Seroatlas · Human Serome Atlas

S100A4

Protein S100-A4

Also known as: 18A2, 42A, CAPL, FSP1, MTS1, P9KA, PEL98, S10A4_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P26447
Gene
S100A4
Ensembl
ENSG00000196154
Chromosome
1
Canonical length
101 aa
Protein class
Cancer-related genes, Plasma proteins, Predicted intracellular proteins, Predicted secreted proteins
Subcellular location
Nucleoplasm,Cytosol
Secretome location
Secreted to blood
Quaternary structure
Homodimer

OverviewNCBI Gene

The protein encoded by this gene is a member of the S100 family of proteins containing 2 EF-hand calcium-binding motifs. S100 proteins are localized in the cytoplasm and/or nucleus of a wide range of cells, and involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. S100 genes include at least 13 members which are located as a cluster on chromosome 1q21. This protein may function in motility, invasion, and tubulin polymerization. Chromosomal rearrangements and altered expression of this gene have been implicated in tumor metastasis. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

101 residues, UniProt reviewed canonical sequence.

>P26447|S100A4
     1  MACPLEKALD VMVSTFHKYS GKEGDKFKLN KSELKELLTR ELPSFLGKRT DEAAFQKLMS
    61  NLDSNRDNEV DFQEYCVFLS CIAMMCNEFF EGFPDKQPRK K

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against S100A4 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.4
Highest tissue expression
2,004 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 2,004 nTPM
  • adipose tissue: 1,199 nTPM
  • bone marrow: 1,028 nTPM
  • lung: 856 nTPM
  • breast: 680 nTPM
  • cervix: 610 nTPM

Single-cell type

  • ocular epithelial cells: 8,610 nCPM
  • neutrophils: 4,487 nCPM
  • monocytes: 3,839 nCPM
  • megakaryocytes: 2,875 nCPM
  • decidual stromal cells: 2,842 nCPM
  • cdc: 2,552 nCPM

Immune cell

  • total PBMC: 24,123 nTPM
  • classical monocyte: 13,587 nTPM
  • neutrophil: 12,218 nTPM
  • non-classical monocyte: 11,930 nTPM
  • myeloid DC: 9,294 nTPM
  • intermediate monocyte: 9,128 nTPM

Brain region

  • thalamus: 23 nTPM
  • white matter: 23 nTPM
  • medulla oblongata: 18 nTPM
  • choroid plexus: 18 nTPM
  • cerebral cortex: 17 nTPM
  • pons: 13 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)
1.86
gnomAD pLI
0.01
gnomAD missense Z
0.36
DepMap mean gene effect
0.06
DepMap dependency class
none

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 S100A4 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 S100A4 as an antibody target. Whether an autoantibody or antibody against S100A4 could matter depends on whether native S100A4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

S100A4 is annotated as secreted, so native S100A4 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label S100A4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/S100A4. 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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