TEC belongs to the TEC subfamily of non-receptor protein-tyrosine kinases containing a pleckstrin homology domain. TEC family kinases are involved in the intracellular signaling mechanisms of cytokine receptors, lymphocyte surface antigens, heterotrimeric G-protein coupled receptors, and integrin molecules. They are also key players in the regulation of the immune functions. TEC kinase is an integral component of T cell signaling and has a distinct role in T cell activation. TEC may be associated with myelodysplastic syndrome.