Seroatlas · Human Serome Atlas

FCGR1A

High affinity immunoglobulin gamma Fc receptor I

Also known as: CD64, CD64A, FCG1, FcgammaRI, FcgammaRIa, FCGR1, FCGR1_HUMAN

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

Protein identityUniProt · HPA

UniProt accession: P12314
Gene: FCGR1A
Ensembl: ENSG00000150337
Chromosome: 1
Canonical length: 374 aa
Protein class: CD markers, FDA approved drug targets, Predicted membrane proteins
Subcellular location: Golgi apparatus,Vesicles,Plasma membrane

OverviewNCBI Gene

This gene encodes a protein that plays an important role in the immune response. This protein is a high-affinity Fc-gamma receptor. The gene is one of three related gene family members located on chromosome 1. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

374 residues, UniProt reviewed canonical sequence.

>P12314|FCGR1A
     1  MWFLTTLLLW VPVDGQVDTT KAVITLQPPW VSVFQEETVT LHCEVLHLPG SSSTQWFLNG
    61  TATQTSTPSY RITSASVNDS GEYRCQRGLS GRSDPIQLEI HRGWLLLQVS SRVFTEGEPL
   121  ALRCHAWKDK LVYNVLYYRN GKAFKFFHWN SNLTILKTNI SHNGTYHCSG MGKHRYTSAG
   181  ISVTVKELFP APVLNASVTS PLLEGNLVTL SCETKLLLQR PGLQLYFSFY MGSKTLRGRN
   241  TSSEYQILTA RREDSGLYWC EAATEDGNVL KRSPELELQV LGLQLPTPVW FHVLFYLAVG
   301  IMFLVNTVLW VTIRKELKRK KKWDLEISLD SGHEKKVISS LQEDRHLEEE LKCQEQKEEQ
   361  LQEGVHRKEP QGAT

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FCGR1A 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: 1
Mean surface accessibility (rSASA): 0.38
Highest tissue expression: 95 nTPM

Expression across tissuesHPA

Tissue

epididymis: 95 nTPM
appendix: 40 nTPM
placenta: 32 nTPM
lung: 28 nTPM
spinal cord: 26 nTPM
smooth muscle: 19 nTPM

Single-cell type

hofbauer cells: 350 nCPM
late spermatids: 88 nCPM
neutrophils: 81 nCPM
kupffer cells: 74 nCPM
monocytes: 61 nCPM
epididymal principal cells: 55 nCPM

Immune cell

classical monocyte: 137 nTPM
neutrophil: 99 nTPM
intermediate monocyte: 57 nTPM
total PBMC: 50 nTPM
myeloid DC: 37 nTPM
non-classical monocyte: 13 nTPM

Brain region

white matter: 28 nTPM
medulla oblongata: 19 nTPM
spinal cord: 18 nTPM
thalamus: 16 nTPM
pons: 12 nTPM
cerebral cortex: 11 nTPM

ReferencesPubMed · IEDB

Publications for FCGR1A from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Reference: AutoantibodyPubMed

6 publications

Splenic macrophages maintain the anti-platelet autoimmune response via uptake of opsonized platelets in patients with immune thrombocytopenic purpura.
2009 · J Thromb Haemost · RCR 2.7 · 108 citations
Suppressing anti-citrullinated protein antibody-induced osteoclastogenesis in rheumatoid arthritis using anti-CD64 and PAD-2 inhibitors.
2025 · Clin Exp Rheumatol · RCR 2.5 · 7 citations
Activation of human synovial mast cells from rheumatoid arthritis or osteoarthritis patients in response to aggregated IgG through Fcγ receptor I and Fcγ receptor II.
2013 · Arthritis Rheum · RCR 1.5 · 47 citations
Excessive exposure to anionic surfaces maintains autoantibody response to beta(2)-glycoprotein I in patients with antiphospholipid syndrome.
2007 · Blood · RCR 1.2 · 44 citations
Immunosuppressive monoclonal antibody to CD64 from patients with long-term stable multiple sclerosis.
2013 · J Neuroimmunol · RCR 0.1 · 4 citations

Show 1 more

Preclinical assessment of two FcγRI-specific antibodies that competitively inhibit immune complex-FcγRI binding to suppress autoimmune responses.
2025 · Nat Commun · 3 citations

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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): 1.08
gnomAD pLI: 0
gnomAD missense Z: 0.58
DepMap mean gene effect: -0.82
DepMap dependency class: common

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

IgG binding
IgG receptor activity
high-affinity IgG receptor activity

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of FCGR1A in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FCGR1A as an antibody target. Whether an autoantibody or antibody against FCGR1A could matter depends on whether native FCGR1A is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FCGR1A is annotated at the cell surface, where native FCGR1A 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 FCGR1A as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

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