PTK2B/PYK2

PTK2B encodes PYK2 (proline-rich tyrosine kinase 2, also called FAK2, CAKβ or RAFTK), the second member of the FAK family. PYK2 shares the FERM-kinase-FAT domain architecture with FAK but lacks an autoinhibitory interaction, rendering it more readily activated by diverse stimuli. Its expression is prominent in the central nervous system and hematopoietic cells. PYK2 is strongly activated by calcium influx and by G-protein-coupled receptors, integrating neuronal excitation, chemokine signaling and osteoclast cytoskeletal remodeling; it contributes to synaptic plasticity, microglial motility and bone resorption. Dysregulated PYK2 participates in anxiety-related behavior, leukemia cell migration and solid tumor metastasis. FAK-family inhibitors generally target both FAK and PYK2, complicating therapeutic attribution of their effects.