title: Diuron treatment reveals the different roles of two cyclic electron transfer pathways in photosystem II in Arabidopsis thaliana.
abstract: Three ecotypes of Arabidopsis thaliana, ecotype Columbia (Wild type, Wt) and two mutants (pgr5 and ndf4), were used to evaluate the effects of diuron on photosynthetic activity of A. thaliana. It was found that diuron adversely affected the fresh weight and chlorophyll content of the plants. Chlorophyll fluorescence studies determined that the pgr5 mutant was more sensitive to diuron than Wt and the ndf4 mutant. Gene expression analysis revealed different roles for the two cyclic electron transfer (CET) pathways, NAD(P)H dehydrogenase (NDH) and proton gradient regulation (PGR5) pathways, in the plant after diuron treatment. For example, a gene in the NDH pathway, lhca5, was activated in the low dose (LD) group in the pgr5 mutant, but was down-regulated in the moderate dose (MD) group, along with two other NDH-related genes (ppl2 and ndhH). In the PGR5 pathway, the pgr5 gene was functional under conditions of increased stress (MD group), and was up-regulated to a greater extent in the ndf4 mutant than that in the Wt and pgr5 mutant. Our results suggest that the PGR5 pathway in plants is more important than the NDH pathway during resistance to environmental stress. Deficiencies in the PGR5 pathway could not be counteracted by the NDH pathway, but deficiencies in the NDH pathway could be overcome by stimulating PGR5.
authors.affiliation: College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, PR China.
authors.forename: Yujian
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Department of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310032, PR China.
authors.forename: Si
authors.initials: S
authors.lastname: Chen
authors.affiliation: College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou 310032, PR China.
authors.forename: Xiaoji
authors.initials: X
authors.lastname: Fan
authors.affiliation: Department of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310032, PR China.
authors.forename: Hao
authors.initials: H
authors.lastname: Song
authors.affiliation: Department of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310032, PR China.
authors.forename: Xingxing
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Food Science and Technology, Zhejiang University of Technology, Hangzhou 310032, PR China.
authors.forename: Jiahui
authors.initials: J
authors.lastname: Xu
authors.affiliation: College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China; Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Chinese Academy of Sciences, Urumqi 830011, PR China. Electronic address: hfqian@zjut.edu.cn.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Qian
mesh_terms: D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics* / Q000502:physiology; D029681:Arabidopsis Proteins / Q000235:genetics*; D004237:Diuron / Q000633:toxicity*; D004579:Electron Transport / Q000187:drug effects* / Q000235:genetics; D006540:Herbicides / Q000633:toxicity*; D009154:Mutation; D010788:Photosynthesis / Q000187:drug effects* / Q000235:genetics; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D006540:Herbicides; C465062:PGR5 protein, Arabidopsis; D045322:Photosynthetic Reaction Center Complex Proteins; D004237:Diuron
keywords: Cyclic electron transfer; Diuron; Photosynthesis; ndf4; pgr5