title: Plastid signals confer Arabidopsis tolerance to water stress.
abstract: Plastid-to-nucleus retrograde signalling coordinates nuclear gene expression with chloroplast function and is essential for the photoautotrophic life-style of plants. The relationship between plastid signalling and water stress response was investigated with genome uncoupled (gun) mutants, gun1, gun3, and gun5, and an abscisic acid (ABA)-responsible transcription factor mutant, abi4. The results showed that gun1, gun3, gun5, and abi4 mutants suffered from more oxidative damages than the wild-type plants under the water stress and the water stress + herbicide (norflurazon, NF) co-treatment. Superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) activities could not be prompted in the plastid-signalling defective mutants under the stress conditions. At the same time, Lhcb expression was not repressed in the plastid-signalling defective mutants by the NF treatment or water stress. Therefore, the photosynthetic apparatus in the mutant cells could not be closed during the stresses and the excessive light caused more photodamages on the mutant leaves. The roles of GUN1, GUN3, GUN5 and ABI4 proteins in environmental stress adaptation have been discussed.
authors.affiliation: Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment, College of Life Science, Sichuan University, Chengdu 610064, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Cheng
authors.forename: Chun-Xia
authors.initials: CX
authors.lastname: He
authors.forename: Zhong-Wei
authors.initials: ZW
authors.lastname: Zhang
authors.forename: Fei
authors.initials: F
authors.lastname: Xu
authors.forename: Da-Wei
authors.initials: DW
authors.lastname: Zhang
authors.forename: Xiao
authors.initials: X
authors.lastname: Wang
authors.forename: Shu
authors.initials: S
authors.lastname: Yuan
authors.forename: Hong-Hui
authors.initials: HH
authors.lastname: Lin
mesh_terms: D000222:Adaptation, Physiological; D017360:Arabidopsis / Q000502:physiology*; D001483:Base Sequence; D017931:DNA Primers; D055864:Droughts; D018384:Oxidative Stress; D018087:Plastids; D016133:Polymerase Chain Reaction; D013312:Stress, Physiological; D014867:Water
chemical_list: D017931:DNA Primers; D014867:Water