In China,19%of agricultural soils contain harmful heavy metal pollutants at levels exceeding environmentally recommended standards,whilst around 3 million hectares of arable land are too polluted to grow crops on(Zhao...In China,19%of agricultural soils contain harmful heavy metal pollutants at levels exceeding environmentally recommended standards,whilst around 3 million hectares of arable land are too polluted to grow crops on(Zhao et al.,2015;Hu et al.,2016).Among the deleterious heavy metals,cadmium(Cd)is the most bioavailable toxic metallic pollutant and is rapidly transferable through the food chain(Wang et al.,2019).Concerning the current dilemma of the enhanced food demands of a rising population and decreasing availability of arable land,it is promising to cultivate field crops that produce enough safe foods for human consumption and simultaneously remove the pollutants from contaminated arable lands.展开更多
Nitrogen is an essential nutrient for plant growth and development,and plays vital roles in crop yield.Assimilation of nitrogen is thus fine-tuned in response to heterogeneous environments.However,the regulatory mecha...Nitrogen is an essential nutrient for plant growth and development,and plays vital roles in crop yield.Assimilation of nitrogen is thus fine-tuned in response to heterogeneous environments.However,the regulatory mechanism underlying this essential process remains largely unknown.Here,we report that a zinc-finger transcription factor,drought and salt tolerance(DST),controls nitrate assimilation in rice by regulating the expression of OsNR1.2.We found that loss of function of DSTresults in a significant decrease of nitrogen use efficiency(NUE)in the presence of nitrate.Furtherstudy revealed that DST is required for full nitrate reductase activity in rice and directly regulates the expression of OsNR1.2,a gene showing sequence similarity to nitrate reductase.Reverse genetics and biochemistry studies revealed that OsNR1.2 encodes an NADH-dependent nitrate reductase that is required for high NUE of rice.Interestingly,the DST-OsNR1.2 regulatory module is involved in the suppression of nitrate assimilation under drought stress,which contributes to drought tolerance.Considering the negative role of DST in stomata closure,as revealed previously,the positive role of DST in nitrogen assimilation suggests a mechanism couplingni-trogen metabolism and stomata movement.The discovery of this coupling mechanism will aid the engi-neering of drought-tolerant crops with high NUE in the future.展开更多
基金supported by National Key Research and Development Program of China(2020YFE0202300)the National Natural Science Foundation of China(31961133002)+1 种基金Chinese Academy of Sciences(XDB27010000)Sichuan Science and Technology Program(2018HH0160).
文摘In China,19%of agricultural soils contain harmful heavy metal pollutants at levels exceeding environmentally recommended standards,whilst around 3 million hectares of arable land are too polluted to grow crops on(Zhao et al.,2015;Hu et al.,2016).Among the deleterious heavy metals,cadmium(Cd)is the most bioavailable toxic metallic pollutant and is rapidly transferable through the food chain(Wang et al.,2019).Concerning the current dilemma of the enhanced food demands of a rising population and decreasing availability of arable land,it is promising to cultivate field crops that produce enough safe foods for human consumption and simultaneously remove the pollutants from contaminated arable lands.
基金This study was funded by the Ministry of Science and Technology Key R&D program(2016YFD0100700 to D.Y.C.)Chinese Academy of Sciences(XDB27010103 to D.Y.C)National Natural Science Foundation of China(31801922 to M.L.H).
文摘Nitrogen is an essential nutrient for plant growth and development,and plays vital roles in crop yield.Assimilation of nitrogen is thus fine-tuned in response to heterogeneous environments.However,the regulatory mechanism underlying this essential process remains largely unknown.Here,we report that a zinc-finger transcription factor,drought and salt tolerance(DST),controls nitrate assimilation in rice by regulating the expression of OsNR1.2.We found that loss of function of DSTresults in a significant decrease of nitrogen use efficiency(NUE)in the presence of nitrate.Furtherstudy revealed that DST is required for full nitrate reductase activity in rice and directly regulates the expression of OsNR1.2,a gene showing sequence similarity to nitrate reductase.Reverse genetics and biochemistry studies revealed that OsNR1.2 encodes an NADH-dependent nitrate reductase that is required for high NUE of rice.Interestingly,the DST-OsNR1.2 regulatory module is involved in the suppression of nitrate assimilation under drought stress,which contributes to drought tolerance.Considering the negative role of DST in stomata closure,as revealed previously,the positive role of DST in nitrogen assimilation suggests a mechanism couplingni-trogen metabolism and stomata movement.The discovery of this coupling mechanism will aid the engi-neering of drought-tolerant crops with high NUE in the future.
