TXK is a non-receptor tyrosine kinase of the Tec family that plays a crucial role in T-cell signaling and adaptive immune responses. Unlike other Tec kinases, TXK lacks a pleckstrin homology domain and instead contains a palmitoylated cysteine-string motif for membrane localization 1. TXK is activated through phosphorylation by Src family kinases following T-cell receptor stimulation and associates with lipid rafts independently of PI-3K activity 1. A key mechanism involves TXK's role as a transcription factor that forms a trimolecular complex with poly(ADP-ribose) polymerase 1 (PARP1) and elongation factor 1α (EF-1α) 2. This complex translocates to the nucleus upon T-cell activation and binds to the interferon-γ gene promoter, specifically regulating IFN-γ transcription in Th1 cells 2. TXK expression is enhanced in Th1-dominant autoimmune diseases including rheumatoid arthritis and Behçet's disease, where excessive TXK expression correlates with increased IFN-γ production and skewed Th1 responses 34. The kinase compensates partially for ITK loss, suggesting functional redundancy in T-cell development 1. Additionally, TXK has been identified in fusion genes in angioleiomyomas, indicating potential oncogenic roles 5.