Nitrogen, phosphorous and potassium are essential nutrients for plant growth and development. However, their contents in soils are limited so that crop production needs to invest a lot for fertilizer supply. To explor...Nitrogen, phosphorous and potassium are essential nutrients for plant growth and development. However, their contents in soils are limited so that crop production needs to invest a lot for fertilizer supply. To explore the genetic potentialities of crops （or plants） for their nutrient utilization efficiency has been an important research task for many years, in fact, a number of evidences have revealed that plants, during their evolution, have developed many morphological, physiological, biochemical and molecular adaptation mechanisms for acquiring nitrate, phosphate and potassium under stress conditions. Recent discoveries of many transporters and channels for nitrate, phosphate and potassium uptake have opened up opportunities to study the molecular regulatory mechanisms for acquisition of these nutrients. This review aims to briefly discuss the genes and gene families for these transporters and channels, in addition, the functions and regulation of some important transporters and channels are particularly emphasized.展开更多
Rice （Oryza sativa） grown in paddy fields is an ammonium （NH4^＋）-preferring crop; however, its AMT-type NH4^＋ transporters that mediate root N acquisition have not been well characterized yet. In this study, we ...Rice （Oryza sativa） grown in paddy fields is an ammonium （NH4^＋）-preferring crop; however, its AMT-type NH4^＋ transporters that mediate root N acquisition have not been well characterized yet. In this study, we analyzed the expression pattern and physiological function of the OsAMT1.1 gene of the AMT1 subfamily in rice. OsAMT1.1 is located in the plasma membrane and is mainly expressed in the root epidermis, stele and mesophyll cells. Disruption of the OsAMTI.1 gene decreased the uptake of NH4^＋, and the growth of roots and shoots under both low NH4^＋ and high NH4^＋ conditions. OsAMT1.1 contributed to the short-term （5 min） ^15NH4^＋ influx rate by approximately one-quarter, irrespective of the NH4^＋ concentration. Knockout of OsAMTI.I significantly decreased the total N transport from roots to shoots under low NH4^＋ conditions. Moreover, compared with the wild type, the osamt1.1 mutant showed an increase in the potassium （K） absorption rate under high NH4^＋ conditions and a decrease under low NH4^＋ conditions. The mutants contained a significantly high concentration of K in both the roots and shoots at a limited K （0.1 mmol/L） supply when NH4^＋ was replete. Taken together, the results indicated that OsAMT1.1 significantly contributes to the NH4^＋ uptake under both low and high NH4^＋ conditions and plays an important role in N-K homeostasis in rice.展开更多
As one of the most important mineral nutrient elements, potassium(K^+) plays an important role in many plant physiological processes and determines both the yield and quality of crops. There are two typical gene famil...As one of the most important mineral nutrient elements, potassium(K^+) plays an important role in many plant physiological processes and determines both the yield and quality of crops. There are two typical gene families that regulate K^+transport in higher plants, including K^+channels and K^+transporters. However, little is known about how these channels and transporters divide their work in response to drought stress. In this study, the hydroponic experiment was conducted on Malus hupehensis. The K^+content was found to decrease in response to drought stress in M. hupehensis, the aboveground decreased by 34.15% and the underground decreased by 3.97%. Meanwhile, the root morphology change was detected by scanning the root system. Under conditions of drought, the genes encoding K^+transporters were upregulated including MdCHX1.3, MdCHX4.11, MdCHX4.8, MdCHX4.9, Md HKT1, and MdHAK3.2. The net influx of K^+was inhibited by 19.47% with the action of K^+channel inhibitors(CsCl), however a significant decrease(80.99%; P < 0.05) was found in roots exposed to a PM H+-ATPase(orthovanadate) inhibitor by utilizing a non-invasive micro-test technique. The trend of H+efflux was similar to that of K^+. The data suggested that the positive influx of K^+through the transporter accounted for the main K^+uptake under drought stress. These results suggest that we can improve the uptake of K^+by purposely up-regulating specific K^+transporters under drought stress. This process may improve growth, yield, quality, and stress tolerance in apple trees.展开更多
Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene ...Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.展开更多
Potassium(K) is an essential macronutrient for plant growth and development and influences yield and quality of agricultural crops.Maize(Zea mays) is one of the most widely distributed crops worldwide.In China,althoug...Potassium(K) is an essential macronutrient for plant growth and development and influences yield and quality of agricultural crops.Maize(Zea mays) is one of the most widely distributed crops worldwide.In China,although maize consumes a large amount of K fertilizer,the K uptake/utilization efficiency(KUE)of maize cultivars is relatively low.Elucidation of KUE mechanisms and development of maize cultivars with higher KUE are needed.Maize KUE is determined by K+uptake,transport,and remobilization,which depend on a variety of K+channels and transporters.We review basic information about K+channels and transporters in maize,their functions and regulation,and the roles of K+in nitrogen transport,sugar transport,and salt tolerance.We discuss challenges and prospects for maize KUE improvement.展开更多
