title: Endogenous salicylic acid is required for promoting cadmium tolerance of Arabidopsis by modulating glutathione metabolisms.
abstract: A few studies with NahG transgenic lines of Arabidopsis show that depletion of SA enhances cadmium (Cd) tolerance. However, it remains some uncertainties that the defence signaling may be a result of catechol accumulation in NahG transgenic lines but not SA deficiency. Here, we conducted a set of hydroponic assays with another SA-deficient mutant sid2 to examine the endogenous roles of SA in Cd tolerance, especially focusing on the glutathione (GSH) cycling. Our results showed that reduced SA resulted in negative effects on Cd tolerance, including decreased Fe uptake and chlorophyll concentration, aggravation of oxidative damage and growth inhibition. Cd exposure significantly increased SA concentration in wild-type leaves, but did not affect it in sid2 mutants. Depletion of SA did not disturb the Cd uptake in either roots or shoots. The reduced Cd tolerance in sid2 mutants is due to the lowered GSH status, which is associated with the decreased expression of serine acetyltransferase along with a decline in contents of non-protein thiols, phytochelatins, and the lowered transcription and activities of glutathione reductase1 (GR1) which reduced GSH regeneration. Finally, the possible mode of SA signaling through the GR/GSH pathway during Cd exposure is discussed.
authors.affiliation: Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences; Geological Research Center For Agricultural Applications, China Geological Survey, Hangzhou, China. Electronic address: ndgb@163.com.
authors.forename: Bin
authors.initials: B
authors.lastname: Guo
authors.affiliation: Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences; Geological Research Center For Agricultural Applications, China Geological Survey, Hangzhou, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Liu
authors.affiliation: Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences; Geological Research Center For Agricultural Applications, China Geological Survey, Hangzhou, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Li
authors.affiliation: Institute of Virology and Biotechnology, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
authors.forename: Keke
authors.initials: K
authors.lastname: Yi
authors.affiliation: Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences; Geological Research Center For Agricultural Applications, China Geological Survey, Hangzhou, China.
authors.forename: Nengfei
authors.initials: N
authors.lastname: Ding
authors.affiliation: Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences; Geological Research Center For Agricultural Applications, China Geological Survey, Hangzhou, China.
authors.forename: Ningyu
authors.initials: N
authors.lastname: Li
authors.affiliation: Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences; Geological Research Center For Agricultural Applications, China Geological Survey, Hangzhou, China.
authors.forename: Yicheng
authors.initials: Y
authors.lastname: Lin
authors.affiliation: Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences; Geological Research Center For Agricultural Applications, China Geological Survey, Hangzhou, China. Electronic address: fuql161@yahoo.com.cn.
authors.forename: Qinglin
authors.initials: Q
authors.lastname: Fu
mesh_terms: D000975:Antioxidants / Q000737:chemistry; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D002104:Cadmium / Q000737:chemistry*; D002396:Catechols / Q000737:chemistry; D005978:Glutathione / Q000378:metabolism*; D018527:Hydroponics; D009154:Mutation; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D054811:Phytochelatins / Q000378:metabolism; D018515:Plant Leaves / Q000187:drug effects; D018517:Plant Roots / Q000187:drug effects; D018520:Plant Shoots / Q000187:drug effects; D020156:Salicylic Acid / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D002396:Catechols; D002104:Cadmium; D054811:Phytochelatins; D005978:Glutathione; C034221:catechol; D020156:Salicylic Acid
keywords: Antioxidant enzymes; Cadmium; Element uptake; GSH; Salicylic acid