Seroatlas · Human Serome Atlas

FMO2

Flavin-containing monooxygenase 2

Also known as: FMO2_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
Q99518
Gene
FMO2
Ensembl
ENSG00000094963
Chromosome
1
Canonical length
535 aa
Protein class
Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins

OverviewNCBI Gene

This gene encodes a flavin-containing monooxygenase family member. It is an NADPH-dependent enzyme that catalyzes the N-oxidation of some primary alkylamines through an N-hydroxylamine intermediate. However, some human populations contain an allele (FMO2*2A) with a premature stop codon, resulting in a protein that is C-terminally-truncated, has no catalytic activity, and is likely degraded rapidly. This gene is found in a cluster with other related family members on chromosome 1. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2014]

Canonical amino-acid sequenceUniProt

535 residues, UniProt reviewed canonical sequence.

>Q99518|FMO2
     1  MAKKVAVIGA GVSGLISLKC CVDEGLEPTC FERTEDIGGV WRFKENVEDG RASIYQSVVT
    61  NTSKEMSCFS DFPMPEDFPN FLHNSKLLEY FRIFAKKFDL LKYIQFQTTV LSVRKCPDFS
   121  SSGQWKVVTQ SNGKEQSAVF DAVMVCSGHH ILPHIPLKSF PGMERFKGQY FHSRQYKHPD
   181  GFEGKRILVI GMGNSGSDIA VELSKNAAQV FISTRHGTWV MSRISEDGYP WDSVFHTRFR
   241  SMLRNVLPRT AVKWMIEQQM NRWFNHENYG LEPQNKYIMK EPVLNDDVPS RLLCGAIKVK
   301  STVKELTETS AIFEDGTVEE NIDVIIFATG YSFSFPFLED SLVKVENNMV SLYKYIFPAH
   361  LDKSTLACIG LIQPLGSIFP TAELQARWVT RVFKGLCSLP SERTMMMDII KRNEKRIDLF
   421  GESQSQTLQT NYVDYLDELA LEIGAKPDFC SLLFKDPKLA VRLYFGPCNS YQYRLVGPGQ
   481  WEGARNAIFT QKQRILKPLK TRALKDSSNF SVSFLLKILG LLAVVVAFFC QLQWS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FMO2 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
1
Mean surface accessibility (rSASA)
0.24
Highest tissue expression
94 nTPM

Expression across tissuesHPA

Tissue

  • blood vessel: 94 nTPM
  • lung: 75 nTPM
  • adipose tissue: 65 nTPM
  • esophagus: 62 nTPM
  • heart muscle: 40 nTPM
  • breast: 36 nTPM

Single-cell type

  • esophageal apical cells: 1,176 nCPM
  • fibro-adipogenic progenitors: 220 nCPM
  • alveolar cells type 1: 210 nCPM
  • esophageal suprabasal cells: 179 nCPM
  • respiratory basal cells: 145 nCPM
  • breast myoepithelial cells: 134 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

  • hypothalamus: 9.5 nTPM
  • choroid plexus: 6.1 nTPM
  • basal ganglia: 5 nTPM
  • medulla oblongata: 4.7 nTPM
  • thalamus: 3.9 nTPM
  • pons: 3.7 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)
1.06
gnomAD pLI
0
gnomAD missense Z
0.1
DepMap mean gene effect
0.08
DepMap dependency class
none

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FMO2 as an antibody target. Whether an autoantibody or antibody against FMO2 could matter depends on whether native FMO2 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FMO2 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 FMO2 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FMO2. 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).

© 2026 · Seroatlas, Discover Oregon LLC · Terms of use

Loading the interactive Seroatlas protein explorer...