Khuchtumur Bum-Erdene, Degang Liu, Giovanni Gonzalez-Gutierrez, Mona K. Ghozayel, David Xu, Samy O. Meroueh
Proceedings of the National Academy of Science, 2020, 201913654;
DOI: 10.1073/pnas.1913654117
Ral (Ras-like) GTPases are directly activated by oncogenic Ras GTPases. Mutant K-Ras (G12C) has enabled the development of covalent K-Ras inhibitors currently in clinical trials. However, Ral, and the overwhelming majority of mutant oncogenic K-Ras, are devoid of a druggable pocket and lack an accessible cysteine for the development of a covalent inhibitor. Here, we report that covalent bond formation by an aryl sulfonyl fluoride electrophile at a tyrosine residue (Tyr-82) inhibits guanine exchange factor Rgl2-mediated nucleotide exchange of Ral GTPase. A high-resolution 1.18-Å X-ray cocrystal structure shows that the compound binds to a well-defined binding site in RalA as a result of a switch II loop conformational change. The structure, along with additional high-resolution crystal structures of several analogs in complex with RalA, confirm the importance of key hydrogen bond anchors between compound sulfone oxygen atoms and Ral backbone nitrogen atoms. Our discovery of a pocket with features found on known druggable sites and covalent modification of a bystander tyrosine residue present in Ral and Ras GTPases provide a strategy that could lead to therapeutic agent targeting oncogenic Ras mutants that are devoid of a cysteine nucleophile.
A blog highlighting recent publications in the area of covalent modification of proteins, particularly relating to covalent-modifier drugs. @CovalentMod on Twitter, @covalentmod@mstdn.science on Mastodon, and @covalentmod.bsky.social on BlueSky
Mutant-selective AKT inhibition through lysine targeting and neo-zinc chelation
Gregory B. Craven, Hang Chu, Jessica D. Sun, Jordan D. Carelli, Brittany Coyne, Hao Chen, Ying Chen, Xiaolei Ma, Subhamoy Das, Wayne Kong, A...
-
Linqi Cheng Yixian Wang, Yiming Guo, Sophie S. Zhang Han Xiao C ell Chemical Biology, 2024 Volume 31, 3, 428 - 445 https://doi.org/10.10...
-
Nathalie M. Grob, Clint Remarcik, Simon L. Rössler, Jeffrey Y. K. Wong, John C. K. Wang, Jason Tao, Corey L. Smith, Andrei Loas, Stephen L. ...
-
Guanghui Tang , Wei Wang , Chengjun Zhu , Huisi Huang , Peng Chen , Xuan Wang , Manyi Xu , Jie Sun , Chong-Jing Zhang , Qicai Xiao ...