Seroatlas · Human Serome Atlas

FRMD3

FERM domain-containing protein 3

Also known as: EPB41L4O, FRMD3_HUMAN, MGC20553

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

Protein identityUniProt · HPA

UniProt accession
A2A2Y4
Gene
FRMD3
Ensembl
ENSG00000172159
Chromosome
9
Canonical length
597 aa
Protein class
Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Golgi apparatus,Plasma membrane

OverviewNCBI Gene

The protein encoded by this gene is a single pass membrane protein primarily found in ovaries. A similar protein in erythrocytes helps determine the shape of red blood cells, but the function of the encoded protein has not been determined. There is some evidence that this is a tumor suppressor gene, and there is also evidence linking defects in this gene to susceptibility to diabetic nephropathy in type 1 diabetes. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2011]

Canonical amino-acid sequenceUniProt

597 residues, UniProt reviewed canonical sequence.

>A2A2Y4|FRMD3
     1  MFASCHCVPR GRRTMKMIHF RSSSVKSLSQ EMRCTIRLLD DSEISCHIQR ETKGQFLIDH
    61  ICNYYSLLEK DYFGIRYVDP EKQRHWLEPN KSIFKQMKTH PPYTMCFRVK FYPHEPLKIK
   121  EELTRYLLYL QIKRDIFHGR LLCSFSDAAY LGACIVQAEL GDYDPDEHPE NYISEFEIFP
   181  KQSQKLERKI VEIHKNELRG QSPPVAEFNL LLKAHTLETY GVDPHPCKDS TGTTTFLGFT
   241  AAGFVVFQGN KRIHLIKWPD VCKLKFEGKT FYVIGTQKEK KAMLAFHTST PAACKHLWKC
   301  GVENQAFYKY AKSSQIKTVS SSKIFFKGSR FRYSGKVAKE VVEASSKIQR EPPEVHRANI
   361  TQSRSSHSLN KQLIINMEPL QPLLPSPSEQ EEELPLGEGV PLPKEENISA PLISSSPVKA
   421  AREYEDPPSE EEDKIKEEPL TISELVYNPS ASLLPTPVDD DEIDMLFDCP SRLELEREDT
   481  DSFEDLEADE NAFLIAEEEE LKEARRALSW SYDILTGHIR VNPLVKSFSR LLVVGLGLLL
   541  FVFPLLLLLL ESGIDLSFLC EIRQTPEFEQ FHYEYYCPLK EWVAGKVHLI LYMLGCS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FRMD3 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
Intracellular
Secreted
No
Transmembrane segments
1
Mean surface accessibility (rSASA)
0.38
Highest tissue expression
80 nTPM

Expression across tissuesHPA

Tissue

  • heart muscle: 80 nTPM
  • skeletal muscle: 76 nTPM
  • tongue: 70 nTPM
  • retina: 20 nTPM
  • parathyroid gland: 19 nTPM
  • epididymis: 15 nTPM

Single-cell type

  • retinal bipolar cells: 1,020 nCPM
  • podocytes: 1,019 nCPM
  • retinal horizontal cells: 851 nCPM
  • corticotrophs: 823 nCPM
  • distal convoluted tubule cells: 715 nCPM
  • pericytes: 585 nCPM

Immune cell

  • total PBMC: 5.9 nTPM
  • intermediate monocyte: 3.4 nTPM
  • neutrophil: 2.5 nTPM
  • classical monocyte: 2 nTPM
  • non-classical monocyte: 1.5 nTPM
  • MAIT T-cell: 0.4 nTPM

Brain region

  • choroid plexus: 22 nTPM
  • medulla oblongata: 19 nTPM
  • hypothalamus: 18 nTPM
  • midbrain: 15 nTPM
  • spinal cord: 13 nTPM
  • thalamus: 13 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)
0.44
gnomAD pLI
0.27
gnomAD missense Z
0.88
DepMap mean gene effect
0.11
DepMap dependency class
none

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

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FRMD3 as an antibody target. Whether an autoantibody or antibody against FRMD3 could matter depends on whether native FRMD3 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FRMD3 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 FRMD3 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FRMD3. 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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