T cell receptor alpha joining 45 (TRAJ45)

T cell receptor alpha joining 45 (TRAJ45) is a joining (J) gene segment within the TCR alpha (TRA) locus, used during VJ recombination. This process, essential for the adaptive immune system, allows for the assembly of diverse T cell receptors capable of recognizing a broad range of antigens. While the TRAJ45 segment contributes to receptor diversity, it is not a standalone receptor or protein target; it functions at the DNA level during T cell development in the thymus. The actual protein receptor expressed on T cells is the *T cell receptor alpha/beta heterodimer*, encoded by multiple *variable (V)*, *joining (J)* (like TRAJ45), and *constant (C)* gene segments. Individual J segments such as TRAJ45 do not have a function outside of facilitating the recombination process that generates TCR diversity; they are not independent targets in drug development or clinical practice. TRAJ45 is a genetic joining segment used to build the antigen-recognition domain of the T cell receptor alpha chain. It is not considered a therapeutic target, biomarker, or standalone protein, nor does it directly interact with drugs or confer safety concerns. It has no independent disease associations but is integral to the general function of T cell immunity.

Other names

TRAJ45TCR alpha J45 segment