title: Cobalt alleviates GA-induced programmed cell death in wheat aleurone layers via the regulation of H2O2 production and heme oxygenase-1 expression.
abstract: Heme oxygenase-1 (HO-1) and hydrogen peroxide (H2O2) are key signaling molecules that are produced in response to various environmental stimuli. Here, we demonstrate that cobalt is able to delay gibberellic acid (GA)-induced programmed cell death (PCD) in wheat aleurone layers. A similar response was observed when samples were pretreated with carbon monoxide (CO) or bilirubin (BR), two end-products of HO catalysis. We further observed that increased HO-1 expression played a role in the cobalt-induced alleviation of PCD. The application of HO-1-specific inhibitor, zinc protoporphyrin-IX (ZnPPIX), substantially prevented the increases of HO-1 activity and the alleviation of PCD triggered by cobalt. The stimulation of HO-1 expression, and alleviation of PCD might be caused by the initial H2O2 production induced by cobalt. qRT-PCR and enzymatic assays revealed that cobalt-induced gene expression and the corresponding activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), three enzymes that metabolize reactive oxygen species, were consistent with the H2O2 accumulation during GA treatment. These cobalt responses were differentially blocked by co-treatment with ZnPPIX. We therefore suggest that HO-1 functions in the cobalt-triggered alleviation of PCD in wheat aleurone layers, which is also dependent on the enhancement of the activities of antioxidant enzymes.
authors.affiliation: College of Life Sciences, Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China. mingzhuwus@126.com.
authors.forename: Mingzhu
authors.initials: M
authors.lastname: Wu
authors.affiliation: College of Life Sciences, Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China. 2012816150@njau.edu.cn.
authors.forename: Jiale
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Life Sciences, Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China. qiezi324@163.com.
authors.forename: Fangquan
authors.initials: F
authors.lastname: Wang
authors.affiliation: China Tobacco Gene Research Center, Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China. likite2002@163.com.
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.affiliation: China Tobacco Gene Research Center, Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China. yangjun@ztri.com.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Yang
authors.affiliation: College of Life Sciences, Laboratory Center of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China. wbshenh@njau.edu.cn.
authors.forename: Wenbiao
authors.initials: W
authors.lastname: Shen
mesh_terms: D017209:Apoptosis; D003035:Cobalt / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D005875:Gibberellins / Q000378:metabolism*; D051547:Heme Oxygenase-1 / Q000235:genetics* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D014908:Triticum / Q000235:genetics / Q000378:metabolism*; D015854:Up-Regulation; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D005875:Gibberellins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D003035:Cobalt; D006861:Hydrogen Peroxide; C007842:gibberellic acid; D051547:Heme Oxygenase-1; D000516:alpha-Amylases