ganglia: 154 nTPM
  • hippocampal formation: 141 nTPM
  • esophagus: 126 nTPM
  • midbrain: 120 nTPM

Single-cell type

  • esophageal apical cells: 543 nCPM
  • early spermatids: 326 nCPM
  • colonocytes: 269 nCPM
  • late spermatids: 230 nCPM
  • enterocytes: 226 nCPM
  • goblet cells: 190 nCPM

Immune cell

  • eosinophil: 49 nTPM
  • neutrophil: 22 nTPM
  • T-reg: 6.6 nTPM
  • basophil: 6.3 nTPM
  • classical monocyte: 5.1 nTPM
  • intermediate monocyte: 3.7 nTPM

Brain region

  • cerebral cortex: 250 nTPM
  • amygdala: 248 nTPM
  • basal ganglia: 211 nTPM
  • midbrain: 191 nTPM
  • pons: 177 nTPM
  • hippocampal formation: 174 nTPM

ReferencesPubMed · IEDB

Publications for MAPK3 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

1 publication

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. 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)
0.61
gnomAD pLI
0.04
gnomAD missense Z
1.74
DepMap mean gene effect
-0.13
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 MAPK3 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 MAPK3 as an antibody target. Whether an autoantibody or antibody against MAPK3 could matter depends on whether native MAPK3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MAPK3 is annotated at the cell surface, where native MAPK3 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label MAPK3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MAPK3. 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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