title: Hot air treatment-induced arginine catabolism is associated with elevated polyamines and proline levels and alleviates chilling injury in postharvest tomato fruit.
abstract: BACKGROUND
  To understand whether arginine catabolism might be involved in hot air (HA)-induced chilling tolerance mechanism in tomato fruit, we investigated the effect of HA treatment on endogenous arginine catabolism in relation to chilling injury.
  
  
  RESULTS
  Tomato fruit were harvested at mature green stage and treated with HA at 38°C for 12 h and then stored at 2°C for 21 days. The effects of HA treatment on fruit chilling injury and gene expression levels or enzyme activity, and metabolites related to arginine catabolism were evaluated. HA treatment reduced the chilling injury symptoms of tomato fruit and enhanced the accumulation of endogenous polyamines, especially putrescine and proline. This accumulation is associated with the increased transcript levels of genes encoding arginase (LeARG1 and LeARG2), arginine decarboxylase (LeADC), ornithine decarboxylase (LeODC) and ornithine aminotransferase (LeOAT) at most sampling times. However, HA treatment had little effect on nitric oxide synthase activity and nitric oxide concentration.
  
  
  CONCLUSIONS
  These results revealed that the reduction in chilling injury by HA treatment may be due to the accumulation of putrescine and proline induced primarily by activating the catabolism of endogenous arginine.
authors.affiliation: School of Agricultural and Food Engineering, Shandong University of Technology, Zibo, 255049, Shandong, People's Republic of China; College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, 100083, People's Republic of China.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Shen
authors.forename: Fujun
authors.initials: F
authors.lastname: Li
authors.forename: Demei
authors.initials: D
authors.lastname: Meng
authors.forename: Jiping
authors.initials: J
authors.lastname: Sheng
mesh_terms: D001119:Arginase / Q000235:genetics / Q000378:metabolism; D001120:Arginine / Q000378:metabolism*; D002262:Carboxy-Lyases / Q000235:genetics / Q000378:metabolism; D003080:Cold Temperature / Q000009:adverse effects*; D005519:Food Preservation / Q000379:methods; D005638:Fruit / Q000737:chemistry / Q000201:enzymology / Q000378:metabolism; D015870:Gene Expression; D006358:Hot Temperature; D018551:Solanum lycopersicum / Q000378:metabolism*; D009569:Nitric Oxide / Q000032:analysis; D009955:Ornithine Decarboxylase / Q000235:genetics; D009953:Ornithine-Oxo-Acid Transaminase / Q000235:genetics; D011073:Polyamines / Q000032:analysis*; D011392:Proline / Q000032:analysis* / Q000378:metabolism; D011700:Putrescine / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D011073:Polyamines; D012333:RNA, Messenger; D009569:Nitric Oxide; D001120:Arginine; D011392:Proline; D009953:Ornithine-Oxo-Acid Transaminase; D001119:Arginase; D002262:Carboxy-Lyases; D009955:Ornithine Decarboxylase; C019722:arginine decarboxylase; D011700:Putrescine
keywords: arginine catabolism; chilling injury (CI); hot air (HA); polyamines (PAs); proline; tomato fruit