Inhibition of mutant RAS-RAF interaction by mimicking structural and dynamic properties of phosphorylated RAS
Undruggability of RAS proteins has necessitated alternative strategies for the development of effective inhibitors. In this respect, phosphorylation has recently come into prominence as this reversible post-translational modification attenuates sensitivity of RAS towards RAF. As such, in this study, we set out to unveil the impact of phosphorylation on dynamics of HRASWT and aim to invoke similar behavior in HRASG12D mutant by means of small therapeutic molecules. To this end, we performed molecular dynamics (MD) simulations using phosphorylated HRAS and showed that phosphorylation of Y32 distorted Switch I, hence the RAS/RAF interface. Consequently, we targeted Switch I in HRASG12D by means of approved therapeutic molecules and showed that the ligands enabled detachment of Switch I from the nucleotide-binding pocket. Moreover, we demonstrated that displacement of Switch I from the nucleotide-binding pocket was energetically more favorable in the presence of the ligand. Importantly, we verified computational findings in vitro where HRASG12D/RAF interaction was prevented by the ligand in HEK293T cells that expressed HRASG12D mutant protein. Therefore, these findings suggest that targeting Switch I, hence making Y32 accessible might open up new avenues in future drug discovery strategies that target mutant RAS proteins.
Simulated data used to generate the figures in the commentary are available online (https://osf.io/z2y5s/?view_only=070ebb995ba945bb9aac40d5979bd508).
Article and author information
Health Institute of Turkey (3561/2019-TA-02)
- Metehan Ilter
- Ozan Topcu
- Ozge Sensoy
The Scientific and Technological Research Council of Turkey (116F229)
- Farzaneh Jalalypour
- Canan Atilgan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Qiang Cui, Boston University, United States
- Preprint posted: April 24, 2022 (view preprint)
- Received: April 25, 2022
- Accepted: November 30, 2022
- Accepted Manuscript published: December 2, 2022 (version 1)
- Accepted Manuscript updated: December 5, 2022 (version 2)
- Version of Record published: December 19, 2022 (version 3)
© 2022, Ilter et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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