PT  - JOURNAL ARTICLE
AU  - Mark D. White
AU  - Maria Klecker
AU  - Richard J. Hopkinson
AU  - Daan Weits
AU  - Carolin Mueller
AU  - Christin Naumann
AU  - Rebecca O’Neill
AU  - James Wickens
AU  - Tom N. Grossmann
AU  - Nico Dissmeyer
AU  - Emily Flashman
TI  - Plant Cysteine Oxidases are Dioxygenases that Directly Enable Arginyl Transferase-Catalyzed Arginylation of N-End Rule Targets
AID  - 10.1101/069336
DP  - 2016 Jan 01
TA  - bioRxiv
PG  - 069336
4099  - http://biorxiv.org/content/early/2016/08/14/069336.short
4100  - http://biorxiv.org/content/early/2016/08/14/069336.full
AB  - Crop 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 the 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 catalysing 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 cysteine oxidation 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.Abbreviations PCO, plant cysteine oxidase; ATE, arginyl tRNA transferase; ERF-VII, group VII ETHYLENE RESPONSE FACTOR; 2OG, 2-oxoglutarate; NMR, nuclear magnetic resonance; Met, methionine; NME, N-terminal Met excision; Nt, N-terminal; NO, nitric oxide; HIF, hypoxia-inducible factor; PHD, prolyl hydroxylase; MALDI-MS, matrix-assisted laser desorption/ionization-mass spectrometry; LC-MS, liquid chromatography-mass spectrometry; HRE, HYPOXIA RESPONSIVE ERF; RAP, RELATED TO APETALA2; EBP, ETHYLENE RESPONSE FACTOR 72; CDO, cysteine dioxygenase; MAP, Met-aminopeptidase.