Figure 1From: Ibrutinib and novel BTK inhibitors in clinical developmentBTK structure. BTK belongs to the Tec family of protein tyrosine kinases and is composed of the PH (pleckstrin homology), TH (Tec homology), SH3 (Src homology 3) SH2 (Src homology 2), and SH 1/TK (Src homology1/Tyrosine kinase) domains. Binding sites for BTK substrates, inhibitors, and upstream molecules are shown in the diagram.Back to article page