PMID: 27139629

Authors:

Tebben AJ, Ruzanov M, Gao M, Xie D, Kiefer SE, Yan C, Newitt JA, Zhang L, Kim K, Lu H, Kopcho LM, Sheriff S

Title:

Crystal structures of apo and inhibitor-bound TGFbetaR2 kinase domain: insights into TGFbetaR isoform selectivity.

Journal:

Acta Crystallogr D Struct Biol. 2016 May;72(Pt 5):658-74. doi:, 10.1107/S2059798316003624. Epub 2016 Apr 26.

Abstract:

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.