质膜H^(+)-ATPase基因对铝胁迫下水稻硝态氮吸收的 调控作用

Regulation of Plasma Membrane H^(+)-ATPase Genes on Nitrate Nitrogen Uptake in Rice under Aluminum Stress

为探讨细胞质膜ATP酶(PM H^(+)-ATPase)基因对铝胁迫下水稻(Oryza sativa L.)吸收硝态氮(NO_(3)^(-)-N)的调控,本试验以2个水稻品种峰1A和峰1A优5为研究对象,以无铝处理幼苗为对照,分析铝胁迫下水稻根尖PM H^(+)-ATPase活性、H^(+)-泵活性、H^(+)通量、PM H^(+)-ATPase基因家族(OsA1~OsA10)表达水平、PM H^(+)-ATPase和14-3-3蛋白的互作水平以及NO_(3)^(-)-N吸收量。结果表明,与对照相比,铝胁迫下2个水稻品种根尖PM H^(+)-ATPase活性、H^(+)-泵活性和根尖H^(+)通量下降,PM H^(+)-ATPase和14-3-3蛋白的互作水平下降。铝胁迫抑制了OsA1、OsA5、OsA7和OsA8基因的表达,其中OsA7的表达水平显著下调,铝胁迫下峰1A和峰1A优5的OsA7表达量仅为对照组的21%和39%。NO_(3)^(-)-N吸收量较对照下降,分别为对照的81%和85%。综上,PM H^(+)-ATPase基因的表达水平影响水稻对NO_(3)^(-)-N的吸收能力,OsA1、OsA5、OsA7和OsA8在铝胁迫下水稻吸收NO_(3)^(-)-N过程中起关键的调控作用。本研究结果可为增强酸铝条件下水稻吸收NO_(3)^(-)-N的能力,促进水稻生长及增产提供理论依据。

To explore the regulation of nitrate nitrogen absorption(NO_(3)^(-)-N)by the cell plasma membrane ATP enzyme(PM H^(+)-ATPase)gene in rice under aluminum(Al)stress,two rice varieties,Feng 1A and Feng 1A super 5,were studied and seedlings without Al treatment were used as control.The activities of PM H^(+)-ATPase hydrolysis and H^(+)-pump,H^(+)efflux,the expression levels of PM H^(+)-ATPase gene(OsA1-OsA10),the level of interaction of PM H^(+)-ATPase and 14-3-3 protein were analysed.The results showed that,the activities of PM H^(+)-ATPase hydrolysis and H^(+)-pump,H^(+)efflux,the level of interaction of PM H^(+)-ATPase and 14-3-3 protein showed a decrease compared with the control.The expression of gene OsA1,OsA5,OsA7 and OsA8 were suppressed.The expression level of OsA7 in Feng 1A and Feng 1A super 5 under Al stress were only 21%and 39%of the control,respectively,and the difference is significant.The uptake of NO_(3)^(-)-N of two rice varieties are 81%and 85%of the control,respectively.In conclusion,the expression level of PM H^(+)-ATPase gene affected the absorption capacity of NO_(3)^(-)-N in rice,OsA1,OsA5,OsA7 and OsA8 could play a key regulatory role in the process of NO_(3)^(-)-N absorption under Al stress.This study provides a theoretical basis for enhancing the ability of rice to absorb NO_(3)^(-)-N under acidic Al conditions,thereby promoting their growth and yield.