Seroatlas · Human Serome Atlas

MPP3

MAGUK p55 subfamily member 3

Also known as: DLG3, MPP3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q13368
Gene
MPP3
Ensembl
ENSG00000161647
Chromosome
17
Canonical length
585 aa
Protein class
Predicted intracellular proteins
Subcellular location
Nucleoplasm,Cytosol

OverviewNCBI Gene

This gene product is a member of a family of membrane-associated proteins termed MAGUKs (membrane-associated guanylate kinase homologs). MAGUKs interact with the cytoskeleton and regulate cell proliferation, signaling pathways, and intracellular junctions. This protein contains a conserved sequence, called the SH3 (src homology 3) motif, found in several other proteins that associate with the cytoskeleton and are suspected to play important roles in signal transduction. Alternatively spliced transcript variants have been identified. One transcript variant is experimentally supported, but it doesn't encode a protein. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

585 residues, UniProt reviewed canonical sequence.

>Q13368|MPP3
     1  MPVLSEDSGL HETLALLTSQ LRPDSNHKEE MGFLRDVFSE KSLSYLMKIH EKLRYYERQS
    61  PTPVLHSAVA LAEDVMEELQ AASVHSDERE LLQLLSTPHL RAVLMVHDTV AQKNFDPVLP
   121  PLPDNIDEDF DEESVKIVRL VKNKEPLGAT IRRDEHSGAV VVARIMRGGA ADRSGLVHVG
   181  DELREVNGIA VLHKRPDEIS QILAQSQGSI TLKIIPATQE EDRLKESKVF MRALFHYNPR
   241  EDRAIPCQEA GLPFQRRQVL EVVSQDDPTW WQAKRVGDTN LRAGLIPSKG FQERRLSYRR
   301  AAGTLPSPQS LRKPPYDQPC DKETCDCEGY LKGHYVAGLR RSFRLGCRER LGGSQEGKMS
   361  SGAESPELLT YEEVARYQHQ PGERPRLVVL IGSLGARLHE LKQKVVAENP QHFGVAVPHT
   421  TRPRKSHEKE GVEYHFVSKQ AFEADLHHNK FLEHGEYKEN LYGTSLEAIQ AVMAKNKVCL
   481  VDVEPEALKQ LRTSEFKPYI IFVKPAIQEK RKTPPMSPAC EDTAAPFDEQ QQEMAASAAF
   541  IDRHYGHLVD AVLVKEDLQG AYSQLKVVLE KLSKDTHWVP VSWVR

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MPP3 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)
0.36
Highest tissue expression
28 nTPM

Expression across tissuesHPA

Tissue

  • cerebellum: 28 nTPM
  • heart muscle: 15 nTPM
  • choroid plexus: 3.4 nTPM
  • pancreas: 3.2 nTPM
  • hypothalamus: 3.1 nTPM
  • lung: 2.7 nTPM

Single-cell type

  • cardiomyocytes: 358 nCPM
  • late spermatids: 101 nCPM
  • alveolar cells type 1: 99 nCPM
  • choroid plexus epithelial cells: 78 nCPM
  • early spermatids: 48 nCPM
  • podocytes: 37 nCPM

Immune cell

  • basophil: 0 nTPM
  • classical monocyte: 0 nTPM
  • eosinophil: 0 nTPM
  • gdT-cell: 0 nTPM
  • intermediate monocyte: 0 nTPM
  • MAIT T-cell: 0 nTPM

Brain region

  • cerebellum: 20 nTPM
  • medulla oblongata: 9 nTPM
  • pons: 7.9 nTPM
  • hypothalamus: 5.9 nTPM
  • choroid plexus: 4.8 nTPM
  • amygdala: 3.8 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)
0.63
gnomAD pLI
0
gnomAD missense Z
1.72
DepMap mean gene effect
-0.23
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

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of MPP3 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 MPP3 as an antibody target. Whether an autoantibody or antibody against MPP3 could matter depends on whether native MPP3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

MPP3 is annotated at the cell surface, where native MPP3 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 MPP3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/MPP3. 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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