title: Insight into mechanism of lanthanum (III) induced damage to plant photosynthesis.
abstract: A great deal of literature is available regarding the environmental and ecological effects of rare earth element pollution on plants. These studies have shown that excess lanthanum (La) (III) in the environment can inhibit plant growth and even cause plant death. Moreover, inhibition of plant photosynthesis is known to be one of the physiological bases of these damages. However, the mechanism responsible for these effects is still unclear. In this study, the mechanism of La(III)-induced damage to plant photosynthesis was clarified from the viewpoint of the chloroplast ultrastructure, the contents of chloroplast mineral elements and chlorophyll, the transcription of chloroplast ATPase subunits and chloroplast Mg(2+)-ATPase activity, in which rice was selected as a study object. Following treatment with low level of La(III), the chloroplast ultrastructure of rice was not changed, and the contents of chloroplast mineral elements (Mg, P, K, Ca, Mn, Fe, Ni, Cu, and Zn) increased, but the chlorophyll content did not change significantly. Moreover, the transcription of chloroplast ATPase subunits, chloroplast Mg(2+)-ATPase activity, the net photosynthetic rate and growth indices increased. Following treatment with high levels of La(III), the chloroplast ultrastructure was damaged, chloroplast mineral elements (except Cu and Zn) and chlorophyll contents decreased, and the transcription of chloroplast ATPase subunits, chloroplast Mg(2+)-ATPase activity, the net photosynthetic rate and growth indices decreased. Based on these results, a possible mechanism of La(III)-induced damage to plant photosynthesis was proposed to provide a reference for scientific evaluation of the potential ecological risk of rare earth elements in the environment.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangsu Coorperative Innovation Center of Water Treatment Technology and Materials, College of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China.
authors.forename: Huiqing
authors.initials: H
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangsu Coorperative Innovation Center of Water Treatment Technology and Materials, College of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China.
authors.forename: Lihong
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangsu Coorperative Innovation Center of Water Treatment Technology and Materials, College of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China.
authors.forename: Yueli
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangsu Coorperative Innovation Center of Water Treatment Technology and Materials, College of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China.
authors.forename: Jingwen
authors.initials: J
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangsu Coorperative Innovation Center of Water Treatment Technology and Materials, College of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China. Electronic address: qingzhou510@yahoo.com.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Jiangsu Collaborative Innovation Center of Biomedical Functional Materials, Jiangsu Key Laboratory of Biomedical Materials, College of Chemistry and Materials Science, Nanjing Normal University, Nanjing 210046, China; School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China. Electronic address: huangxiaohuanjnu@yahoo.com.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Huang
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D002736:Chloroplasts / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D007811:Lanthanum / Q000633:toxicity*; D046529:Microscopy, Electron, Transmission; D012275:Oryza / Q000187:drug effects / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects*; D012989:Soil Pollutants / Q000633:toxicity*
chemical_list: D012989:Soil Pollutants; D002734:Chlorophyll; D007811:Lanthanum; D000251:Adenosine Triphosphatases
keywords: Chloroplast mineral elements; Chloroplast ultrastructure; Lanthanum pollution; Mg(2+)–ATPase activity; Rice photosynthesis