title: Overexpression of lycopene ε-cyclase gene from lycium chinense confers tolerance to chilling stress in Arabidopsis thaliana.
abstract: Lutein plays an important role in protecting the photosynthetic apparatus from photodamage and eliminating ROS to render normal physiological function of cells. As a rate-limiting step for lutein synthesis in plants, lycopene ε-cyclase catalyzes lycopene to δ-carotene. We cloned a lycopene ε-cyclase gene (Lcε-LYC) from Lycium chinense (L. chinense), a deciduous woody perennial halophyte growing in various environmental conditions. The Lcε-LYC gene has an ORF of 1569bp encoding a protein of 522 aa. The deduced amino acid sequence of Lcε-LYC gene has higher homology with LycEs in other plants, such as Nicotiana tabacum and Solanum tuberosum. When L. chinense was exposed to chilling stress, relative expression of Lcε-LYC increased. To study the protective role of Lcε-LYC against chilling stress, we overexpressed the Lcε-LYC gene in Arabidopsis thaliana. Lcε-LYC overexpression led to an increase of lutein accumulation in transgenic A. thaliana, and the content of lutein decreased when transgenics were under cold conditions. In addition, the transgenic plants under chilling stress displayed higher activities of superoxide dismutase (SOD) and peroxidase (POD) and less H2O2 and malondialdehyde (MDA) than the control. Moreover, the photosynthesis rate, photosystem II activity (Fv/fm), and Non-photochemical quenching (NPQ) also increased in the transgenetic plants. On the whole, overexpression of Lcε-LYC ameliorates photoinhibition and photooxidation, and decreases the sensitivity of photosynthesis to chilling stress in transgenic plants.
authors.affiliation: School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, PR China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Song
authors.affiliation: School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China.
authors.forename: Jinjin
authors.initials: J
authors.lastname: Diao
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, PR China. Electronic address: jijing@tju.edu.cn.
authors.forename: Jing
authors.initials: J
authors.lastname: Ji
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, PR China.
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.affiliation: School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China.
authors.forename: Zhaodi
authors.initials: Z
authors.lastname: Li
authors.affiliation: School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, PR China; Department of Agronomy, Tianjin Agricultural University, 300384, PR China.
authors.forename: Jiang
authors.initials: J
authors.lastname: Wu
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, PR China.
authors.forename: Tchouopou Lontchi
authors.initials: TL
authors.lastname: Josine
authors.affiliation: Yaohua High School, Tianjin, 300072, PR China.
authors.forename: Yurong
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000222:Adaptation, Physiological / Q000235:genetics*; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D003080:Cold Temperature; D017343:Genes, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism; D019753:Intramolecular Lyases / Q000235:genetics*; D032305:Lycium / Q000201:enzymology*; D008315:Malondialdehyde / Q000378:metabolism; D010788:Photosynthesis; D030821:Plants, Genetically Modified
chemical_list: D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D019753:Intramolecular Lyases; C070925:lycopene cyclase-isomerase
keywords: Chilling stress; Lycium chinense; Lycopene ε-cyclase; Reactive oxygen species