Adventitious root formation is a bottleneck during vegetative proliferation.Potassium(K^(+))is an essential macronutrient for plants.K^(+)accumulation from the soil and its distribution to the different plant organs i...Adventitious root formation is a bottleneck during vegetative proliferation.Potassium(K^(+))is an essential macronutrient for plants.K^(+)accumulation from the soil and its distribution to the different plant organs is mediated by K^(+)transporters named K^(+)transporter(KT),K^(+)uptake(KUP),or high-affinity K^(+)(HAK).This study aimed to identify members of the HAK gene family in apples and to characterize the effects of K^(+)supply on adventitious root formation and on the expression of HAK genes and the genes that putatively control auxin transport,signaling,and cell fate during adventitious root formation.In this study,34 HAK genes(MdHAKs)were identified in the apple(Malus×domestica‘Golden Delicious’)genome.A phylogenetic analysis divided MdHAKs into four clusters(Ⅰ,Ⅱ,Ⅲ,andⅣ),comprising 16,1,4,and 13 genes,respectively.The syntenic relationships revealed that 62.5%of the total MdHAK genes arise from genomic duplication events.Chromosome location,domain structure,motif analysis,and physico-chemical characteristics were subsequently investigated.Furthermore,the application of K^(+)indicated the emergence of adventitious roots at 8 d and produced more adventitious roots at 16 d than the K^(+)-free control(CK)treatment.In addition,various MdHAKs showed root-specific expression in B9 apple rootstock stem cuttings and enhanced expression during the initiation and emergence stages of adventitious root formation in response to K^(+)treatment.Additionally,K^(+)treatment enhanced the expression levels of MdPIN1,MdPIN2,and MdAUX1.Further data indicated that a higher expression of MdWOX11,MdLBD16,and MdLBD29 and of cell cycle-related genes contributed to the auxin-stimulated adventitious root formation in response to K^(+).展开更多
Potassium is an essential nutrient for plant growth and productivity of crops. K+transporters are important for K+uptake and transport in plants. However,information on the function of K+transporters and K+channels in...Potassium is an essential nutrient for plant growth and productivity of crops. K+transporters are important for K+uptake and transport in plants. However,information on the function of K+transporters and K+channels in cotton is limited. The KT/KUP/HAK protein family is essential for a variety of physiological processes in plants, including nutrient acquisition and regulation of development. This study, identified a K+transporter gene,Gh KT2, expressed in the roots of cotton(Gossypium hirsutum) cv. Liaomian17. The deduced transcript of Gh KT2 is highly homologous to Cluster II of KUP/HAK/KT K+transporters and is predicted to contain 11 transmembrane domains. Gh KT2 has been localized to the plasma membrane, and its transcripts were detected in roots, stems, leaves and shoot apices of cotton seedlings.Consistently, b-glucuronidase(GUS) expression driven by the Gh KT2 promoter could be detected in roots, mesophyll cells, and leaf veins in transgenic Arabidopsis. In addition,the expression of Gh KT2 was induced by low K+stress in cotton roots and p Gh KT2::GUS-transgenic Arabidopsis seedlings. The Gh KT2-overexpression Arabidopsis lines plants were larger and showed greater K+accumulation than the wild type(WT) regardless of K+concentration supplied. The net K+influx rate, measured by the noninvasive micro-test technique, in root meristem zone of Gh KT2-transgenic Arabidopsis lines was significantly greater than that of WT. Taken together, this evidence indicates that Gh KT2 may participate in K+acquisition from low or high external K+, as well as K+transport and distribution in plants.展开更多
文摘Nitrogen, phosphorous and potassium are essential nutrients for plant growth and development. However, their contents in soils are limited so that crop production needs to invest a lot for fertilizer supply. To explore the genetic potentialities of crops （or plants） for their nutrient utilization efficiency has been an important research task for many years, in fact, a number of evidences have revealed that plants, during their evolution, have developed many morphological, physiological, biochemical and molecular adaptation mechanisms for acquiring nitrate, phosphate and potassium under stress conditions. Recent discoveries of many transporters and channels for nitrate, phosphate and potassium uptake have opened up opportunities to study the molecular regulatory mechanisms for acquisition of these nutrients. This review aims to briefly discuss the genes and gene families for these transporters and channels, in addition, the functions and regulation of some important transporters and channels are particularly emphasized.
