Simultaneous expression of choline oxidase, superoxide dismutase and ascorbate peroxidase in potato plant chloroplasts provides synergistically enhanced protection against various abiotic stresses.
Plants synthesize compatible solutes such as glycinebetaine (GB) in response to abiotic stresses. To evaluate the synergistic and protective effect of GB, transgenic potato plants expressing superoxide dismutase (SOD) and ascorbate peroxidase (APX) targeting to chloroplasts (referred to as SSA plants) were retransformed with a bacterial choline oxidase (codA) gene to synthesize GB in chloroplast in naturally occurring non-accumulator potato plants (including SSA) under the control of the stress-inducible SWPA2 promoter (referred to as SSAC plants). GB accumulation resulted in enhanced protection of these SSAC plants and lower levels of H(2)O(2) compared with SSA and non-transgenic (NT) plants after methyl viologen (MV)-mediated oxidative stress. Additionally, SSAC plants demonstrated synergistically enhanced tolerance to salt and drought stresses at the whole-plant level. GB accumulation in SSAC plants helped to maintain higher activities of SOD, APX and catalase following oxidative, salt and drought stress treatments than is observed in SSA and NT plants. Conclusively, GB accumulation in SSAC plants along with overexpression of antioxidant genes rendered the plants tolerant to multiple environmental stresses in a synergistic fashion.
Ahmad
Raza
R
Environmental Biotechnology Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-806, Korea.
Kim
Yun-Hee
YH
Kim
Myoung-Duck
MD
Kwon
Suk-Yoon
SY
Cho
Kwangsoo
K
Lee
Haeng-Soon
HS
Kwak
Sang-Soo
SS
D000222:Adaptation, Physiological / Q000187:drug effects; D000429:Alcohol Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D060387:Ascorbate Peroxidases; D001622:Betaine / Q000378:metabolism; D015153:Blotting, Western; D002736:Chloroplasts / Q000201:enzymology* / Q000235:genetics; D055864:Droughts; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D018384:Oxidative Stress; D010269:Paraquat / Q000494:pharmacology; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012965:Sodium Chloride / Q000494:pharmacology; D011198:Solanum tuberosum / Q000201:enzymology* / Q000235:genetics; D013482:Superoxide Dismutase / Q000235:genetics / Q000378:metabolism*; D014867:Water / Q000494:pharmacology
D014867:Water; D001622:Betaine; D012965:Sodium Chloride; D000429:Alcohol Oxidoreductases; C019888:choline oxidase; D010544:Peroxidases; D060387:Ascorbate Peroxidases; D013482:Superoxide Dismutase; D010269:Paraquat