Seroatlas · Human Serome Atlas

TM9SF2

Transmembrane 9 superfamily member 2

Also known as: P76, TM9S2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q99805
Gene
TM9SF2
Ensembl
ENSG00000125304
Chromosome
13
Canonical length
663 aa
Protein class
Predicted intracellular proteins, Predicted membrane proteins, Transporters

OverviewNCBI Gene

This gene encodes a member of the transmembrane 9 superfamily. The encoded 76 kDa protein localizes to early endosomes in human cells. The encoded protein possesses a conserved and highly hydrophobic C-terminal domain which contains nine transmembrane domains. The protein may play a role in small molecule transport or act as an ion channel. A pseudogene associated with this gene is located on the X chromosome. [provided by RefSeq, Oct 2012]

Canonical amino-acid sequenceUniProt

663 residues, UniProt reviewed canonical sequence.

>Q99805|TM9SF2
     1  MSARLPVLSP PRWPRLLLLS LLLLGAVPGP RRSGAFYLPG LAPVNFCDEE KKSDECKAEI
    61  ELFVNRLDSV ESVLPYEYTA FDFCQASEGK RPSENLGQVL FGERIEPSPY KFTFNKKETC
   121  KLVCTKTYHT EKAEDKQKLE FLKKSMLLNY QHHWIVDNMP VTWCYDVEDG QRFCNPGFPI
   181  GCYITDKGHA KDACVISSDF HERDTFYIFN HVDIKIYYHV VETGSMGARL VAAKLEPKSF
   241  KHTHIDKPDC SGPPMDISNK ASGEIKIAYT YSVSFEEDDK IRWASRWDYI LESMPHTHIQ
   301  WFSIMNSLVI VLFLSGMVAM IMLRTLHKDI ARYNQMDSTE DAQEEFGWKL VHGDIFRPPR
   361  KGMLLSVFLG SGTQILIMTF VTLFFACLGF LSPANRGALM TCAVVLWVLL GTPAGYVAAR
   421  FYKSFGGEKW KTNVLLTSFL CPGIVFADFF IMNLILWGEG SSAAIPFGTL VAILALWFCI
   481  SVPLTFIGAY FGFKKNAIEH PVRTNQIPRQ IPEQSFYTKP LPGIIMGGIL PFGCIFIQLF
   541  FILNSIWSHQ MYYMFGFLFL VFIILVITCS EATILLCYFH LCAEDYHWQW RSFLTSGFTA
   601  VYFLIYAVHY FFSKLQITGT ASTILYFGYT MIMVLIFFLF TGTIGFFACF WFVTKIYSVV
   661  KVD

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against TM9SF2 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
9
Mean surface accessibility (rSASA)
0.28
Highest tissue expression
158 nTPM

Expression across tissuesHPA

Tissue

  • liver: 158 nTPM
  • parathyroid gland: 119 nTPM
  • rectum: 116 nTPM
  • thyroid gland: 113 nTPM
  • duodenum: 112 nTPM
  • small intestine: 112 nTPM

Single-cell type

  • neutrophil progenitors: 353 nCPM
  • esophageal apical cells: 287 nCPM
  • neutrophils: 271 nCPM
  • syncytiotrophoblasts: 257 nCPM
  • gastric progenitor cells: 233 nCPM
  • prostatic hillock cells: 224 nCPM

Immune cell

  • neutrophil: 252 nTPM
  • basophil: 193 nTPM
  • non-classical monocyte: 183 nTPM
  • intermediate monocyte: 181 nTPM
  • total PBMC: 178 nTPM
  • eosinophil: 175 nTPM

Brain region

  • choroid plexus: 106 nTPM
  • white matter: 68 nTPM
  • hypothalamus: 58 nTPM
  • spinal cord: 57 nTPM
  • basal ganglia: 52 nTPM
  • thalamus: 51 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)
0.08
gnomAD pLI
1
gnomAD missense Z
3.27
DepMap mean gene effect
-0.13
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 7% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of TM9SF2 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 TM9SF2 as an antibody target. Whether an autoantibody or antibody against TM9SF2 could matter depends on whether native TM9SF2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

TM9SF2 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 TM9SF2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/TM9SF2. 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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