Comparative proteomic analysis of the short-term responses of rice roots and leaves to cadmium.
Cadmium (Cd) is a non-essential heavy metal that is recognized as a major environmental pollutant. While Cd responses and toxicities in some plant species have been well established, there are few reports about the effects of short-term exposure to Cd on rice, a model monocotyledonous plant, at the proteome level. To investigate the effect of Cd in rice, we monitored the influence of Cd exposure on root and leaf proteomes. After Cd treatment, root and leaf tissues were separately collected and leaf proteins were fractionated with polyethylene glycol. Differentially regulated proteins were selected after image analysis and identified using MALDI-TOF MS. A total of 36 proteins were up- or down-regulated following Cd treatment. As expected, total glutathione levels were significantly decreased in Cd-treated roots, and approximately half of the up-regulated proteins in roots were involved in responses to oxidative stress. These results suggested that prompt antioxidative responses might be necessary for the reduction of Cd-induced oxidative stress in roots but not in leaves. In addition, RNA gel blot analysis showed that the proteins identified in the proteomic analysis were also differentially regulated at the transcriptional level. Collectively, our study provides insights into the integrated molecular mechanisms of early responses to Cd in rice.
Lee
Kyunghee
K
Division of Applied Life Science (BK21 Program), Plant Molecular Biology and Biotechnology Research Center, Gyeongsang National University, Jinju 660-701, Republic of Korea.
Bae
Dong Won
DW
Kim
Sun Ho
SH
Han
Hay Ju
HJ
Liu
Xiaomin
X
Park
Hyeong Cheol
HC
Lim
Chae Oh
CO
Lee
Sang Yeol
SY
Chung
Woo Sik
WS
D000596:Amino Acids / Q000378:metabolism; D000975:Antioxidants / Q000378:metabolism; D002104:Cadmium / Q000378:metabolism*; D050260:Carbohydrate Metabolism; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D005978:Glutathione / Q000378:metabolism; D012275:Oryza / Q000378:metabolism*; D018384:Oxidative Stress; D010788:Photosynthesis; D018515:Plant Leaves / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism*; D040901:Proteomics; D018749:RNA, Plant / Q000378:metabolism
D000596:Amino Acids; D000975:Antioxidants; D018749:RNA, Plant; D002104:Cadmium; D005978:Glutathione