An Arabidopsis mutant of inositol pentakisphosphate 2-kinase AtIPK1 displays reduced arsenate tolerance
An Arabidopsis mutant of inositol pentakisphosphate 2-kinase AtIPK1 displays reduced arsenate tolerance
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拟南芥肌醇五磷酸 2-激酶 AtIPK1 突变体表现出砷酸盐耐受性降低
DOI：
10.1111/pce.12623
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发表时间：
2016
影响因子：
7.3
通讯作者：
Ma Mi
中科院分区：
文献类型：
--
作者：
Sun Yang-Yang;Xu Wen-Zhong;Wu Li;Wang Ruo-Zhong;He Zhen-Yan;Ma Mi
砷酸盐[As（V）]的毒性被认为是由于As（V）和磷酸盐（Pi）的化学性质相似。与野生型（WT）相比，五磷酸肌醇2-激酶（AtIPK 1）的拟南芥突变体atipk 1 - 1先前表现出较低的植酸水平和较高的Pi水平。在此，与WT相比，atipk 1 - 1显示出对As（V）应激的超敏反应和较少的As（V）摄取。由CaMV 35 S启动子控制的AtIPK 1的过表达部分挽救了Fatipk 1 - 1的As（V）敏感表型。与对照组相比，添加Pi增强了WT和atipk 1 - 1植株对As（V）的耐受性，而后者基因型中砷浓度降低较少。尽管与WT植株相比，atipk 1 - 1中的Pi水平更高，但在Pi限制胁迫下，突变体遭受更严重的Pi饥饿，表明突变体中的Pi稳态被改变。WT和atipk 1 - 1植物的基因表达分析表明，As（V）胁迫对Pi饥饿依赖的Pi响应基因的调节具有不同的影响。本研究表明，在atipk 1 - 1突变体中存在一种特殊的As（V）毒害机制，这可能为植物体内磷稳态与As（V）解毒之间的相互作用提供新的认识。
Arsenate [As(V)] toxicity is considered to be derived from similarities in the chemical properties of As(V) and phosphate (Pi). AnArabidopsis thalianamutant of inositol pentakisphosphate 2‐kinase (AtIPK1),atipk1‐1, has previously exhibited lower level of phytate and higher level of Pi, relative to wild‐type (WT). Here,atipk1‐1displayed hypersensitivity to As(V) stress and less As(V) uptake when compared to WT. Overexpression ofAtIPK1controlled by the CaMV 35S promoter partially rescued the As(V)‐sensitive phenotype ofatipk1‐1. When compared to control Pi status, addition of Pi enhanced As(V) tolerance of both WT andatipk1‐1plants, while the arsenic concentration was less reduced in the latter genotype. Despite the higher Pi level inatipk1‐1than did WT plants, the mutant suffered more severe Pi starvation under Pi limitation stress, indicating that Pi homeostasis was altered in the mutant. Gene expression analysis of WT andatipk1‐1plants showed the diverse effect of As(V) stress on Pi starvation‐dependent regulation of Pi‐responsive genes. Our study suggested that a particular mechanism of As(V) toxicity existed inatipk1‐1mutant, and may offer new insights into the interactions between Pi homeostasis and As(V) detoxification in plants.