基金supported by the grants of the National Key Research and Development Program of China(No.2016yfd0100700)the 111 Project(No.12009)+1 种基金the Innovative Research Team Development Plan of the Ministry of Education of Chinathe PAPD of Jiangsu Higher Education Institutions Project
文摘Rice （Oryza sativa） grown in paddy fields is an ammonium （NH4^＋）-preferring crop; however, its AMT-type NH4^＋ transporters that mediate root N acquisition have not been well characterized yet. In this study, we analyzed the expression pattern and physiological function of the OsAMT1.1 gene of the AMT1 subfamily in rice. OsAMT1.1 is located in the plasma membrane and is mainly expressed in the root epidermis, stele and mesophyll cells. Disruption of the OsAMTI.1 gene decreased the uptake of NH4^＋, and the growth of roots and shoots under both low NH4^＋ and high NH4^＋ conditions. OsAMT1.1 contributed to the short-term （5 min） ^15NH4^＋ influx rate by approximately one-quarter, irrespective of the NH4^＋ concentration. Knockout of OsAMTI.I significantly decreased the total N transport from roots to shoots under low NH4^＋ conditions. Moreover, compared with the wild type, the osamt1.1 mutant showed an increase in the potassium （K） absorption rate under high NH4^＋ conditions and a decrease under low NH4^＋ conditions. The mutants contained a significantly high concentration of K in both the roots and shoots at a limited K （0.1 mmol/L） supply when NH4^＋ was replete. Taken together, the results indicated that OsAMT1.1 significantly contributes to the NH4^＋ uptake under both low and high NH4^＋ conditions and plays an important role in N-K homeostasis in rice.
基金supported by the National Key Research and Development Program of China(2016YFD0201102)the earmarked fund for the China Agriculture Research System(CARS-28)+1 种基金Agricultural Science and Technology Innovation and Tackling Project of Shaanxi(2016NY-070)the fund for the China Apple Technology System(CARS-27)
文摘As one of the most important mineral nutrient elements, potassium(K^+) plays an important role in many plant physiological processes and determines both the yield and quality of crops. There are two typical gene families that regulate K^+transport in higher plants, including K^+channels and K^+transporters. However, little is known about how these channels and transporters divide their work in response to drought stress. In this study, the hydroponic experiment was conducted on Malus hupehensis. The K^+content was found to decrease in response to drought stress in M. hupehensis, the aboveground decreased by 34.15% and the underground decreased by 3.97%. Meanwhile, the root morphology change was detected by scanning the root system. Under conditions of drought, the genes encoding K^+transporters were upregulated including MdCHX1.3, MdCHX4.11, MdCHX4.8, MdCHX4.9, Md HKT1, and MdHAK3.2. The net influx of K^+was inhibited by 19.47% with the action of K^+channel inhibitors(CsCl), however a significant decrease(80.99%; P < 0.05) was found in roots exposed to a PM H+-ATPase(orthovanadate) inhibitor by utilizing a non-invasive micro-test technique. The trend of H+efflux was similar to that of K^+. The data suggested that the positive influx of K^+through the transporter accounted for the main K^+uptake under drought stress. These results suggest that we can improve the uptake of K^+by purposely up-regulating specific K^+transporters under drought stress. This process may improve growth, yield, quality, and stress tolerance in apple trees.
基金supported by the National Natural Science Foundation of China(Grant Nos.32272169,32000377,32172037,and 31601387)the Natural Science Foundation of Guangdong Province(Grant No.2022A1515110449)the Hainan Yazhou Bay Seed Laboratory(project of B21HJ1002)。
文摘Soil salinity has a major impact on rice seed germination,severely limiting rice production.Herein,a rice germination defective mutant under salt stress(gdss)was identified by using chemical mutagenesis.The GDSS gene was detected via MutMap and shown to encode potassium transporter OsHAK9.Phenotypic analysis of complementation and mutant lines demonstrated that OsHAK9 was an essential regulator responsible for seed germination under salt stress.OsHAK9 is highly expressed in germinating seed embryos.Ion contents and non-invasive micro-test technology results showed that OsHAK9 restricted K^(+)efflux in salt-exposed germinating seeds for the balance of K^(+)/Na^(+).Disruption of OsHAK9 significantly reduced gibberellin 4(GA4)levels,and the germination defective phenotype of oshak9a was partly rescued by exogenous GA_(3)treatment under salt stress.RNA sequencing(RNA-seq)and real-time quantitative polymerase chain reaction analysis demonstrated that the disruption of OsHAK9 improved the GA-deactivated gene OsGA2ox7 expression in germinating seeds under salt stress,and the expression of OsGA2ox7 was significantly inhibited by salt stress.Null mutants of OsGA2ox7 created using clustered,regularly interspaced,short palindromic repeat(CRISPR)/CRISPR-associated nuclease 9 approach displayed a dramatically increased seed germination ability under salt stress.Overall,our results highlight that OsHAK9 regulates seed germination performance under salt stress involving preventing GA degradation by mediating OsGA2ox7,which provides a novel clue about the relationship between GA and OsHAKs in rice.
