||Evaluation of metabolic changes in oxalate-rich plant Rumex obtusifolius L. caused by ion beam irradiation.
Miyagi, Atsuko ,
Kitano, Sayaka ,
大野, 豊 ,
長谷, 純宏 ,
Narumi, Issay ,
Yamaguchi, Masatoshi ,
Uchimiya, HirofumiMaki, Kawai-Yamada
Plant Physiology and Biochemistry
45 , 2018-01
Some Rumex species such as sorrel are edible as baby leaf salad. On the other hand, Rumex plants accumulate soluble oxalate, a toxic metabolite which causes serious diseases such as renal syndrome. We attempted to produce low-oxalate plants of R. obtusifolius, a perennial weed which has higher vitamin C and amino acid content and higher tolerance to stress than many other Rumex species. In a previous study, we revealed a decrease in oxalate content of leaves of R. obtusifolius obtained from seeds irradiated with gamma rays (Kitano et al. 2015). Ion beams are also ionising radiation with high linear energy transfer that causes a wide spectrum of mutations. Thus, in the present study we evaluated the effects of ion beams on oxalate and other primary metabolites in leaves of R. obtusifolius using capillary electrophoresis-mass spectrometry. Unlike previous results obtained with gamma rays, the oxalate content was increased by irradiation with carbon ion beams. Metabolome analysis revealed that both ion beams and gamma rays affected carbon flow to the isocitrate pathway, which is involved in oxalate synthesis. These observations suggested that modulation of carbon flow to the isocitrate pathway is important to regulate oxalate levels in plants.