TY - JOUR T1 - Ncl1-mediated metabolic rewiring critical during metabolic stress JF - Life Science Alliance JO - Life Sci. Alliance DO - 10.26508/lsa.201900360 VL - 2 IS - 4 SP - e201900360 AU - Ajay Bhat AU - Rahul Chakraborty AU - Khushboo Adlakha AU - Ganesh Agam AU - Kausik Chakraborty AU - Shantanu Sengupta Y1 - 2019/08/01 UR - https://www.life-science-alliance.org/content/2/4/e201900360.abstract N2 - Nutritional limitation has been vastly studied; however, there is limited knowledge of how cells maintain homeostasis in excess nutrients. In this study, using yeast as a model system, we show that some amino acids are toxic at higher concentrations. With cysteine as a physiologically relevant example, we delineated the pathways/processes that are altered and those that are involved in survival in the presence of elevated levels of this amino acid. Using proteomics and metabolomics approach, we found that cysteine up-regulates proteins involved in amino acid metabolism, alters amino acid levels, and inhibits protein translation—events that are rescued by leucine supplementation. Through a comprehensive genetic screen, we show that leucine-mediated effect depends on a transfer RNA methyltransferase (NCL1), absence of which decouples transcription and translation in the cell, inhibits the conversion of leucine to ketoisocaproate, and leads to tricarboxylic acid cycle block. We therefore propose a role of NCL1 in regulating metabolic homeostasis through translational control. ER -