Seroatlas · Human Serome Atlas

FCRLB

Fc receptor-like B

Also known as: FCRL2, FCRLB_HUMAN, FCRLM2, FCRLY, FLJ31052, FREB-2

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

Protein identityUniProt · HPA

UniProt accession
Q6BAA4
Gene
FCRLB
Ensembl
ENSG00000162746
Chromosome
1
Canonical length
426 aa
Protein class
Predicted intracellular proteins
Subcellular location
Cytosol
Secretome location
Intracellular and membrane

OverviewNCBI Gene

FCRL2 belongs to the Fc receptor family. Fc receptors are involved in phagocytosis, antibody-dependent cell cytotoxicity, immediate hypersensitivity, and transcytosis of immunoglobulins via their ability to bind immunoglobulin (Ig) constant regions (Chikaev et al., 2005 [PubMed 15676285]).[supplied by OMIM, Mar 2008]

Canonical amino-acid sequenceUniProt

426 residues, UniProt reviewed canonical sequence.

>Q6BAA4|FCRLB
     1  MWPLTALLLL VPSSGQAATL EKPILSLHPP WTTIFKGERV TLKCDGYHPL LLELQPISTL
    61  WYLGHLLLPS HKKSIEVQTP GVYRCQTRGA PVSDPIHLSV SNDWLILQVP YAPVFEGEPL
   121  VLRCRGWYDK VVYKLHYYHD GQAVRYFHSS ANYTVLQARA SDSGRYQCSG TMRIPVESAP
   181  MFSAKVAVTV QELFRAPVLR VMGPREARGA ALGGVVLRCD TRLHPQKRDT PLQFAFYKYS
   241  RAVRRFDWGA EYTVPEPEVE ELESYWCEAA TATRSVRKRS PWLQLPGPGS PLDPASTTAP
   301  APWAAALAPG NRPLSFRKPP VSRSVPLVTS VRNTTSTGLQ FPASGAPTAG PPACAPPTPL
   361  EQSAGALKPD VDLLLREMQL LKGLLSRVVL ELKEPQALRE LRGTPETPTS HFAVSPGTPE
   421  TTPVES

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FCRLB 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
0
Mean surface accessibility (rSASA)
0.45
Highest tissue expression
1.6 nTPM

Expression across tissuesHPA

Tissue

  • tonsil: 1.6 nTPM
  • kidney: 0.8 nTPM
  • lymph node: 0.8 nTPM
  • seminal vesicle: 0.8 nTPM
  • appendix: 0.6 nTPM
  • cerebral cortex: 0.3 nTPM

Single-cell type

  • thymic myoid cells: 11 nCPM
  • urothelial cells: 8.2 nCPM
  • extravillous trophoblasts: 7.3 nCPM
  • granulosa cells: 7.3 nCPM
  • hepatic stellate cells: 6.5 nCPM
  • fallopian secretory cells: 6 nCPM

Immune cell

  • basophil: 4 nTPM
  • NK-cell: 3.6 nTPM
  • memory B-cell: 3.3 nTPM
  • naive B-cell: 2.9 nTPM
  • eosinophil: 1.8 nTPM
  • gdT-cell: 1.8 nTPM

Brain region

  • cerebral cortex: 0.9 nTPM
  • white matter: 0.9 nTPM
  • pons: 0.8 nTPM
  • hippocampal formation: 0.7 nTPM
  • medulla oblongata: 0.7 nTPM
  • basal ganglia: 0.6 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)
1.5
gnomAD pLI
0
gnomAD missense Z
0.52
DepMap mean gene effect
0
DepMap dependency class
none

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

FCRLB 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.

Source-annotated serology context

The source annotations explicitly mention antibody, autoantibody, autoantigen, or autoimmune context. This is biological context, not study-specific reactivity.

  • Fc receptors are involved in phagocytosis, antibody-dependent cell cytotoxicity, immediate hypersensitivity, and transcytosis of immunoglobulins via their ability to bind immunoglobulin (Ig) constant regions (Chikaev et al., 2005 [PubMed 15676285]).[supplied by OMIM, Mar 2008]

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