一氧化氮对植物重金属胁迫抗性的影响研究进展  

Advances on effects of nitric oxide on resistances of plants to heavy metal stress

作　　者：夏海威 施国新[1] 黄敏[1] 吴娟[1] 

机构地区：[1]南京师范大学生命科学学院江苏省生物多样性与生物技术重点实验室,南京210023

出　　处：《生态学报》2015年第10期3139-3147,共9页Acta Ecologica Sinica

基　　金：江苏高校优秀学科建设工程资助项目(164320H106)

摘　　要：一氧化氮(NO)作为一种重要的信号分子,在调节植物重金属胁迫抗性方面上起着非常重要的作用。综述了NO在植物体内的产生途径,重金属胁迫下植物体内内源NO含量的变化以及外源NO与内源NO对植物重金属胁迫抗性的影响。大量研究表明外源NO能够增强植物对重金属胁迫的抗性,一方面是通过增强植物细胞的抗氧化系统或直接清除活性氧,另一方面是通过影响植物对重金属的吸收以及重金属在植物细胞内的分布。然而内源NO在调节植物重金属胁迫抗性上的功能角色仍存在争议。有些研究表明内源NO是有益的,能够缓解重金属胁迫诱导的毒性;但是也有证据表明内源NO是有害的,能够通过促进植物对重金属的吸收以及对植物螯合素进行S-亚硝基化弱化其解毒功能,从而参与重金属诱导的毒害反应和细胞凋亡过程。Heavy metal pollution has become an increasingly serious environmental problem because heavy metal can be easily taken up by plants, leading to inhibition of plant growth and development. Hence, it is necessary to investigate resistances of plants to heavy metal stress. As an important signaling molecule, nitric oxide （NO） is involved in the regulation of multiple plant responses to a variety of abiotic and biotic stresses. Recently, an increasing number of articles have reported the effects of NO on resistances of plants to heavy metal stress. However, studies which systematically summarize the molecular mechanisms of NO on resistances of plants to heavy metal stress are quite limited. This research mainly reviews the pathways of NO production, changes of endogenous NO contents under heavy metal stress and influences of exogenous and endogenous NO on resistances to heavy metal stress. The sources of NO production in plants involve not only enzymatic reaction pathways which include nitric oxide synthase （NOS）, nitrate reductase （NR）, nitrite reductase （Ni-NOR） pathways and etc. but also non-enzymatic reaction pathways. Many authors have noted discrepant reports on the effects of heavy metal stress on endogenous NO content in plants and the observed differences in endogenous NO accumulation are frequently ascribed to the use of different duration of treatment, heavy metal concentrations, species and genotypes of plants and varieties of plant tissues. Interestingly, all plant cell suspensions show a visible increase in endogenous NO accumulation under heavy metal stress, which is attributed to the fact that they are lacking of network regulation between cells and cells. Meanwhile, it has been demonstrated that exogenous NO could enhance antioxidant defence system of plant cells, act as an antioxidant promoting direct scavenging of reactive oxygen species, induce metallothioneins （MTs） gene expression by displacing heavy metal bound to MTs, and affect the uptake of heavy metal into plants and the

关 键 词：外源NO 内源NO 重金属胁迫 抗性 

分 类 号：Q945.78[生物学—植物学]