title: SELDI-TOF MS-based discovery of a biomarker in Cucumis sativus seeds exposed to CuO nanoparticles.
abstract: Metal oxide nanoparticles (NPs) can inhibit plant seed germination and root elongation via the release of metal ions. In the present study, two acute phytotoxicity tests, seed germination and root elongation tests, were conducted on cucumber seeds (Cucumis sativus) treated with bulk copper oxide (CuO) and CuO NPs. Two concentrations of bulk CuO and CuO NPs, 200 and 600ppm, were used to test the inhibition rate of root germination; both concentrations of bulk CuO weakly inhibited seed germination, whereas CuO NPs significantly inhibited germination, showing a low germination rate of 23.3% at 600ppm. Root elongation tests demonstrated that CuO NPs were much stronger inhibitors than bulk CuO. SELDI-TOF MS analysis showed that 34 proteins were differentially expressed in cucumber seeds after exposure to CuO NPs, with the expression patterns of at least 9 proteins highly differing from those in seeds treated with bulk CuO and in control plants. Therefore, these 9 proteins were used to identify CuO NP-specific biomarkers in cucumber plants exposed to CuO NPs. A 5977-m/z protein was the most distinguishable biomarker for determining phytotoxicity by CuO NPs. Principal component analysis (PCA) of the SELDI-TOF MS results showed variability in the modes of inhibitory action on cucumber seeds and roots. To our knowledge, this is the first study to demonstrate that the phytotoxic effect of metal oxide NPs on plants is not caused by the same mode of action as other toxins.
authors.affiliation: School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: Young-Sun
authors.initials: YS
authors.lastname: Moon
authors.affiliation: School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Republic of Korea.
authors.forename: Eun-Sil
authors.initials: ES
authors.lastname: Park
authors.affiliation: Department of Environmental Engineering, Kumoh National Institute of Technology, Daehak-ro 61, Gumi, Gyeongbuk 730-701, Republic of Korea.
authors.forename: Tae-Oh
authors.initials: TO
authors.lastname: Kim
authors.affiliation: Department of Bioenvironmental Chemistry and Institute of Agricultural Science and Technology, Chonbuk National University, Jeonju 561-756, Republic of Korea.
authors.forename: Hoi-Seon
authors.initials: HS
authors.lastname: Lee
authors.affiliation: School of Applied Biosciences, Kyungpook National University, Daegu 702-701, Republic of Korea. Electronic address: selpest@knu.ac.kr.
authors.forename: Sung-Eun
authors.initials: SE
authors.lastname: Lee
mesh_terms: D015415:Biomarkers / Q000378:metabolism*; D003300:Copper / Q000633:toxicity*; D018553:Cucumis sativus / Q000187:drug effects / Q000196:embryology* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects; D053768:Metal Nanoparticles / Q000737:chemistry / Q000633:toxicity*; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects; D012639:Seeds / Q000187:drug effects* / Q000254:growth & development; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D018675:Toxicity Tests / Q000379:methods
chemical_list: D015415:Biomarkers; D010940:Plant Proteins; D003300:Copper; C030973:cupric oxide
keywords: Biomarker; CuO nanoparticles; Phytotoxicity; SELDI-TOF MS