Just published in NAR: Isoleucine-to-valine substitutions support cellular physiology during isoleucine deprivation

With substantial input of the Proteomics team of CMM (Harmjan Vos, Robert van Es and Paula Sobrevals Alcaraz), the team of Sabine Fuchs has investigated the underlying molecular mechanism of IARS1 deficiency. This enzyme belongs to the family of aminoacyl-tRNA synthetases (ARSs), enzymes that charge tRNAs with their corresponding amino acids. They conclude that isoleucine to valine substitutions by IARS1 help to prevent translational termination and maintain cellular function in human primary cells during isoleucine deprivation. These data suggest that in response to (local) amino acid deficiencies, amino acid substitutions may temporarily help preserve translational speed at the cost of translational fidelity. See link