P20963

CD3ζ also known as CD3Z, CD247 is T-cell receptor zeta, which together with T-cell receptor alpha/beta and gamma/delta heterodimers, and with CD3-gamma, -delta and -epsilon, forms the T-cell receptor-CD3 complex. CD3ζ plays a crucial role in T cell activation, as CD3ζ is part of the T cell receptor (TCR) complex that transmits signals upon recognition of foreign antigens. This signaling is essential for the immune response, as CD3ζ leads to the activation of T cells, which are vital for adaptive immunity. The CD3 complex, which includes CD3ζ, consists of five invariant polypeptide chains that form three distinct dimers, facilitating the transmission of activation signals. The ζ chain contains three immunoreceptor tyrosine-based activation motifs (ITAMs), which are critical for recruiting protein kinases like ZAP-70 and Syk, thereby amplifying the signaling cascade that results in T cell activation. The structural integrity and phosphorylation state of these motifs are vital for effective immune responses, making CD3-ζ a key player in immunological signaling pathways.