An unconventional gatekeeper mutation sensitizes inositol hexakisphosphate kinases to an allosteric inhibitor

• DOI: 10.7554/elife.88982.3
• Publication Date: 2023-10-16T16:06:44Z
• Authors: Tim Aguirre; Gillian L Dornan; Sarah Hostachy; Martin Neuenschwa...; Carola Seyffarth; Volker Haucke; Anja Schütz; Jens Peter von Kries; Dorothea Fiedler
• Keywords: Mechanism of Action; Lead compound

Inositol hexakisphosphate kinases (IP6Ks) are emerging as relevant pharmacological targets because a multitude of disease-related phenotypes has been associated with their function. While the development potent IP6K inhibitors is gaining momentum, tool to distinguish mammalian isozymes still lacking. Here, we implemented an analog-sensitive approach for IP6Ks and performed high-throughput screen identify suitable lead compounds. The most promising hit, FMP-201300, exhibited high potency selectivity toward unique valine gatekeeper mutants IP6K1 IP6K2, compared respective wild-type (WT) kinases. Biochemical validation experiments revealed allosteric mechanism action that was corroborated by hydrogen deuterium exchange mass spectrometry measurements. latter analysis suggested displacement α C helix, caused mutation, facilitates binding FMP-201300 pocket adjacent ATP-binding site. therefore serves valuable springboard further compounds can selectively target three IP6Ks; either kinase or compound WT