title: Cadmium-induced genomic instability in Arabidopsis: Molecular toxicological biomarkers for early diagnosis of cadmium stress.
abstract: Microsatellite instability (MSI) analysis, random-amplified polymorphic DNA (RAPD), and methylation-sensitive arbitrarily primed PCR (MSAP-PCR) are methods to evaluate the toxicity of environmental pollutants in stress-treated plants and human cancer cells. Here, we evaluate these techniques to screen for genetic and epigenetic alterations of Arabidopsis plantlets exposed to 0-5.0 mg L(-1) cadmium (Cd) for 15 d. There was a substantial increase in RAPD polymorphism of 24.5, and in genomic methylation polymorphism of 30.5-34.5 at CpG and of 14.5-20 at CHG sites under Cd stress of 5.0 mg L(-1) by RAPD and of 0.25-5.0 mg L(-1) by MSAP-PCR, respectively. However, only a tiny increase of 1.5 loci by RAPD occurred under Cd stress of 4.0 mg L(-1), and an additional high dose (8.0 mg L(-1)) resulted in one repeat by MSI analysis. MSAP-PCR detected the most significant epigenetic modifications in plantlets exposed to Cd stress, and the patterns of hypermethylation and polymorphisms were consistent with inverted U-shaped dose responses. The presence of genomic methylation polymorphism in Cd-treated seedlings, prior to the onset of RAPD polymorphism, MSI and obvious growth effects, suggests that these altered DNA methylation loci are the most sensitive biomarkers for early diagnosis and risk assessment of genotoxic effects of Cd pollution in ecotoxicology.
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China; Department of Basic Medicine, He University, Shenyang 110163, PR China.
authors.forename: Hetong
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China; Environmental Science College, Liao University, Shenyang 110036, PR China.
authors.forename: Lei
authors.initials: L
authors.lastname: He
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China; Environmental Science College, Liao University, Shenyang 110036, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Song
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China; Shanghai Institute of Technology, Shanghai 201418, PR China.
authors.forename: Weina
authors.initials: W
authors.lastname: Cui
authors.affiliation: Life Science Department, Luoyang Normal University, Luoyang 471022, PR China.
authors.forename: Yanzhao
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China.
authors.forename: Chunyun
authors.initials: C
authors.lastname: Jia
authors.affiliation: Key Laboratory of Eco-restoration, Shenyang University, Shenyang 11044, PR China.
authors.forename: Dennis
authors.initials: D
authors.lastname: Francis
authors.affiliation: Cardiff University, School of Biosciences, Cardiff CF10 33TL, UK.
authors.forename: Hilary J
authors.initials: HJ
authors.lastname: Rogers
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China.
authors.forename: Lizong
authors.initials: L
authors.lastname: Sun
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China.
authors.forename: Peidong
authors.initials: P
authors.lastname: Tai
authors.affiliation: Shanghai Institute of Technology, Shanghai 201418, PR China.
authors.forename: Xiujuan
authors.initials: X
authors.lastname: Hui
authors.affiliation: Key Laboratory of Eco-restoration, Shenyang University, Shenyang 11044, PR China.
authors.forename: Yuesuo
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, PR China. Electronic address: liuwan63@hotmail.com.
authors.forename: Wan
authors.initials: W
authors.lastname: Liu
mesh_terms: D017360:Arabidopsis / Q000187:drug effects* / Q000235:genetics; D015415:Biomarkers / Q000032:analysis; D002104:Cadmium / Q000633:toxicity*; D004249:DNA Damage; D019175:DNA Methylation / Q000187:drug effects*; D054750:Ecotoxicology / Q000379:methods*; D004785:Environmental Pollutants / Q000633:toxicity*; D053842:Microsatellite Instability / Q000187:drug effects*; D011110:Polymorphism, Genetic / Q000187:drug effects; D019105:Random Amplified Polymorphic DNA Technique; D036226:Seedlings / Q000187:drug effects / Q000235:genetics
chemical_list: D015415:Biomarkers; D004785:Environmental Pollutants; D002104:Cadmium
keywords: Arabidopsis thaliana; Cadmium; Methylation-sensitive arbitrarily primed PCR; Microsatellite instability; Random-amplified polymorphic DNA