Similar stress responses are elicited by copper and ultraviolet radiation in the aquatic plant Lemna gibba:: Implication of reactive oxygen species as common signals

被引:149
作者
Babu, TS [1 ]
Akhtar, TA [1 ]
Lampi, MA [1 ]
Tripuranthakam, S [1 ]
Dixon, DG [1 ]
Greenberg, BM [1 ]
机构
[1] Univ Waterloo, Dept Biol, Waterloo, ON N2L 3G1, Canada
关键词
chalcone synthase; flavonoids; glutathione reductase; oxidative stress; reactive oxygen species; superoxide dismutase;
D O I
10.1093/pcp/pcg160
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
Metals and ultraviolet (UV) radiation are two environmental stressors that can cause damage to plants. These two types of stressors often impact simultaneously on plants and both are known to promote reactive oxygen species (ROS) production. However, little information is available on the potential parallel stress responses elicited by metals and UV radiation. Using the aquatic plant Lemna gibba, we found that copper and simulated solar radiation (SSR, a light source containing photosynthetically active radiation (PAR) and UV radiation) induced similar responses in the plants. Both copper and SSR caused ROS formation. The ROS levels were higher when copper was combined with SSR than when applied with PAR. Higher concentrations of copper plus PAR caused toxicity as monitored by diminished growth and chlorophyll content. This toxicity was more pronounced when copper was combined with SSR. Because the generation of ROS was also higher when copper was combined with SSR, we attributed this enhanced toxicity to elevated levels of ROS. In comparison to PAR-grown plants, SSR treated plants exhibited elevated levels of superoxide dismutase (SOD) and glutathione reductase (GR). These enzyme levels were further elevated under both PAR and SSR when copper was added at concentrations that generated ROS. Interestingly, copper treatment in the absence of SSR (i.e. copper plus PAR) induced synthesis of the same flavonoids as those observed in SSR without copper. Finally, addition of either dimethyl thiourea or GSH (two common ROS scavengers) lowered in vivo ROS production, alleviated toxicity and diminished induction of GR as well as accumulation of UV absorbing compounds. Thus, the potential of ROS being a common signal for acclimation to stress by both copper and UV can be considered.
引用
收藏
页码:1320 / 1329
页数:10
相关论文
共 83 条
[1]   Two distinct sources of elicited reactive oxygen species in tobacco epidermal cells [J].
Allan, AC ;
Fluhr, R .
PLANT CELL, 1997, 9 (09) :1559-1572
[2]   Use of transgenic plants to study antioxidant defenses [J].
Allen, RD ;
Webb, RP ;
Schake, SA .
FREE RADICAL BIOLOGY AND MEDICINE, 1997, 23 (03) :473-479
[3]   Role of superoxide dismutases (SODs) in controlling oxidative stress in plants [J].
Alscher, RG ;
Erturk, N ;
Heath, LS .
JOURNAL OF EXPERIMENTAL BOTANY, 2002, 53 (372) :1331-1341
[4]   OXYGEN FREE-RADICALS AND HUMAN-DISEASES [J].
ARUOMA, OI ;
KAUR, H ;
HALLIWELL, B .
JOURNAL OF THE ROYAL SOCIETY OF HEALTH, 1991, 111 (05) :172-177
[5]   The water-water cycle in chloroplasts: Scavenging of active oxygens and dissipation of excess photons [J].
Asada, K .
ANNUAL REVIEW OF PLANT PHYSIOLOGY AND PLANT MOLECULAR BIOLOGY, 1999, 50 :601-639
[6]  
AUST S D, 1985, Journal of Free Radicals in Biology and Medicine, V1, P3, DOI 10.1016/0748-5514(85)90025-X
[7]  
Babu TS, 1999, PHOTOCHEM PHOTOBIOL, V69, P553, DOI 10.1562/0031-8655(1999)069<0553
[8]   Synergistic effects of a photooxidized polycyclic aromatic hydrocarbon and copper on photosynthesis and plant growth: Evidence that in vivo formation of reactive oxygen species is a mechanism of copper toxicity [J].
Babu, TS ;
Marder, JB ;
Tripuranthakam, S ;
Dixon, DG ;
Greenberg, BM .
ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 2001, 20 (06) :1351-1358
[9]  
Beauchamp C., 1971, ANAL BIOCHEM, V44, P276, DOI DOI 10.1016/0003-2697(71)90370-8
[10]   HYDROGEN-PEROXIDE MEDIATES AMYLOID-BETA PROTEIN TOXICITY [J].
BEHL, C ;
DAVIS, JB ;
LESLEY, R ;
SCHUBERT, D .
CELL, 1994, 77 (06) :817-827