title: Ascorbate peroxidase from Jatropha curcas enhances salt tolerance in transgenic Arabidopsis.
abstract: Ascorbate peroxidase (APX) plays a central role in the ascorbate-glutathione cycle and is a key enzyme in cellular H2O2 me-tabolism. It includes a family of isoenzymes with different character-istics, which are identified in many higher plants. In the present study, we isolated the APX gene from Jatropha curcas L, which is similar with other previously characterized APXs as revealed by alignment and phylogenetic analysis of its deduced amino acid sequence. Real-time qPCR analysis showed that the expression level of JcAPX transcript significantly increased under NaCl stress. Subsequently, to elucidate the contribution of JcAPX to the protection against salt-induced oxi-dative stress, the expression construct p35S: JcAPX was created and transformed into Arabidopsis and transcribed. Under 150-mM NaCl stress, compared with wild type (WT), the overexpression of JcAPX in Arabidopsis increased the germination rate, the number of leaves, and the rosette area. In addition, the transgenic plants had longer roots, higher total chlorophyll content, higher total APX activity, and lower H2O2 content than the WT under NaCl stress conditions. These results suggested that higher APX activity in transgenic lines increases the salt tolerance by enhancing scavenging capacity for reactive oxygen spe-cies under NaCl stress conditions.
authors.affiliation: College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.affiliation: West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, China.
authors.forename: J
authors.initials: J
authors.lastname: Cai
authors.affiliation: Guangdong Key Laboratory of Ornamental Plant Germplasm Innovation and Utilization, Environmental Horticulture Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, China.
authors.forename: F X
authors.initials: FX
authors.lastname: Yang
authors.affiliation: College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China.
authors.forename: B
authors.initials: B
authors.lastname: Zhou
authors.affiliation: College of Architecture and Environment, Sichuan University, Chengdu, Sichuan, China zhoulr@mail.ubc.ca.
authors.forename: L R
authors.initials: LR
authors.lastname: Zhou
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D060387:Ascorbate Peroxidases / Q000235:genetics*; D002734:Chlorophyll / Q000235:genetics; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000378:metabolism; D031286:Jatropha / Q000201:enzymology; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000502:physiology; D055049:Salt Tolerance / Q000235:genetics* / Q000502:physiology; D012965:Sodium Chloride / Q000633:toxicity; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics
chemical_list: D002734:Chlorophyll; D012965:Sodium Chloride; D006861:Hydrogen Peroxide; D060387:Ascorbate Peroxidases