《植物生理学报》 2015, 51(1): 51-56

Ca²⁺位于H₂O₂上游参与H₂S诱导的拟南芥气孔关闭过程

李洪旺, 车永梅, 侯丽霞, 王兰香, 刘香凝, 刘新^*

青岛农业大学生命科学学院, 山东省高校植物生物技术重点实验室, 山东青岛266109

通信作者：刘；E-mail: liuxin6080@126.com；Tel: 0532-88030311

摘　要：

以拟南芥为材料, 利用药理学实验, 结合分光光度法和激光共聚焦显微技术, 研究了Ca²⁺在硫化氢(H₂S)诱导拟南芥气孔关闭过程中的作用及其与过氧化氢(H₂O₂)的关系。结果表明: H₂S诱导气孔关闭, Ca²⁺螯合剂EGTA和质膜Ca²⁺通道阻断剂硝苯地平(Nif)能不同程度抑制H₂S诱导的气孔关闭, 而内质网钙泵阻断剂毒胡萝卜素(Thaps)对H₂S的作用无显著影响。由此推测, Ca²⁺参与调节H₂S诱导的拟南芥气孔关闭过程, 且胞质中Ca²⁺来源于胞外Ca²⁺的内流。另外, H₂S诱导拟南芥叶片NADPH氧化酶基因AtRBOHD和AtRBOHF以及细胞壁过氧化物酶基因AtPRX34表达增强, 促进叶片和保卫细胞中H₂O₂积累, EGTA对此起抑制作用, 而外源CaCl2处理上调AtRBOHD、AtRBOHF和AtPRX34的表达。表明Ca²⁺可能位于H₂O₂上游参与H₂S诱导的拟南芥气孔关闭过程。

关键词：硫化氢; Ca²⁺; 过氧化氢; 气孔关闭

收稿：2014-08-13   修定：2014-12-26

资助：国家自然科学基金项目(31170237)。 致谢 山东省泰山学者团队建设工程。

Ca²⁺ Acts Upstream of H₂O₂ in Mediating H₂S -Induced Stomatal Closure in Arabidopsis thaliana

LI Hong-Wang, CHE Yong-Mei, HOU Li-Xia, WANG Lan-Xiang, LIU Xiang-Ning, LIU Xin^*

Key Laboratory of Plant Biotechnology in Universities of Shandong Province, College of Life Sciences, Qingdao Agricultural University, Qingdao, Shandong 266109, China

Corresponding author: LIU Xin; E-mail: liuxin6080@126.com; Tel: 0532-88030311

Abstract:

Using Arabidopsis thaliana as material, the effects of Ca²⁺ in hydrogen sulphide (H₂S)-induced guard cell movement and its relationship with hydrogen peroxide (H₂O₂) were investigated through pharmacological test combined with spectrophotography and confocal laser scanning microscopy techniques. The results showed that sodium hydrosulfide (NaHS), a donor of H₂S, caused stomatal closure, and this inductive effects were weakened by addition of Ca²⁺ chelator ethylene glycol-bis-(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) and plasma membrane Ca²⁺ channel blocker nifedipine (Nif), respectively, however, endoplasmic reticulum calcium pump blocker thapsigargin (Thaps) had no significant effect on stomatal movement induced by H₂S. These observations suggest that Ca²⁺ participates in H₂S-induced stomatal closure, [Ca²⁺]_cyt elevation in response to H₂S is mainly due to calcium influx across the plasma membrane. In addition, H₂S up-regulated the expression of NADPH oxidase genes AtRBOHD, AtRBOHF as well as cell wall peroxidase gene AtPRX34, prompted H₂O₂ accumulation in leaves and guard cells, while EGTA inhibited these effects of H₂S. On the other hand, exogenous CaCl2 promoted the expression of AtRBOHD, AtRBOHF and AtPRX34. Based on above results, it can be concluded that Ca²⁺ acts upstream of H₂O₂ in mediating H₂S-induced stomatal closure in A. thaliana.

Key words: H₂S; Ca²⁺; H₂O₂; stomatal closure