Seroatlas · Human Serome Atlas

FZD9

Frizzled-9

Also known as: CD349, FZD3, FZD9_HUMAN

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

Protein identityUniProt · HPA

UniProt accession
O00144
Gene
FZD9
Ensembl
ENSG00000188763
Chromosome
7
Canonical length
591 aa
Protein class
CD markers, G-protein coupled receptors, Human disease related genes, Predicted membrane proteins

OverviewNCBI Gene

Members of the 'frizzled' gene family encode 7-transmembrane domain proteins that are receptors for Wnt signaling proteins. The FZD9 gene is located within the Williams syndrome common deletion region of chromosome 7, and heterozygous deletion of the FZD9 gene may contribute to the Williams syndrome phenotype. FZD9 is expressed predominantly in brain, testis, eye, skeletal muscle, and kidney. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

591 residues, UniProt reviewed canonical sequence.

>O00144|FZD9
     1  MAVAPLRGAL LLWQLLAAGG AALEIGRFDP ERGRGAAPCQ AVEIPMCRGI GYNLTRMPNL
    61  LGHTSQGEAA AELAEFAPLV QYGCHSHLRF FLCSLYAPMC TDQVSTPIPA CRPMCEQARL
   121  RCAPIMEQFN FGWPDSLDCA RLPTRNDPHA LCMEAPENAT AGPAEPHKGL GMLPVAPRPA
   181  RPPGDLGPGA GGSGTCENPE KFQYVEKSRS CAPRCGPGVE VFWSRRDKDF ALVWMAVWSA
   241  LCFFSTAFTV LTFLLEPHRF QYPERPIIFL SMCYNVYSLA FLIRAVAGAQ SVACDQEAGA
   301  LYVIQEGLEN TGCTLVFLLL YYFGMASSLW WVVLTLTWFL AAGKKWGHEA IEAHGSYFHM
   361  AAWGLPALKT IVILTLRKVA GDELTGLCYV ASTDAAALTG FVLVPLSGYL VLGSSFLLTG
   421  FVALFHIRKI MKTGGTNTEK LEKLMVKIGV FSILYTVPAT CVIVCYVYER LNMDFWRLRA
   481  TEQPCAAAAG PGGRRDCSLP GGSVPTVAVF MLKIFMSLVV GITSGVWVWS SKTFQTWQSL
   541  CYRKIAAGRA RAKACRAPGS YGRGTHCHYK APTVVLHMTK TDPSLENPTH L

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FZD9 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
Cell surface
Secreted
No
Transmembrane segments
7
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
6.8 nTPM

Expression across tissuesHPA

Tissue

  • skeletal muscle: 6.8 nTPM
  • amygdala: 5.3 nTPM
  • cerebral cortex: 4.6 nTPM
  • hypothalamus: 4.6 nTPM
  • testis: 4.4 nTPM
  • midbrain: 4 nTPM

Single-cell type

  • late spermatids: 21 nCPM
  • paneth cells: 19 nCPM
  • oligodendrocyte progenitor cells: 18 nCPM
  • early spermatids: 9.6 nCPM
  • lymphatic endothelial cells: 6.1 nCPM
  • müller glia: 5 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

  • thalamus: 9 nTPM
  • medulla oblongata: 8.9 nTPM
  • amygdala: 7.3 nTPM
  • midbrain: 7.2 nTPM
  • pons: 6.7 nTPM
  • hypothalamus: 5.5 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)
0.83
gnomAD pLI
0
gnomAD missense Z
2.01
DepMap mean gene effect
-0.06
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

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FZD9 as an antibody target. Whether an autoantibody or antibody against FZD9 could matter depends on whether native FZD9 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FZD9 is annotated at the cell surface, where native FZD9 is exposed to circulating antibodies and is a prime autoantibody target that could block, deplete, or overstimulate it.

Annotation status

The present source text does not explicitly label FZD9 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FZD9. 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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