文献类型： 外文期刊

作者： Wei, Aili ¹ ; Xin, Xiaojing ¹ ; Wang, Yunshan ² ; Zhang, Chao ² ; Cao, Dongmei ² ;

作者机构： 1.Taiyuan Normal Univ, Dept Biol, Taiyuan 030031, Peoples R China

2.Shanxi Acad Agr Sci, Inst Hort, Taiyuan 030031, Peoples R China

关键词： SO_2;Hemerocallis fulva;Guard cell;Cell apoptosis;Signal regulation

期刊名称：ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY （ 影响因子：6.291； 五年影响因子：6.393 ）

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收录情况： SCI

摘要： Chronic and acute exposure to SO_2 is associated with increased risks of various damages to plants. In the present study, epidermal strip experiment was employed to investigate SO_2-induced guard cells apoptosis and the signal regulation in Hemerocallis fulva. The results showed that with the increase of treatment concentrate of SO_2 derivates (a mixture of sodium sulfite and sodium bisulfite, 3:1, mmol L~(-1)/ mmol L~(-1) 1.0-5.0 mmol L~(-1)), the physiological activity of the guard cells declined and cell death occurred. While the concentration of SO_2 derivatives exceeded 2.0 mmol L~(-1) the percentage of cell death increased significantly (P＜0.05). Typical features of apoptosis" including nuclear condensation, nuclear elongation, fragmentation etc. were found. Meanwhile, concomitant presence of nitric oxide (NO), reactive oxygen species (ROS) and Ca~(2+) level increment appeared. However, SO_2-induced cell death can be effectively blocked by either of the following substances with their respective optimal concentrations: antioxidant ascorbic acid (Asc; 0.05 mmol L~(-1)) or catalase (CAT; 200 UmL~(-1)), nitric oxide (NO) scavenger 2-(4-carboxyphenyl)-4, 4, 5, 5- tetramethylmidiazoline-l-oxyl-3-oxide (c-PTIO; 0.20 mmol L~(-1)), nitrate reductase inhibitor NaN_3 (0.20 mmol L~(-1)), Ca~(2+) chelating agent EGTA (0.05 mmol L~(-1)) or plasma membrane Ca~(2+) channel blocker LaCl_3 (0.05 mmol L~(-1)). In addition to a significant decrease in cell death rate, a reduction in the levels of reactive oxygen species (ROS), NO and Ca~(2+) was observed. Further study showed that compared to treatment with SO_2 alone, Asc treatment led to a decrease in NO and Ca~(2+) levels and NaN_3 treatment led to a decrease in ROS and Ca~(2+) levels, but the NO and ROS levels of the LaCl_3 treatment changed little. All results suggested that NO, ROS and Ca~(2+) were involved in the apoptosis induced by SO_2 in H. fulva. The process might be related to the burst of NO or ROS, which would activate the plasma Ca~(2+) channel and result in the increase of intercellular Ca~(2+).