Seroatlas · Human Serome Atlas

FJX1

Four-jointed box protein 1

Also known as: FJX1_HUMAN, FLJ22416, FLJ25593

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

Protein identityUniProt · HPA

UniProt accession
Q86VR8
Gene
FJX1
Ensembl
ENSG00000179431
Chromosome
11
Canonical length
437 aa
Protein class
Predicted intracellular proteins
Subcellular location
Vesicles
Secretome location
Intracellular and membrane

OverviewNCBI Gene

The protein encoded by this gene is the human ortholog of mouse and Drosophila four-jointed gene product. The Drosophila protein is important for growth and differentiation of legs and wings, and for proper development of the eyes. The exact function of this gene in humans is not known. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

437 residues, UniProt reviewed canonical sequence.

>Q86VR8|FJX1
     1  MGRRMRGAAA TAGLWLLALG SLLALWGGLL PPRTELPASR PPEDRLPRRP ARSGGPAPAP
    61  RFPLPPPLAW DARGGSLKTF RALLTLAAGA DGPPRQSRSE PRWHVSARQP RPEESAAVHG
   121  GVFWSRGLEE QVPPGFSEAQ AAAWLEAARG ARMVALERGG CGRSSNRLAR FADGTRACVR
   181  YGINPEQIQG EALSYYLARL LGLQRHVPPL ALARVEARGA QWAQVQEELR AAHWTEGSVV
   241  SLTRWLPNLT DVVVPAPWRS EDGRLRPLRD AGGELANLSQ AELVDLVQWT DLILFDYLTA
   301  NFDRLVSNLF SLQWDPRVMQ RATSNLHRGP GGALVFLDNE AGLVHGYRVA GMWDKYNEPL
   361  LQSVCVFRER TARRVLELHR GQDAAARLLR LYRRHEPRFP ELAALADPHA QLLQRRLDFL
   421  AKHILHCKAK YGRRSGT

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FJX1 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
Secreted
Secreted
Yes
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.35
Highest tissue expression
13 nTPM

Expression across tissuesHPA

Tissue

  • basal ganglia: 13 nTPM
  • cerebral cortex: 13 nTPM
  • amygdala: 8.8 nTPM
  • hippocampal formation: 8.7 nTPM
  • ovary: 8.7 nTPM
  • adipose tissue: 8.5 nTPM

Single-cell type

  • bergmann glia: 39 nCPM
  • epididymal basal cells: 38 nCPM
  • cytotrophoblasts: 34 nCPM
  • endometrial ciliated cells: 32 nCPM
  • breast myoepithelial cells: 32 nCPM
  • basal keratinocytes: 25 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

  • midbrain: 27 nTPM
  • thalamus: 24 nTPM
  • cerebral cortex: 20 nTPM
  • hippocampal formation: 20 nTPM
  • basal ganglia: 20 nTPM
  • white matter: 20 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about FJX1.

Disease | ImmuneIEDB

Conditions an epitope on FJX1 was assayed in.

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)
0.33
gnomAD pLI
0.94
gnomAD missense Z
0.66
DepMap mean gene effect
-0.08
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

Cellular components

Protein domainsUniProt · Pfam · InterPro

  • Four-jointed box protein 1/four-jointed protein

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FJX1 as an antibody target. Whether an autoantibody or antibody against FJX1 could matter depends on whether native FJX1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FJX1 is annotated as secreted, so native FJX1 circulates and is directly accessible to antibodies. Secreted and cell-surface proteins are the autoantibody targets most likely to act like drugs, blocking or depleting the native protein.

Annotation status

The present source text does not explicitly label FJX1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FJX1. 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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