The CD8 antigen is a cell surface glycoprotein found on most cytotoxic T lymphocytes that mediates efficient cell-cell interactions within the immune system. The CD8 antigen, 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 immunoglobulin variable 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]
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Overview of all the structural information available in the PDB for UniProt: P01732 (Human T-cell surface glycoprotein CD8 alpha chain) at the PDBe-KB.
Overview of all the structural information available in the PDB for UniProt: P01731 (Mouse T-cell surface glycoprotein CD8 alpha chain) at the PDBe-KB.
PDB gallery
1akj: COMPLEX OF THE HUMAN MHC CLASS I GLYCOPROTEIN HLA-A2 AND THE T CELL CORECEPTOR CD8
1cd8: CRYSTAL STRUCTURE OF A SOLUBLE FORM OF THE HUMAN T CELL CO-RECEPTOR CD8 AT 2.6 ANGSTROMS RESOLUTION
2hp4: Computational design and crystal structure of an enhanced affinity mutant human CD8-alpha-alpha co-receptor