Homo sapiens Protein: CD209
InnateDB Protein IDBP-23416.6
Last Modified 2014-10-13 [Report errors or provide feedback]
Gene Symbol CD209
Protein Name CD209 molecule
Species Homo sapiens
Ensembl Protein ENSP00000315477
InnateDB Gene IDBG-23414 (CD209)
Protein Structure
UniProt Annotation
Function Pathogen-recognition receptor expressed on the surface of immature dendritic cells (DCs) and involved in initiation of primary immune response. Thought to mediate the endocytosis of pathogens which are subsequently degraded in lysosomal compartments. The receptor returns to the cell membrane surface and the pathogen-derived antigens are presented to resting T-cells via MHC class II proteins to initiate the adaptive immune response. Probably recognizes in a calcium-dependent manner high mannose N-linked oligosaccharides in a variety of pathogen antigens, including HIV-1 gp120, HIV-2 gp120, SIV gp120, ebolavirus glycoproteins, cytomegalovirus gB, HCV E2, dengue virus gE, Leishmania pifanoi LPG, Lewis-x antigen in Helicobacter pylori LPS, mannose in Klebsiella pneumonae LPS, di-mannose and tri- mannose in Mycobacterium tuberculosis ManLAM and Lewis-x antigen in Schistosoma mansoni SEA.On DCs it is a high affinity receptor for ICAM2 and ICAM3 by binding to mannose-like carbohydrates. May act as a DC rolling receptor that mediates transendothelial migration of DC presursors from blood to tissues by binding endothelial ICAM2. Seems to regulate DC-induced T-cell proliferation by binding to ICAM3 on T-cells in the immunological synapse formed between DC and T-cells.
Subcellular Localization Isoform 1: Cell membrane {ECO:0000305}; Single-pass type II membrane protein {ECO:0000305}.Isoform 2: Cell membrane {ECO:0000305}; Single-pass type II membrane protein {ECO:0000305}.Isoform 3: Cell membrane {ECO:0000305}; Single-pass type II membrane protein {ECO:0000305}.Isoform 4: Cell membrane {ECO:0000305}; Single-pass type II membrane protein {ECO:0000305}.Isoform 5: Cell membrane {ECO:0000305}; Single-pass type II membrane protein {ECO:0000305}.Isoform 6: Secreted {ECO:0000305}.Isoform 7: Secreted {ECO:0000305}.Isoform 8: Secreted {ECO:0000305}.Isoform 9: Secreted {ECO:0000305}.Isoform 10: Secreted {ECO:0000305}.Isoform 11: Secreted {ECO:0000305}.Isoform 12: Secreted {ECO:0000305}.
Disease Associations
Tissue Specificity Predominantly expressed in dendritic cells and in DC-residing tissues. Also found in placental macrophages, endothelial cells of placental vascular channels, peripheral blood mononuclear cells, and THP-1 monocytes. {ECO:0000269PubMed:11257134, ECO:0000269PubMed:11337487}.
Number of Interactions This gene and/or its encoded proteins are associated with 11 experimentally validated interaction(s) in this database.
They are also associated with 1 interaction(s) predicted by orthology.
Experimentally validated
Total 11 [view]
Protein-Protein 10 [view]
Protein-DNA 1 [view]
Protein-RNA 0
Predicted by orthology
Total 1 [view]
Gene Ontology

Molecular Function
Accession GO Term
GO:0005515 protein binding
GO:0005537 mannose binding
GO:0030246 carbohydrate binding
GO:0042605 peptide antigen binding
GO:0046790 virion binding
GO:0046872 metal ion binding
Biological Process
GO:0006897 endocytosis
GO:0007157 heterophilic cell-cell adhesion
GO:0007159 leukocyte cell-cell adhesion
GO:0009988 cell-cell recognition
GO:0019048 modulation by virus of host morphology or physiology
GO:0019062 virion attachment to host cell
GO:0019079 viral genome replication
GO:0019882 antigen processing and presentation
GO:0035556 intracellular signal transduction
GO:0042129 regulation of T cell proliferation
GO:0045087 innate immune response (InnateDB)
GO:0046968 peptide antigen transport
GO:0075733 intracellular transport of virus
Cellular Component
GO:0005737 cytoplasm
GO:0005886 plasma membrane
GO:0016020 membrane
GO:0016021 integral component of membrane
GO:0070062 extracellular vesicular exosome
Protein Structure and Domains
InterPro IPR001304 C-type lectin
IPR002353 Type-2 ice-structuring protein
IPR016187 C-type lectin fold
PFAM PF00059
Post-translational Modifications
SwissProt Q9NNX6
PhosphoSite PhosphoSite-Q9NNX6
UniProt Splice Variant
Entrez Gene 30835
UniGene Hs.278694
RefSeq NP_066978
OMIM 604672
HPRD 05241
EMBL AC008763 AC008812 AF209479 AF290886 AK293089 AK304190 AY042221 AY042222 AY042223 AY042224 AY042225 AY042226 AY042227 AY042228 AY042229 AY042230 AY042231 AY042232 AY042233 BC110615 CH471139 M98457
GenPept AAF77072 AAG13814 AAI10616 AAK20997 AAK91846 AAK91847 AAK91848 AAK91849 AAK91850 AAK91851 AAK91852 AAK91853 AAK91854 AAK91855 AAK91856 AAK91857 AAK91858 BAF85778 BAG65070 EAW68991 EAW68993 EAW68997 EAW68998