Potent human ClpP protease agonists with anticancer properties bind the enzyme with improved structural complementarity and alter the mitochondrial N-terminome

Abstract The mitochondrial ClpP protease is responsible for mitochondrial protein quality control through specific degradation of proteins involved in several metabolic processes. ClpP overexpression is also required in many cancer cells to eliminate ROS-damaged proteins and to sustain oncogenesis. Targeting ClpP to dysregulate its function using small molecule agonists is a novel strategy in cancer therapy. Here, we synthesized novel imipridone-derived compounds and related chemicals, which we characterized using biochemical, biophysical, and cellular studies. Using X-ray crystallography, we found that these compounds have enhanced binding affinities due to their greater shape and charge complementarity with the surface hydrophobic pockets of ClpP. N-terminome profiling of cancer cells upon treatment with one of these compounds revealed the global proteomic changes that arise and identified the structural motifs preferred for protein cleavage by compound-activated ClpP. Together, our studies provide the structural and molecular bases by which dysregulated ClpP affects cancer cell viability and proliferation. Citation Format: Mark F. Mabanglo, Keith S. Wong, Marim M. Barghash, Lee M. Graves, Edwin J. Iwanowicz, Walid A. Houry. Potent human ClpP protease agonists with anticancer properties bind the enzyme with improved structural complementarity and alter the mitochondrial N-terminome. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3843.