mTORC1 cooperates with tRNA wobble modification to sustain the protein synthesis machinery

Synthesizing the cellular proteome is a demanding process that is regulated by numerous signaling pathways and RNA modifications. How these orchestrate the protein synthesis machinery to generate specific proteome subsets remains unclear. We found when mTORC1 was inactive, tRNA wobble uridine-modifying enzymes (U34-enzymes) Elongator and Ctu1/2 became essential for cell growth in vitro and in tumors. Using ribosome profiling, RNA seq and other methods, we interrogated the functional interplay between U34-enzymes and mTORC1. Overall design: Ribosome Profiling and RNAseq from EPP2 murine pancreatic cancer cell lines, with induced KO of Ctu1, were carried out to better understand the role of RNA modifications and mTORC1 in codon-specific translation. For this EPP2 cells were treated with 300 nM Torin1 or DMSO for 2 hours. For every replicate, RiboSeq and RNAseq was performed from the same sample.