CD247that

CD247that is not a recognized term in major biological databases and is likely a typographical variant or nonstandard alias of CD247. CD247, commonly referred to as the CD3 zeta chain (CD3Z), is a gene that encodes a transmembrane protein essential for T-cell receptor (TCR) signaling. The CD3 zeta chain is a core component of the TCR-CD3 complex, pairing with the CD3 gamma, delta, and epsilon chains to form the signaling unit that activates T cells upon antigen recognition.

Structure and function

The CD3 zeta chain is a transmembrane protein with a short extracellular domain and a long cytoplasmic tail containing ITAM motifs (immunoreceptor tyrosine-based activation motifs). Each CD3 zeta chain harbors three ITAMs, and the TCR-CD3 complex contains two zeta chains, providing a total of six ITAMs for signal amplification. Upon antigen engagement, the ITAMs become phosphorylated by kinases such as Lck, recruiting ZAP-70 and other signaling molecules. This initiates downstream cascades that lead to T-cell activation, proliferation, cytokine production, and effector differentiation.

Expression and significance

CD247 is primarily expressed in T lymphocytes and natural killer (NK) cells, with expression detectable during thymocyte development. It is indispensable for effective TCR signaling and normal T-cell maturation. Defects in CD247 or diminished CD3 zeta expression can result in impaired T-cell responses and immunodeficiency. Altered CD3 zeta expression has also been observed in various clinical contexts, including chronic infections and inflammatory states, where it may reflect T-cell functional status.

Note

If the intended topic was CD247 (the CD3 zeta chain), the above applies. If "CD247that" refers to a different or newly named entity, please provide clarification or a reference point for a more precise entry.