title: Cryopreservation affects ROS-induced oxidative stress and antioxidant response in Arabidopsis seedlings.
abstract: Plant recovery status after cryopreservation by vitrification had a negative relationship to the oxidative stress induced by reactive oxygen species (ROS). Arabidopsis thaliana seedlings germinated for 48 h or 72 h with different survival tolerances were examined at five steps of cryopreservation, to determine the role of ROS (O2(-), H2O2 and OH) and antioxidant systems (SOD, POD, CAT, AsA and GSH) in cryo-injury. In addition, the effects of the steps on membrane lipid peroxidation were studied using malondialdehyde (MDA) as an indicator. The results indicated that H2O2-induced oxidative stress at the steps of dehydration and rapid warming was the main cause of cryo-injury of 48-h seedlings (high survival rate) and 72-h seedlings (no survival). The H2O2 was mainly generated in cotyledons, shoot tips and roots of seedlings as indicated by Amplex Red staining. Low survival of 72-h seedlings was associated with severe membrane lipid peroxidation, which was caused by increased OH generation activity and decreased SOD activity. The antioxidant-related gene expression by qRT-PCR and physiological assays suggested that the antioxidant system of 48-h seedlings were activated by ROS, and they mounted a defense against oxidative stress. A high level of ROS led to the weakening of the antioxidant system of 72-h seedlings. Correlation analysis indicated that enhanced antioxidant enzymes activities contributed to the high survival rate of 48-h seedlings, which could reflect by cryopreservation of antioxidant mutant seedlings. This model system indicated that elevated CAT activity and AsA content were determinants of cryogenic stress tolerance, whose manipulation could improve the recovery of seedlings after cryopreservation.
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800, Rd. Dong Chuan, Shanghai 200240, PR China. Electronic address: chengq0111@gmail.com.
authors.forename: Guan-Qun
authors.initials: GQ
authors.lastname: Chen
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800, Rd. Dong Chuan, Shanghai 200240, PR China. Electronic address: renliaqx@gmail.com.
authors.forename: Li
authors.initials: L
authors.lastname: Ren
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800, Rd. Dong Chuan, Shanghai 200240, PR China. Electronic address: zjjsnake@sina.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: United States Department of Agriculture-Agricultural Research Service, National Clonal Germplasm Repository, 33447 Peoria Road, Corvallis, OR 97333-2521, USA. Electronic address: Barbara.Reed@ars.usda.gov.
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Reed
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800, Rd. Dong Chuan, Shanghai 200240, PR China. Electronic address: zhangdi2013@sjtu.edu.cn.
authors.forename: Di
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology, Shanghai Jiao Tong University, No. 800, Rd. Dong Chuan, Shanghai 200240, PR China. Electronic address: shenxh62@sjtu.edu.cn.
authors.forename: Xiao-Hui
authors.initials: XH
authors.lastname: Shen
mesh_terms: D017360:Arabidopsis / Q000502:physiology*; D002374:Catalase / Q000378:metabolism; D002462:Cell Membrane / Q000473:pathology; D018548:Cotyledon / Q000378:metabolism; D015925:Cryopreservation; D006358:Hot Temperature; D006861:Hydrogen Peroxide / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress / Q000502:physiology*; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D036226:Seedlings / Q000502:physiology; D013482:Superoxide Dismutase / Q000378:metabolism; D058989:Vitrification
chemical_list: D017382:Reactive Oxygen Species; D008315:Malondialdehyde; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase
keywords: Antioxidant systems; Arabidopsis seedlings; Oxidative stress response; ROS; Vitrification-based cryopreservation