title: Cd-induced changes in leaf proteome of the hyperaccumulator plant Phytolacca americana.
abstract: Cadmium (Cd) is highly toxic to all organisms. Soil contamination by Cd has become an increasing problem worldwide due to the intensive use of Cd-containing phosphate fertilizers and industrial zinc mining. Phytolacca americana L. is a Cd hyperaccumulator plant that can grow in Cd-polluted areas. However, the molecular basis for its remarkable Cd resistance is not known. In this study, the effects of Cd exposure on protein expression patterns in P.americana was investigated by 2-dimensional gel electrophoresis (2-DE). 2-DE profiles of leaf proteins from both control and Cd-treated (400μM, 48h) seedlings were compared quantitatively using ImageMaster software. In total, 32 differentially expressed protein spots were identified using MALDI-TOF/TOF mass spectrometry coupled to protein database search, corresponding to 25 unique gene products. Of those 14 were enhanced/induced while 11 reduced under Cd treatment. The alteration pattern of protein expression was verified for several key proteins involved in distinct metabolic pathways by immuno-blot analysis. Major changes were found for the proteins involved in photosynthetic pathways as well as in the sulfur- and GSH-related metabolisms. One-third of the up-regulated proteins were attributed to transcription, translation and molecular chaperones including a protein belonging to the calreticulin family. Other proteins include antioxidative enzymes such as 2-cys-peroxidase and oxidoreductases. The results of this proteomic analysis provide the first and primary information regarding the molecular basis of Cd hypertolerance in P. americana.
authors: Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors: Le
authors: L
authors: Zhao
authors: Yong-Le
authors: YL
authors: Sun
authors: Su-Xia
authors: SX
authors: Cui
authors: Mei
authors: M
authors: Chen
authors: Hao-Meng
authors: HM
authors: Yang
authors: Hui-Min
authors: HM
authors: Liu
authors: Tuan-Yao
authors: TY
authors: Chai
authors: Fang
authors: F
authors: Huang
mesh_terms: D002104:Cadmium / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant; D029604:Phytolacca americana / Q000235:genetics* / Q000378:metabolism; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D020543:Proteome / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000235:genetics / Q000378:metabolism; D012989:Soil Pollutants / Q000378:metabolism*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D010940:Plant Proteins; D020543:Proteome; D012989:Soil Pollutants; D002104:Cadmium