FTSJ1 INHIBITION AS A STRATEGY FOR NONSENSE MUTATION SUPPRESSION IN TP53: INTEGRATIVE COMPUTATIONAL AND EXPERIMENTAL ANALYSIS

Abstract

Nonsense mutations are single-nucleotide substitutions that convert sense codons into premature termination codons (PTCs), resulting in truncated, non-functional proteins. These mutations contribute to approximately 11% of all genetic disorders and affect nearly 12% of tumor suppressor genes, including TP53, one of the most frequently mutated genes in human cancers [1]. The TP53 gene encodes the tumor suppressor protein p53, a central regulator of cell cycle arrest, apoptosis, and genomic stability. Notably, around 10% of TP53 mutations are classified as nonsense mutations, underscoring the need for targeted therapeutic interventions [2]. Translational readthrough (RT)-based therapy represents a promising strategy to restore protein function by promoting the bypass of PTCs during translation. This approach employs small molecules known as translational readthrough-inducing drugs (TRIDs) to facilitate the synthesis of full-length, functional proteins. The tRNA-specific 2′-O-methyltransferase FTSJ1, which catalyzes the methylation of cytosine 34 in tRNA^Trp and influences the decoding of UGA stop codons, has recently emerged as a regulatory node in translation and a potential therapeutic target in oncology [3]. In this study, we identified novel chemical scaffolds capable of enhancing translational readthrough of nonsense-mutated TP53 by selectively targeting FTSJ1. We implemented a structure-based virtual screening workflow integrating molecular docking, binding pose metadynamics, MM-GBSA free energy estimations, and molecular dynamics simulations to prioritize candidate TRIDs. The top-ranked compounds were subsequently evaluated in vitro for their capacity to restore full-length p53 protein expression. Our findings highlight the therapeutic potential of FTSJ1-targeting TRIDs as a novel class of agents for the treatment of cancers harboring TP53 nonsense mutations.