Seroatlas · Human Serome Atlas

SMIM3

Small integral membrane protein 3

Also known as: C5orf62, MSTP150, NID67, SMIM3_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q9BZL3
Gene
SMIM3
Ensembl
ENSG00000256235
Chromosome
5
Canonical length
60 aa
Protein class
Predicted membrane proteins
Subcellular location
Vesicles

OverviewNCBI Gene

Enables identical protein binding activity. Predicted to be located in membrane. [provided by Alliance of Genome Resources, Jul 2025]

Canonical amino-acid sequenceUniProt

60 residues, UniProt reviewed canonical sequence.

>Q9BZL3|SMIM3
     1  MDAVSQVPME VVLPKHILDI WVIVLIILAT IVIMTSLLLC PATAVIIYRM RTHPILSGAV

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against SMIM3 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
Unknown
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.57
Highest tissue expression
151 nTPM

Expression across tissuesHPA

Tissue

  • adipose tissue: 151 nTPM
  • breast: 114 nTPM
  • choroid plexus: 113 nTPM
  • bone marrow: 84 nTPM
  • blood vessel: 64 nTPM
  • kidney: 59 nTPM

Single-cell type

  • platelets: 915 nCPM
  • mast cells: 134 nCPM
  • pericytes: 119 nCPM
  • megakaryocytes: 118 nCPM
  • adipocytes: 97 nCPM
  • pdcs: 97 nCPM

Immune cell

  • eosinophil: 73 nTPM
  • basophil: 69 nTPM
  • plasmacytoid DC: 57 nTPM
  • neutrophil: 43 nTPM
  • classical monocyte: 41 nTPM
  • total PBMC: 38 nTPM

Brain region

  • choroid plexus: 57 nTPM
  • thalamus: 19 nTPM
  • pons: 18 nTPM
  • medulla oblongata: 17 nTPM
  • hypothalamus: 16 nTPM
  • midbrain: 14 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)
1.97
gnomAD pLI
0
gnomAD missense Z
-0.8
DepMap mean gene effect
-0.3
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% 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

  • Small integral membrane protein 3
  • Small integral membrane protein 3

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads SMIM3 as an antibody target. Whether an autoantibody or antibody against SMIM3 could matter depends on whether native SMIM3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

SMIM3 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 SMIM3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/SMIM3. 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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