钙离子参与拟南芥的缺氧信号传导

报告了钙流通抑制剂钌红对缺氧条件下拟南芥中ADH基因表达的诱导和植株存活的影响。结果表明 ,缺氧早期ADH基因的激活和表达需要钙离子 ,钌红处理可以延长缺氧条件下拟南芥植株的存活期。据此推测 :拟南芥中缺氧诱导的细胞死亡是一个钙离子介导的主动过程 ,钌红通过阻止细胞内钙离子浓度的增加而抑制这一过程。延长缺氧处理的时间会导致拟南芥叶片细胞内发生核凝聚和染色体断裂的现象 ,也进一步验证了这种构想。表明缺氧处理引起的叶片细胞损伤直至植株死亡是一个程序化的过程

Involvement of Calcium in the Anoxia-Signaling Pathway of Arabidopsis thaliana

We report here the effects of Ruthenium Red, an organellar Ca 2 flux inhibitor, on the induction of the expression of ADH gene and the survival of Arabidopsis plants during anoxia. Our results suggest that Ca 2 is required for the activation of the ADH gene in an early stage of anoxia. In addition, our data show that the presence of Ruthenium Red, which can prolong the survival time of Arabidopsis under anoxia. We propose that the anoxia induced cell death in Arabidopsis may be an active process, and that this process requires an increase in intracellular Ca 2 , which can be blocked by Ruthenium Red. Consistent with this idea, we found that nuclear condensation and chromosomal fragmentation occurred in leaf cells of Arabidopsis plants under prolonged anoxia. From the characteristics of the cell damage in leaves subjected to anoxia, it appears that apoptosis occurs first, which is followed by the death of the whole Arabidopsis plants.