title: ICE1 of Poncirus trifoliata functions in cold tolerance by modulating polyamine levels through interacting with arginine decarboxylase.
abstract: ICE1 (Inducer of CBF Expression 1) encodes a MYC-like basic helix-loop-helix transcription factor that acts as a central regulator of cold response. In this study, we elucidated the function and underlying mechanisms of PtrICE1 from trifoliate orange [Poncirus trifoliata (L.) Raf.]. PtrICE1 was upregulated by cold, dehydration, and salt, with the greatest induction under cold conditions. PtrICE1 was localized in the nucleus and could bind to a MYC-recognizing sequence. Ectopic expression of PtrICE1 in tobacco and lemon conferred enhanced tolerance to cold stresses at either chilling or freezing temperatures. Yeast two-hybrid screening revealed that 21 proteins belonged to the PtrICE1 interactome, in which PtADC (arginine decarboxylase) was confirmed as a bona fide protein interacting with PtrICE1. Transcript levels of ADC genes in the transgenic lines were slightly elevated under normal growth condition but substantially increased under cold conditions, consistent with changes in free polyamine levels. By contrast, accumulation of the reactive oxygen species, H2O2 and O2 (-), was appreciably alleviated in the transgenic lines under cold stress. Higher activities of antioxidant enzymes, such as superoxide dismutase and catalase, were detected in the transgenic lines under cold conditions. Taken together, these results demonstrated that PtrICE1 plays a positive role in cold tolerance, which may be due to modulation of polyamine levels through interacting with the ADC gene.
authors: Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors: Xiao-San
authors: XS
authors: Huang
authors: Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors: Qinghua
authors: Q
authors: Zhang
authors: Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors: Dexin
authors: D
authors: Zhu
authors: Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors: Xingzheng
authors: X
authors: Fu
authors: Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors: Min
authors: M
authors: Wang
authors: Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China.
authors: Qian
authors: Q
authors: Zhang
authors: National Institute of Fruit Tree Science, Tsukuba 305-8605, Japan.
authors: Takaya
authors: T
authors: Moriguchi
authors: Key Laboratory of Horticultural Plant Biology (MOE), College of Horticulture and Forestry Science, Huazhong Agricultural University, Wuhan 430070, PR China liujihong@mail.hzau.edu.cn.
authors: Ji-Hong
authors: JH
authors: Liu
mesh_terms: D000222:Adaptation, Physiological; D001483:Base Sequence; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism*; D002262:Carboxy-Lyases / Q000235:genetics / Q000378:metabolism*; D002957:Citrus / Q000201:enzymology / Q000235:genetics / Q000502:physiology; D003080:Cold Temperature; D018506:Gene Expression Regulation, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D030821:Plants, Genetically Modified; D011073:Polyamines / Q000378:metabolism*; D032104:Poncirus / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism; D017422:Sequence Analysis, DNA; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological; D014026:Nicotiana / Q000201:enzymology / Q000235:genetics / Q000502:physiology
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D002262:Carboxy-Lyases; D006861:Hydrogen Peroxide; D010940:Plant Proteins; D011073:Polyamines; D017382:Reactive Oxygen Species; D012965:Sodium Chloride; C019722:arginine decarboxylase
keywords: Poncirus trifoliata (L.) Raf.; ROS; bHLH; cold tolerance; polyamine; protein-interacting protein; transcription factor.