Identifies cytotoxic/suppressor T-cells that interact with MHC class I bearing targets. CD8 is thought to play a role in the process of T-cell mediated killing. CD8 alpha chains binds to class I MHC molecules alpha-3 domains. In general heterodimer of an alpha and a beta chain linked by two disulfide bonds. Can also form homodimers. Shown to be expressed as heterodimer on thymocytes and as homodimer on peripheral blood T-lymphocytes. Interacts with the MHC class I HLA-A/B2M dimer. Interacts with LCK in a zinc-dependent manner. 2 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.
Cellular Component: T cell receptor complex; integral to plasma membrane; plasma membrane; extracellular region; external side of plasma membrane
Molecular Function: protein binding; protein homodimerization activity; MHC class I protein binding; coreceptor activity; protein kinase binding
Biological Process: antigen processing and presentation; regulation of immune response; T cell activation; T cell mediated immunity; positive regulation of calcium-mediated signaling; cytotoxic T cell differentiation; immune response; defense response to virus; transmembrane receptor protein tyrosine kinase signaling pathway
SS: The number of records in which this modification site was determined using site-specific methods. SS methods include amino acid sequencing, site-directed mutagenesis, modification site-specific antibodies, specific MS strategies, etc.