Discovery of Lysine-Targeted eIF4E Inhibitors through Covalent Docking
Xiaobo Wan, Tangpo Yang, Adolfo Cuesta, Xiaming Pang, Trent E. Balius, John J. Irwin, Brian K. Shoichet, Jack Taunton
Abstract
Eukaryotic translation initiation factor 4E (eIF4E) binds the m7GTP cap structure at the 5′-end of mRNAs, stimulating the translation of proteins implicated in cancer cell growth and metastasis. eIF4E is a notoriously challenging target, and most of the reported inhibitors are negatively charged guanine analogues with negligible cell permeability. To overcome these challenges, we envisioned a covalent targeting strategy. As there are no cysteines near the eIF4E cap binding site, we developed a covalent docking approach focused on lysine. Taking advantage of a “make-on-demand” virtual library, we used covalent docking to identify arylsulfonyl fluorides that target a noncatalytic lysine (Lys162) in eIF4E. Guided by cocrystal structures, we elaborated arylsulfonyl fluoride 2 to 12, which to our knowledge is the first covalent eIF4E inhibitor with cellular activity. In addition to providing a new tool for acutely inactivating eIF4E in cells, our computational approach may offer a general strategy for developing selective lysine-targeted covalent ligands.