Seroatlas · Human Serome Atlas

MDM4

Protein Mdm4

Also known as: HDMX, MDM4_HUMAN, MDMX

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

Protein identityUniProt · HPA

UniProt accession
O15151
Gene
MDM4
Ensembl
ENSG00000198625
Chromosome
1
Canonical length
490 aa
Protein class
Cancer-related genes, Disease related genes, Human disease related genes, Predicted intracellular proteins
Subcellular location
Nucleoplasm

OverviewNCBI Gene

This gene encodes a nuclear protein that contains a p53 binding domain at the N-terminus and a RING finger domain at the C-terminus, and shows structural similarity to p53-binding protein MDM2. Both proteins bind the p53 tumor suppressor protein and inhibit its activity, and have been shown to be overexpressed in a variety of human cancers. However, unlike MDM2 which degrades p53, this protein inhibits p53 by binding its transcriptional activation domain. This protein also interacts with MDM2 protein via the RING finger domain, and inhibits the latter's degradation. So this protein can reverse MDM2-targeted degradation of p53, while maintaining suppression of p53 transactivation and apoptotic functions. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene. [provided by RefSeq, Feb 2011]

Canonical amino-acid sequenceUniProt

490 residues, UniProt reviewed canonical sequence.

>O15151|MDM4
     1  MTSFSTSAQC STSDSACRIS PGQINQVRPK LPLLKILHAA GAQGEMFTVK EVMHYLGQYI
    61  MVKQLYDQQE QHMVYCGGDL LGELLGRQSF SVKDPSPLYD MLRKNLVTLA TATTDAAQTL
   121  ALAQDHSMDI PSQDQLKQSA EESSTSRKRT TEDDIPTLPT SEHKCIHSRE DEDLIENLAQ
   181  DETSRLDLGF EEWDVAGLPW WFLGNLRSNY TPRSNGSTDL QTNQDVGTAI VSDTTDDLWF
   241  LNESVSEQLG VGIKVEAADT EQTSEEVGKV SDKKVIEVGK NDDLEDSKSL SDDTDVEVTS
   301  EDEWQCTECK KFNSPSKRYC FRCWALRKDW YSDCSKLTHS LSTSDITAIP EKENEGNDVP
   361  DCRRTISAPV VRPKDAYIKK ENSKLFDPCN SVEFLDLAHS SESQETISSM GEQLDNLSEQ
   421  RTDTENMEDC QNLLKPCSLC EKRPRDGNII HGRTGHLVTC FHCARRLKKA GASCPICKKE
   481  IQLVIKVFIA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MDM4 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)
0.55
Highest tissue expression
51 nTPM

Expression across tissuesHPA

Tissue

  • bone marrow: 51 nTPM
  • thymus: 28 nTPM
  • retina: 23 nTPM
  • spleen: 21 nTPM
  • skin: 19 nTPM
  • testis: 19 nTPM

Single-cell type

  • neutrophils: 353 nCPM
  • choroid plexus epithelial cells: 283 nCPM
  • late spermatids: 255 nCPM
  • sertoli cells: 252 nCPM
  • b-cells: 247 nCPM
  • microglia: 243 nCPM

Immune cell

  • basophil: 4.1 nTPM
  • eosinophil: 3.6 nTPM
  • neutrophil: 3.6 nTPM
  • naive B-cell: 3.3 nTPM
  • plasmacytoid DC: 3.1 nTPM
  • memory B-cell: 2.8 nTPM

Brain region

  • choroid plexus: 106 nTPM
  • white matter: 102 nTPM
  • thalamus: 69 nTPM
  • basal ganglia: 69 nTPM
  • medulla oblongata: 69 nTPM
  • hypothalamus: 68 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MDM4.

Disease | AllUniProt

Conditions MDM4 is implicated in, by any mechanism.

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)
0.11
gnomAD pLI
1
gnomAD missense Z
1.71
DepMap mean gene effect
-0.18
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 9% 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 MDM4 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 MDM4 as an antibody target. Whether an autoantibody or antibody against MDM4 could matter depends on whether native MDM4 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MDM4 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 MDM4 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MDM4. 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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