Crystal structures of apo and inhibitor-bound TGFβR2 kinase domain: insights into TGFβR isoform selectivity

Area of Science:

• Biochemistry
• Structural Biology
• Molecular Biology

Background:

• Transforming Growth Factor-beta (TGF-β) is a crucial cytokine regulating cellular activities in development, physiology, and diseases such as cancer and fibrosis.
• TGF-β signaling involves two transmembrane serine/threonine kinase receptors: TGFβR1 and TGFβR2.
• While TGFβR1 kinase domain structures are known, TGFβR2 kinase domain structure remained elusive.

Purpose of the Study:

• To determine the high-resolution crystal structure of the TGFβR2 kinase domain.
• To provide insights into TGF-β receptor structure for targeted inhibitor design.

Main Methods:

• Engineered two mutated constructs of the TGFβR2 kinase domain to overcome crystallization challenges.
• Utilized X-ray crystallography to obtain apo and inhibitor-bound crystals diffracting to high resolution (<2 Å).

Main Results:

• Successfully determined the crystal structure of the TGFβR2 kinase domain.
• Compared TGFβR2 structures with TGFβR1, identifying shared ligand contacts and distinct ATP-binding site features.

Conclusions:

• The determined TGFβR2 kinase domain structure provides a basis for understanding TGF-β signaling.
• Structural insights facilitate the design of novel pan and selective TGFβR inhibitors for therapeutic applications.