Relationship Between Proline and Hg2+-Induced Oxidative Stress in a Tolerant Rice Mutant

  • Feijuan Wang
  • Bin Zeng
  • Zongxiu Sun
  • Cheng ZhuEmail author


There has been little agreement regarding the mechanism by which proline reduces heavy metal stress. The present work examines the relationship between Hg2+-induced oxidative stress and proline accumulation in rice and explores the possible mechanisms through which proline protects against Hg2+ stress. The effect of proline on alleviation of Hg2+ toxicity was studied by spectrophotography and enzymatic methods. Hg2+ induced oxidative stress in rice by increasing lipid peroxidation. Pretreatment of the rice with 2 mM proline for 12 h profoundly alleviated Hg2+-induced lipid peroxidation and minimized H2O2 accumulation. Proline pretreatment significantly reduced (p < 0.01) the Hg2+ content in rice leaves. A comparison of the effects of proline pretreatment on H2O2 accumulation by Hg2+ and aminotrazole suggested that proline protected cells from Hg2+-induced oxidative stress by scavenging reactive oxygen species. The present work demonstrates a protective effect of proline on Hg2+ toxicity through detoxifying reactive oxygen species, rather than chelating metal ions or maintaining the water balance under Hg2+ stress.


Heavy Metal Proline Rice Seedling Proline Content H2O2 Content 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.







Oxidative glutathione




Reactive oxygen species


2-Thiobarbituric acid



This work was supported by the National Key Technologies R&D Program of China during the 11th Five-Year Plan Period (NO. 2006BAK02A18), the Natural Science Foundation of Zhejiang Province (NO. Z306300), and the National Key Basic Research and Development Program (NO. 2002CB410804).


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Feijuan Wang
    • 1
  • Bin Zeng
    • 1
  • Zongxiu Sun
    • 2
  • Cheng Zhu
    • 1
    Email author
  1. 1.State Key Laboratory of Plant Physiology & Biochemistry, College of Life SciencesZhejiang UniversityHangzhouChina
  2. 2.State Key Laboratory of Rice BiologyChina National Rice Research InstituteHangzhouChina

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