Zn^(2+)对高盐和紫外线胁迫条件下水稻根尖细胞程序性死亡的影响

Effects of Zn^(2+) on rice root tip cells programmed cell death under high salt stress or UV-induced

前期研究表明:500mmol.L-1NaCl处理能诱导水稻武运粳8号根尖细胞发生细胞程序性死亡(programmed celldeath,PCD)。为了研究Zn2+对盐胁迫诱导的水稻根尖细胞PCD的影响,采用不同浓度Zn2+进行试验,结果表明:10μmol.L-1Zn2+能够在一定程度上缓解PCD现象。对这一过程中抗氧化酶(CAT、APX、POD和SOD)活性进行检测,发现抗氧化酶活性短期迅速升高,随后降低,10μmol.L-1Zn2+试验组的抗氧化酶活性高于对照组与单独NaCl处理组。而对H2O2在根尖细胞积累的观测结果显示Zn2+的添加能减少H2O2的积累,证明低水平Zn2+(10μmol.L-1)能够诱导抗氧化酶活性上升,并抑制活性氧产生。Zn2+同样可以缓解紫外线诱导的水稻根尖细胞原生质体PCD,而添加特异性的锌离子螯合剂TPEN(NNN′,N′-tetrakis-(2-pyridylmethyl)ethylenediamine)则会促进PCD的发生。据此推测:一定水平Zn2+对不同胁迫模式下发生的PCD进程的缓解作用具有普遍性。

Previous study indicated that,the root tip cells of Oryza sativa L.Wuyunjing 8 could be induced to programmed cell death(PCD)by 500 mmol·L-1 NaCl treatment.To investigate the effects of Zn2+ on the PCD of rice root tip cells which was induced by salt stress,tested cells were added with Zn2+ solutions of different concentrations.The results showed that 10 μmol·L-1 Zn2+ could partially inhibit the PCD.The activity of antioxidant enzymes(CAT,APX,POD and SOD)increased rapidly,and then decreased during salt-indu...