Seroatlas · Human Serome Atlas

AP4M1

AP-4 complex subunit mu-1

Also known as: AP4M1_HUMAN, MU-4, MU-ARP2, SPG50

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

Protein identityUniProt · HPA

UniProt accession
O00189
Gene
AP4M1
Ensembl
ENSG00000221838
Chromosome
7
Canonical length
453 aa
Protein class
Disease related genes, Human disease related genes, Potential drug targets, Predicted intracellular proteins, Transporters

OverviewNCBI Gene

This gene encodes a subunit of the heterotetrameric AP-4 complex. The encoded protein belongs to the adaptor complexes medium subunits family. This AP-4 complex is involved in the recognition and sorting of cargo proteins with tyrosine-based motifs from the trans-golgi network to the endosomal-lysosomal system. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

453 residues, UniProt reviewed canonical sequence.

>O00189|AP4M1
     1  MISQFFILSS KGDPLIYKDF RGDSGGRDVA ELFYRKLTGL PGDESPVVMH HHGRHFIHIR
    61  HSGLYLVVTT SENVSPFSLL ELLSRLATLL GDYCGSLGEG TISRNVALVY ELLDEVLDYG
   121  YVQTTSTEML RNFIQTEAVV SKPFSLFDLS SVGLFGAETQ QSKVAPSSAA SRPVLSSRSD
   181  QSQKNEVFLD VVERLSVLIA SNGSLLKVDV QGEIRLKSFL PSGSEMRIGL TEEFCVGKSE
   241  LRGYGPGIRV DEVSFHSSVN LDEFESHRIL RLQPPQGELT VMRYQLSDDL PSPLPFRLFP
   301  SVQWDRGSGR LQVYLKLRCD LLSKSQALNV RLHLPLPRGV VSLSQELSSP EQKAELAEGA
   361  LRWDLPRVQG GSQLSGLFQM DVPGPPGPPS HGLSTSASPL GLGPASLSFE LPRHTCSGLQ
   421  VRFLRLAFRP CGNANPHKWV RHLSHSDAYV IRI

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against AP4M1 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
Other membrane
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.3
Highest tissue expression
31 nTPM

Expression across tissuesHPA

Tissue

  • testis: 31 nTPM
  • pituitary gland: 15 nTPM
  • colon: 14 nTPM
  • endometrium: 14 nTPM
  • pancreas: 13 nTPM
  • stomach: 13 nTPM

Single-cell type

  • late spermatids: 135 nCPM
  • late primary spermatocytes: 82 nCPM
  • early primary spermatocytes: 79 nCPM
  • early spermatids: 60 nCPM
  • differentiating spermatogonia: 52 nCPM
  • respiratory ciliated cells: 47 nCPM

Immune cell

  • non-classical monocyte: 11 nTPM
  • eosinophil: 9.4 nTPM
  • myeloid DC: 8.7 nTPM
  • intermediate monocyte: 8 nTPM
  • classical monocyte: 6.5 nTPM
  • memory B-cell: 5.4 nTPM

Brain region

  • medulla oblongata: 11 nTPM
  • thalamus: 10 nTPM
  • pons: 10 nTPM
  • cerebral cortex: 9.9 nTPM
  • midbrain: 9.8 nTPM
  • spinal cord: 8.9 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about AP4M1.

Disease | AllUniProt

Conditions AP4M1 is implicated in, by any mechanism.

  • Spastic paraplegia 50, autosomal recessive (SPG50) MIM:612936

Disease | GeneticClinVar

67 pathogenic / likely-pathogenic of 496 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)
1.31
gnomAD pLI
0
gnomAD missense Z
-1.21
DepMap mean gene effect
0.06
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 AP4M1 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 AP4M1 as an antibody target. Whether an autoantibody or antibody against AP4M1 could matter depends on whether native AP4M1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

AP4M1 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 AP4M1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/AP4M1. 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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