基金supported by the National Key Research and Development Program of China (2021YFF1000500)National Natural Science Foundation of China (32025004, 32161133014, and31921001)Beijing Outstanding University Discipline Program。
文摘Potassium(K) is an essential macronutrient for plant growth and development and influences yield and quality of agricultural crops.Maize(Zea mays) is one of the most widely distributed crops worldwide.In China,although maize consumes a large amount of K fertilizer,the K uptake/utilization efficiency(KUE)of maize cultivars is relatively low.Elucidation of KUE mechanisms and development of maize cultivars with higher KUE are needed.Maize KUE is determined by K+uptake,transport,and remobilization,which depend on a variety of K+channels and transporters.We review basic information about K+channels and transporters in maize,their functions and regulation,and the roles of K+in nitrogen transport,sugar transport,and salt tolerance.We discuss challenges and prospects for maize KUE improvement.
基金financially supported by the National Key Research and Development Program of China(Grant No.2018YFD1000101,2019YFD1000803)Shaanxi Apple Industry Science and Technology Project(Grant No.2020zdzx03-01-04)+1 种基金Tang Scholar by Cyrus Tang Foundation(Grant No.C200022002)The China Apple Research System(Grant No.CARS-27).
文摘Adventitious root formation is a bottleneck during vegetative proliferation.Potassium(K^(+))is an essential macronutrient for plants.K^(+)accumulation from the soil and its distribution to the different plant organs is mediated by K^(+)transporters named K^(+)transporter(KT),K^(+)uptake(KUP),or high-affinity K^(+)(HAK).This study aimed to identify members of the HAK gene family in apples and to characterize the effects of K^(+)supply on adventitious root formation and on the expression of HAK genes and the genes that putatively control auxin transport,signaling,and cell fate during adventitious root formation.In this study,34 HAK genes(MdHAKs)were identified in the apple(Malus×domestica‘Golden Delicious’)genome.A phylogenetic analysis divided MdHAKs into four clusters(Ⅰ,Ⅱ,Ⅲ,andⅣ),comprising 16,1,4,and 13 genes,respectively.The syntenic relationships revealed that 62.5%of the total MdHAK genes arise from genomic duplication events.Chromosome location,domain structure,motif analysis,and physico-chemical characteristics were subsequently investigated.Furthermore,the application of K^(+)indicated the emergence of adventitious roots at 8 d and produced more adventitious roots at 16 d than the K^(+)-free control(CK)treatment.In addition,various MdHAKs showed root-specific expression in B9 apple rootstock stem cuttings and enhanced expression during the initiation and emergence stages of adventitious root formation in response to K^(+)treatment.Additionally,K^(+)treatment enhanced the expression levels of MdPIN1,MdPIN2,and MdAUX1.Further data indicated that a higher expression of MdWOX11,MdLBD16,and MdLBD29 and of cell cycle-related genes contributed to the auxin-stimulated adventitious root formation in response to K^(+).
基金supported by the Genetically Modified Organisms Breeding Major Projects of China Grant (2014ZX08005-004)
文摘Potassium is an essential nutrient for plant growth and productivity of crops. K+transporters are important for K+uptake and transport in plants. However,information on the function of K+transporters and K+channels in cotton is limited. The KT/KUP/HAK protein family is essential for a variety of physiological processes in plants, including nutrient acquisition and regulation of development. This study, identified a K+transporter gene,Gh KT2, expressed in the roots of cotton(Gossypium hirsutum) cv. Liaomian17. The deduced transcript of Gh KT2 is highly homologous to Cluster II of KUP/HAK/KT K+transporters and is predicted to contain 11 transmembrane domains. Gh KT2 has been localized to the plasma membrane, and its transcripts were detected in roots, stems, leaves and shoot apices of cotton seedlings.Consistently, b-glucuronidase(GUS) expression driven by the Gh KT2 promoter could be detected in roots, mesophyll cells, and leaf veins in transgenic Arabidopsis. In addition,the expression of Gh KT2 was induced by low K+stress in cotton roots and p Gh KT2::GUS-transgenic Arabidopsis seedlings. The Gh KT2-overexpression Arabidopsis lines plants were larger and showed greater K+accumulation than the wild type(WT) regardless of K+concentration supplied. The net K+influx rate, measured by the noninvasive micro-test technique, in root meristem zone of Gh KT2-transgenic Arabidopsis lines was significantly greater than that of WT. Taken together, this evidence indicates that Gh KT2 may participate in K+acquisition from low or high external K+, as well as K+transport and distribution in plants.
