Seroatlas · Human Serome Atlas

CD209

CD209 antigen

Also known as: CD209_HUMAN, CDSIGN, CLEC4L, DC-SIGN, DC-SIGN1, hDC-SIGN

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

Protein identityUniProt · HPA

UniProt accession
Q9NNX6
Gene
CD209
Ensembl
ENSG00000090659
Chromosome
19
Canonical length
404 aa
Protein class
CD markers, Predicted intracellular proteins, Predicted membrane proteins
Secretome location
Intracellular and membrane
Quaternary structure
Homotetramer

OverviewNCBI Gene

This gene encodes a C-type lectin that functions in cell adhesion and pathogen recognition. This receptor recognizes a wide range of evolutionarily divergent pathogens with a large impact on public health, including leprosy and tuberculosis mycobacteria, the Ebola, hepatitis C, HIV-1 and Dengue viruses, and the SARS-CoV acute respiratory syndrome coronavirus. The protein is organized into four distinct domains: a C-terminal carbohydrate recognition domain, a flexible tandem-repeat neck domain, a transmembrane region and an N-terminal cytoplasmic domain involved in internalization. This gene is closely related in terms of both sequence and function to a neighboring gene, CLEC4M (Gene ID: 10332), also known as L-SIGN. The two genes differ in viral recognition and expression patterns, with this gene showing high expression on the surface of dendritic cells. Polymorphisms in the neck region are associated with protection from HIV-1 infection, while single nucleotide polymorphisms in the promoter of this gene are associated with differing resistance and susceptibility to and severity of infectious disease, including rs4804803, which is associated with SARS severity. [provided by RefSeq, May 2020]

Canonical amino-acid sequenceUniProt

404 residues, UniProt reviewed canonical sequence.

>Q9NNX6|CD209
     1  MSDSKEPRLQ QLGLLEEEQL RGLGFRQTRG YKSLAGCLGH GPLVLQLLSF TLLAGLLVQV
    61  SKVPSSISQE QSRQDAIYQN LTQLKAAVGE LSEKSKLQEI YQELTQLKAA VGELPEKSKL
   121  QEIYQELTRL KAAVGELPEK SKLQEIYQEL TWLKAAVGEL PEKSKMQEIY QELTRLKAAV
   181  GELPEKSKQQ EIYQELTRLK AAVGELPEKS KQQEIYQELT RLKAAVGELP EKSKQQEIYQ
   241  ELTQLKAAVE RLCHPCPWEW TFFQGNCYFM SNSQRNWHDS ITACKEVGAQ LVVIKSAEEQ
   301  NFLQLQSSRS NRFTWMGLSD LNQEGTWQWV DGSPLLPSFK QYWNRGEPNN VGEEDCAEFS
   361  GNGWNDDKCN LAKFWICKKS AASCSRDEEQ FLSPAPATPN PPPA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against CD209 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)
0.37
Highest tissue expression
32 nTPM

Expression across tissuesHPA

Tissue

  • adipose tissue: 32 nTPM
  • placenta: 21 nTPM
  • urinary bladder: 19 nTPM
  • small intestine: 18 nTPM
  • lymph node: 17 nTPM
  • duodenum: 13 nTPM

Single-cell type

  • macrophages: 2.7 nCPM
  • kupffer cells: 1 nCPM
  • thymocytes: 0.8 nCPM
  • cdc: 0.6 nCPM
  • podocytes: 0.3 nCPM
  • hofbauer cells: 0.2 nCPM

Immune cell

  • classical monocyte: 1.4 nTPM
  • intermediate monocyte: 1.4 nTPM
  • myeloid DC: 1.2 nTPM
  • total PBMC: 0.4 nTPM
  • basophil: 0.2 nTPM
  • neutrophil: 0.2 nTPM

Brain region

  • choroid plexus: 12 nTPM
  • cerebral cortex: 6.1 nTPM
  • cerebellum: 3.1 nTPM
  • medulla oblongata: 2.6 nTPM
  • spinal cord: 2.4 nTPM
  • pons: 2.2 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)
1.38
gnomAD pLI
0
gnomAD missense Z
-0.1
DepMap mean gene effect
0.04
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% 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

InteractionsUniProt · HPA

Protein binding partners of CD209 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 CD209 as an antibody target. Whether an autoantibody or antibody against CD209 could matter depends on whether native CD209 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

CD209 is annotated at the cell surface, where native CD209 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 CD209 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/CD209. 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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