https://doi.org/10.1351/goldbook.13049
Cell surface protein receptor that recognizes a substance bound to a primary receptor, and binds to a signaling molecule that thereby enhances the activity of another receptor.
Notes:
- Optimal T cell activation in an immune response depends on the involvement of relevant coreceptors occurring in a cluster with the T-cell receptors (TCRs). The coreceptors are CD4 or CD8 proteins, which lie alongside the T-cell receptor in the plasma membrane. Only when both coreceptor and receptor bind the major histocompatibility complex (MHC) molecule-antigen complex simultaneously is the full set of intracellular effector molecules recruited and the signal pathway inside the cell maximally activated.
- B-cell receptors (BCRs) require the contributions of several coreceptors, notably CD19, CD21, and CD81 proteins, for full activation of intracellular signaling pathways.