National Center for
5E8T: TGF-BETA RECEPTOR TYPE 1 KINASE DOMAIN (T204D)
Crystal structures of apo and inhibitor-bound TGFbetaR2 kinase domain: insights into TGFbetaR isoform selectivity
Acta Crystallogr D Struct Biol (2016) 72 p.658-674
The cytokine TGF-beta modulates a number of cellular activities and plays a critical role in development, hemostasis and physiology, as well as in diseases including cancer and fibrosis. TGF-beta signals through two transmembrane serine/threonine kinase receptors: TGFbetaR1 and TGFbetaR2. Multiple structures of the TGFbetaR1 kinase domain are known, but the structure of TGFbetaR2 remains unreported. Wild-type TGFbetaR2 kinase domain was refractory to crystallization, leading to the design of two mutated constructs: firstly, a TGFbetaR1 chimeric protein with seven ATP-site residues mutated to their counterparts in TGFbetaR2, and secondly, a reduction of surface entropy through mutation of six charged residues on the surface of the TGFbetaR2 kinase domain to alanines. These yielded apo and inhibitor-bound crystals that diffracted to high resolution (<2 A). Comparison of these structures with those of TGFbetaR1 reveal shared ligand contacts as well as differences in the ATP-binding sites, suggesting strategies for the design of pan and selective TGFbetaR inhibitors.