CD8A

T-cell surface glycoprotein CD8 alpha chain (Cluster of Differentiation 8a), is a protein encoded by CD8A gene.^[5]

CD8A
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1AKJ, 1CD8, 1Q69, 2HP4, 3QZW
Identifiers
Aliases	CD8A, CD8, Leu2, MAL, p32, CD8a molecule
External IDs	OMIM: 186910; MGI: 88346; HomoloGene: 133777; GeneCards: CD8A; OMA:CD8A - orthologs
Gene location (Human) Chr. Chromosome 2 (human)[1] Band 2p11.2 Start 86,784,610 bp[1] End 86,808,396 bp[1]
Gene location (Mouse) Chr. Chromosome 6 (mouse)[2] Band 6 C1|6 32.14 cM Start 71,350,411 bp[2] End 71,356,157 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in thymus spleen granulocyte blood superficial temporal artery lymph node jejunal mucosa appendix bone marrow bone marrow cell Top expressed in thymus mesenteric lymph nodes blood spleen subcutaneous adipose tissue duodenum embryo jejunum sternocleidomastoid muscle lumbar subsegment of spinal cord More reference expression data BioGPS More reference expression data
Gene ontology Molecular function coreceptor activity protein binding MHC class I protein binding protein kinase binding MHC class I protein complex binding Cellular component integral component of membrane membrane plasma membrane integral component of plasma membrane T cell receptor complex extracellular region plasma membrane raft external side of plasma membrane Biological process antigen processing and presentation adaptive immune response transmembrane receptor protein tyrosine kinase signaling pathway immune system process immune response regulation of immune response T cell activation T cell mediated immunity cell surface receptor signaling pathway cytotoxic T cell differentiation Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 925 12525 Ensembl ENSG00000153563 ENSMUSG00000053977 UniProt P01732 P01731 RefSeq (mRNA) NM_001145873 NM_001768 NM_171827 NM_001081110 NM_009857 RefSeq (protein) NP_001139345 NP_001759 NP_741969 NP_001369627 NP_001074579 NP_033987 Location (UCSC) Chr 2: 86.78 – 86.81 Mb Chr 6: 71.35 – 71.36 Mb PubMed search [3] [4]
Wikidata
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Function

The CD8 protein is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within the immune system. The CD8, acting as a coreceptor, and the T-cell receptor on the T lymphocyte recognize antigen displayed by an antigen-presenting cell (APC) in the context of class I MHC molecules. The functional coreceptor is either a homodimer composed of two alpha chains, or a heterodimer composed of one alpha and one beta chain. Both alpha and beta chains share significant homology to variable domain of immunoglobulin light chains. This gene encodes the CD8 alpha chain isoforms. Two alternative transcripts encoding distinct isoforms, one membrane associated and one secreted, have been identified.^[5]

Interactions

CD8A has been shown to interact with:

• CD3D,^[6]
• HLA-A,^[7][8] and
• HLA-G.^[7][9]

See also

• Cluster of differentiation