Seroatlas · Human Serome Atlas

FMO5

Flavin-containing monooxygenase 5

Also known as: FMO5_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
P49326
Gene
FMO5
Ensembl
ENSG00000131781
Chromosome
1
Canonical length
533 aa
Protein class
Cancer-related genes, Enzymes, Metabolic proteins, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Endoplasmic reticulum,Cytosol

OverviewNCBI Gene

Metabolic N-oxidation of the diet-derived amino-trimethylamine (TMA) is mediated by flavin-containing monooxygenase and is subject to an inherited FMO3 polymorphism in man resulting in a small subpopulation with reduced TMA N-oxidation capacity resulting in fish odor syndrome Trimethylaminuria. Three forms of the enzyme, FMO1 found in fetal liver, FMO2 found in adult liver, and FMO3 are encoded by genes clustered in the 1q23-q25 region. Flavin-containing monooxygenases are NADPH-dependent flavoenzymes that catalyzes the oxidation of soft nucleophilic heteroatom centers in drugs, pesticides, and xenobiotics. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2009]

Canonical amino-acid sequenceUniProt

533 residues, UniProt reviewed canonical sequence.

>P49326|FMO5
     1  MTKKRIAVIG GGVSGLSSIK CCVEEGLEPV CFERTDDIGG LWRFQENPEE GRASIYKSVI
    61  INTSKEMMCF SDYPIPDHYP NFMHNAQVLE YFRMYAKEFD LLKYIRFKTT VCSVKKQPDF
   121  ATSGQWEVVT ESEGKKEMNV FDGVMVCTGH HTNAHLPLES FPGIEKFKGQ YFHSRDYKNP
   181  EGFTGKRVII IGIGNSGGDL AVEISQTAKQ VFLSTRRGAW ILNRVGDYGY PADVLFSSRL
   241  THFIWKICGQ SLANKYLEKK INQRFDHEMF GLKPKHRALS QHPTLNDDLP NRIISGLVKV
   301  KGNVKEFTET AAIFEDGSRE DDIDAVIFAT GYSFDFPFLE DSVKVVKNKI SLYKKVFPPN
   361  LERPTLAIIG LIQPLGAIMP ISELQGRWAT QVFKGLKTLP SQSEMMAEIS KAQEEIDKRY
   421  VESQRHTIQG DYIDTMEELA DLVGVRPNLL SLAFTDPKLA LHLLLGPCTP IHYRVQGPGK
   481  WDGARKAILT TDDRIRKPLM TRVVERSSSM TSTMTIGKFM LALAFFAIII AYF

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FMO5 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)
0.23
Highest tissue expression
639 nTPM

Expression across tissuesHPA

Tissue

  • liver: 639 nTPM
  • stomach: 117 nTPM
  • small intestine: 70 nTPM
  • duodenum: 67 nTPM
  • parathyroid gland: 64 nTPM
  • kidney: 48 nTPM

Single-cell type

  • hepatocytes: 434 nCPM
  • cardiomyocytes: 238 nCPM
  • alveolar cells type 2: 234 nCPM
  • cholangiocytes: 221 nCPM
  • gastric chief cells: 214 nCPM
  • enterocytes: 163 nCPM

Immune cell

  • classical monocyte: 13 nTPM
  • naive B-cell: 8.6 nTPM
  • basophil: 7.1 nTPM
  • intermediate monocyte: 5.9 nTPM
  • myeloid DC: 5.4 nTPM
  • memory B-cell: 4.8 nTPM

Brain region

  • white matter: 15 nTPM
  • pons: 13 nTPM
  • medulla oblongata: 13 nTPM
  • cerebellum: 11 nTPM
  • spinal cord: 10 nTPM
  • thalamus: 9.8 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)
1.45
gnomAD pLI
0
gnomAD missense Z
-0.63
DepMap mean gene effect
0.02
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 5% 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 FMO5 as an antibody target. Whether an autoantibody or antibody against FMO5 could matter depends on whether native FMO5 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FMO5 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 FMO5 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FMO5. 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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