TXK (gene)

TXK, also known as T-cell tyrosine kinase, is a non-receptor tyrosine kinase belonging to the TEC family of kinases. These kinases play critical roles in signaling pathways downstream of cell surface receptors, particularly in immune cells.

TXK is predominantly expressed in T cells and natural killer (NK) cells, where it participates in T cell receptor (TCR) and NK cell receptor signaling. It is crucial for T cell development, activation, and effector function.

The TXK protein contains several conserved domains, including an N-terminal pleckstrin homology (PH) domain, a Tec homology (TH) domain, an SH3 domain, an SH2 domain, and a tyrosine kinase domain. These domains mediate protein-protein interactions and regulate kinase activity.

Upon TCR engagement, TXK is recruited to the immunological synapse, where it becomes activated by phosphorylation. Activated TXK then phosphorylates downstream targets, initiating signaling cascades that lead to T cell proliferation, cytokine production, and cytotoxicity.

Dysregulation of TXK activity has been implicated in various immune-related diseases, including autoimmune disorders and cancer. Genetic variations in the TXK gene may influence susceptibility to these diseases. Research into TXK and its signaling pathways is ongoing to further elucidate its role in immune regulation and to explore potential therapeutic targets.