title: Differential molecular responses of rice and wheat coleoptiles to anoxia reveal novel metabolic adaptations in amino acid metabolism for tissue tolerance.
abstract: Rice (Oryza sativa) and wheat (Triticum aestivum) are the most important starch crops in world agriculture. While both germinate with an anatomically similar coleoptile, this tissue defines the early anoxia tolerance of rice and the anoxia intolerance of wheat seedlings. We combined protein and metabolite profiling analysis to compare the differences in response to anoxia between the rice and wheat coleoptiles. Rice coleoptiles responded to anoxia dramatically, not only at the level of protein synthesis but also at the level of altered metabolite pools, while the wheat response to anoxia was slight in comparison. We found significant increases in the abundance of proteins in rice coleoptiles related to protein translation and antioxidant defense and an accumulation of a set of enzymes involved in serine, glycine, and alanine biosynthesis from glyceraldehyde-3-phosphate or pyruvate, which correlates with an observed accumulation of these amino acids in anoxic rice. We show a positive effect on wheat root anoxia tolerance by exogenous addition of these amino acids, indicating that their synthesis could be linked to rice anoxia tolerance. The potential role of amino acid biosynthesis contributing to anoxia tolerance in cells is discussed.
authors.affiliation: Australian Research Council Centre of Excellence for Plant Energy Biology, University of Western Australia, Crawley, Western Australia 6009, Australia.
authors.forename: Rachel N
authors.initials: RN
authors.lastname: Shingaki-Wells
authors.forename: Shaobai
authors.initials: S
authors.lastname: Huang
authors.forename: Nicolas L
authors.initials: NL
authors.lastname: Taylor
authors.forename: Adam J
authors.initials: AJ
authors.lastname: Carroll
authors.forename: Wenxu
authors.initials: W
authors.lastname: Zhou
authors.forename: A Harvey
authors.initials: AH
authors.lastname: Millar
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects; D000596:Amino Acids / Q000378:metabolism* / Q000494:pharmacology; D015687:Cell Hypoxia / Q000187:drug effects; D018548:Cotyledon / Q000187:drug effects / Q000201:enzymology / Q000254:growth & development / Q000502:physiology*; D019992:Databases as Topic; D000431:Ethanol / Q000378:metabolism; D005285:Fermentation / Q000187:drug effects; D006019:Glycolysis / Q000187:drug effects; D055432:Metabolomics; D012275:Oryza / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D010100:Oxygen / Q000494:pharmacology; D010101:Oxygen Consumption / Q000187:drug effects; D010641:Phenotype; D010940:Plant Proteins / Q000378:metabolism; D014176:Protein Biosynthesis / Q000187:drug effects; D040901:Proteomics; D017382:Reactive Oxygen Species / Q000378:metabolism; D014908:Triticum / Q000166:cytology / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*
chemical_list: D000596:Amino Acids; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D000431:Ethanol; D010100:Oxygen