Plant Cysteine Oxidases are Dioxygenases that Directly Enable Arginyl Transferase-Catalyzed Arginylation of N-End Rule Targets

• DOI: 10.1101/069336
• Publication Date: 2016-08-15T05:10:13Z
• Authors: Mark D. White; Maria Klecker; Richard J. Hopkinson; Daan Weits; Carolin Mueller; Christin Naumann; Rebecca O’Neill; James Wickens; Jiayu Yang; Jonathan C. Brook...; Elspeth F. Garman; Tom N. Grossman; Nico Dissmeyer; Emily Flashman
• Keywords: 580; 2. Zero hunger; 0301 basic medicine; 020; Arabidopsis Proteins; Science; Q; Arabidopsis; Cysteine Dioxygenase; 500; Aminoacyltransferases; Arginine; Article; Dioxygenases; Isoenzymes; Oxygen; 03 medical and health sciences; Journal Article; Biocatalysis; Amino Acid Sequence; Cysteine; SDG 2 - Zero Hunger; Oxidation-Reduction; info:eu-repo/classification/ddc/500

AbstractCrop yield loss due to flooding is a threat to food security. Submergence-induced hypoxia in plants results in stabilisation of group VII ETHYLENE RESPONSE FACTORS (ERF-VIIs), which aid survival under these adverse conditions. ERF-VII stability is controlled by the N-end rule pathway, which proposes that ERF-VII N-terminal cysteine oxidation in normoxia enables arginylation followed by proteasomal degradation. The PLANT CYSTEINE OXIDASEs (PCOs) have been identified as catalysts of this oxidation. ERF-VII stabilisation in hypoxia presumably arises from reduced PCO activity. We directly demonstrate that PCO dioxygenase activity produces Cys-sulfinic acid at the N-terminus of an ERF-VII peptide, which then undergoes efficient arginylation by an arginyl transferase (ATE1). This is the first molecular evidence showing N-terminal Cys-sulfinic acid formation and arginylation by N-end rule pathway components, and the first ATE1 substrate in plants. The PCOs and ATE1 may be viable intervention targets to stabilise N-end rule substrates, including ERF-VIIs to enhance submergence tolerance in agronomy.