Seroatlas · Human Serome Atlas

TMEM123

Porimin

Also known as: KCT3, PORIM_HUMAN, PORIMIN

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

Protein identityUniProt · HPA

UniProt accession
Q8N131
Gene
TMEM123
Ensembl
ENSG00000152558
Chromosome
11
Canonical length
208 aa
Protein class
Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Golgi apparatus,Vesicles,Cytosol

OverviewNCBI Gene

This gene encodes a highly glycosylated transmembrane protein with a high content of threonine and serine residues in its extracellular domain, similar to a broadly defined category of proteins termed mucins. Exposure of some cell types to anti-PORIMIN (pro-oncosis receptor inducing membrane injury) antibody, crosslinks this protein on the cell surface and induces a type of cell death termed oncosis. Oncosis is distinct from apoptosis and is characterized by a loss of cell membrane integrity without DNA fragmentation. This gene product is proposed to function as a cell surface receptor that mediates cell death. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

208 residues, UniProt reviewed canonical sequence.

>Q8N131|TMEM123
     1  MGLGARGAWA ALLLGTLQVL ALLGAAHESA AMAASANIEN SGLPHNSSAN STETLQHVPS
    61  DHTNETSNST VKPPTSVASD SSNTTVTTMK PTAASNTTTP GMVSTNMTST TLKSTPKTTS
   121  VSQNTSQIST STMTVTHNSS VTSAASSVTI TTTMHSEAKK GSKFDTGSFV GGIVLTLGVL
   181  SILYIGCKMY YSRRGIRYRT IDEHDAII

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TMEM123 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
1
Mean surface accessibility (rSASA)
0.66
Highest tissue expression
368 nTPM

Expression across tissuesHPA

Tissue

  • liver: 368 nTPM
  • thyroid gland: 292 nTPM
  • thymus: 222 nTPM
  • bone marrow: 213 nTPM
  • salivary gland: 211 nTPM
  • lymph node: 183 nTPM

Single-cell type

  • kupffer cells: 489 nCPM
  • lacrimal acinar cells: 447 nCPM
  • neutrophil progenitors: 421 nCPM
  • monocytes: 408 nCPM
  • salivary acinar cells: 358 nCPM
  • epididymal efferent duct ciliated cells: 340 nCPM

Immune cell

  • total PBMC: 249 nTPM
  • NK-cell: 225 nTPM
  • naive CD4 T-cell: 209 nTPM
  • eosinophil: 208 nTPM
  • T-reg: 184 nTPM
  • naive CD8 T-cell: 182 nTPM

Brain region

  • white matter: 163 nTPM
  • medulla oblongata: 131 nTPM
  • midbrain: 126 nTPM
  • choroid plexus: 121 nTPM
  • spinal cord: 110 nTPM
  • hypothalamus: 108 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)
0.62
gnomAD pLI
0.65
gnomAD missense Z
-0.51
DepMap mean gene effect
0.09
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 6% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads TMEM123 as an antibody target. Whether an autoantibody or antibody against TMEM123 could matter depends on whether native TMEM123 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

TMEM123 is annotated at the cell surface, where native TMEM123 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • Exposure of some cell types to anti-PORIMIN (pro-oncosis receptor inducing membrane injury) antibody, crosslinks this protein on the cell surface and induces a type of cell death termed oncosis.

Canonical record: https://seroatlas.com/gene/TMEM123. 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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