氮(N)是植物生长发育需要量最大的矿质营养元素,也是作物产量的限制因子。硝态氮(NO_(3)^(-)-N)是植物吸收利用氮素的主要形态之一。目前,植物中已报道4个基因家族(NPF、NRT2、CLC和SLAC1/SLAH)参与硝态氮的吸收和利用,其中NPF基因家族...氮(N)是植物生长发育需要量最大的矿质营养元素,也是作物产量的限制因子。硝态氮(NO_(3)^(-)-N)是植物吸收利用氮素的主要形态之一。目前,植物中已报道4个基因家族(NPF、NRT2、CLC和SLAC1/SLAH)参与硝态氮的吸收和利用,其中NPF基因家族成员数量众多且功能多样化,近年来获得较多关注和深入研究。模式植物拟南芥和主要粮食作物水稻、玉米和小麦中,分别含有53、93、79和331个NPF基因。拟南芥NPF家族中已有超过一半成员(31/53)的生物学功能被解析,粮食作物水稻中NPF基因功能亦有较多报道。研究表明,NPF基因广泛参与了植物对氮素的吸收及其调控、转运、分配/再分配等过程,一些成员对于改良和提高作物氮素利用率(nitrogen use efficiency,NUE)具有重要作用。因此,从氮素进入植物体及其在植物体内流动的层面出发,发掘具有重要功能的候选NPF基因,对于解析植物利用氮素的分子机制及其遗传改良具有重要意义。本文综述了模式植物拟南芥以及粮食作物中已报道的NPF基因在氮素吸收和利用中的生物学功能。目前粮食作物玉米中仅有4个NPF基因的生物学功能被报道,小麦中尚未有相关报道,未来对玉米和小麦中NPF基因的发掘与功能研究将为改良作物氮素利用效率提供新的基因资源。展开更多
The com borer is a world-wide agricultural pest.In this study,a high-efficiency RNAi method was explored to knock down the neuropeptide F(NPF)to determine if NPF regulates larval feeding in the Asian corn borer,Ostrin...The com borer is a world-wide agricultural pest.In this study,a high-efficiency RNAi method was explored to knock down the neuropeptide F(NPF)to determine if NPF regulates larval feeding in the Asian corn borer,Ostrinia furnacalis.Results showed that the expression peaks of npfmRNA in both midgut and fat body are at 28 h of early 5th instar larvae.When NPF was kno eked dow n either by feedi ng dsNPF-c ontaining artificial diet or direct dsNPF in jection into the 5th in star larvae,npf expression was effectively inhibited in the midgut.Larval feeding,body weight and development time were significantly impacted.In con trast,the expressi on of the npf receptors npfrl and npfr2 in fat body of 5th in star larvae was sign ifica ntly increased by dsNPF injection.These results indicate that NPF can be effectively knoeked down in 0.furnacalis,and dsNPF by injection is an effective and fast way to silence npf expression.This study provides a critical basis for further exploration in mechanism of feeding regulation in 0.furnacalis.展开更多
Particle number size distribution from 10 to 10,000 nm was measured by a wide-range particle spectrometer (WPS-1000XP) at a downwind site north of downtown Lanzhou, western China, from 25 june to 19 July 2006. We fi...Particle number size distribution from 10 to 10,000 nm was measured by a wide-range particle spectrometer (WPS-1000XP) at a downwind site north of downtown Lanzhou, western China, from 25 june to 19 July 2006. We first report the pollution level, diurnal variation of particle concentration in different size ranges and then introduce the characteristics of the particle formation processes, to show that the number concentration of ultrafine particles was lower than the values measured in other urban or suburban areas in previous studies, However, the fraction of ultrafine particles in total aerosol number concentration was found to be much higher. Furthermore, sharp increase of ultrafine particle concentration was frequently observed at noon. An examination of the diurnal pattern suggests that the burst of the ultrafine particles was mainly due to nucleation process. During the 25-day observation, new particle formation (NPF) from homogeneous nucleation was observed during 33% of the study period. The average growth rate of the newly formed particles was 4.4 nm/h, varying from 1.3 to 16,9 nm/h. The needed concentration of condensable vapor was 6.1 × 10^7 cm-3, and its source rate was 1.1× 10^6 cm-3 s 1. Further calculation on the source rate of sulphuric acid vapor indicated that the average participation of sulphuric acid to particle growth rate was 68.3%.展开更多
Abscisic acid(ABA)transport plays an important role in systemic plant responses to environmental factors.However,it remains largely unclear about the precise regulation of ABA transporters in plants.In this study,we s...Abscisic acid(ABA)transport plays an important role in systemic plant responses to environmental factors.However,it remains largely unclear about the precise regulation of ABA transporters in plants.In this study,we show that the C-terminally encoded peptide receptor 2(CEPR2)directly interacts with the ABA transporter NRT1.2/NPF4.6.Genetic and phenotypic analyses revealed that NRT1.2/NPF4.6 positively regulates ABA response and that NRT1.2/NPF4.6 is epistatically and negatively regulated by CEPR2.Further biochemical assays demonstrated that CEPR2 phosphorylates NRT1.2/NPF4.6 at serine 292 to promote its degradation under normal conditions.However,ABA treatment and non-phosphorylation at serine 292 prevented the degradation of NRT1.2/NPF4.6,indicating that ABA inhibits the phosphorylation of this residue.Transport assays in yeast and Xenopus oocytes revealed that non-phosphorylated NRT1.2/NPF4.6 had high levels of ABA import activity,whereas phosphorylated NRT1.2/NPF4.6 did not import ABA.Analyses of complemented nrt1.2 mutants that mimicked non-phosphorylated and phosphorylated NRT1.2/NPF4.6 confirmed that non-phosphorylated NRT1.2S292A had high stability and ABA import activity in planta.Additional experiments showed that NRT1.2/NPF4.6 was degraded via the 26S proteasome and vacuolar degradation pathways.Furthermore,we found that three E2 ubiquitin-conjugating enzymes,UBC32,UBC33,and UBC34,interact with NRT1.2/NPF4.6 in the endoplasmic reticulum and mediate its ubiquitination.NRT1.2/NPF4.6 is epistatically and negatively regulated by UBC32,UBC33,and UBC34 inplanta.Taken together,these results suggest that the stability and ABA import activity of NRT1.2/NPF4.6 are precisely regulated by its phosphorylation and degradation in response to environmental stress.展开更多
Iron(Fe)transport and reallocation are essential to Fe homeostasis in plants,but it is unclear how Fe homeostasis is regulated,especially under stress.Here we report that NPF5.9 and its close homolog NPF5.8 redundantl...Iron(Fe)transport and reallocation are essential to Fe homeostasis in plants,but it is unclear how Fe homeostasis is regulated,especially under stress.Here we report that NPF5.9 and its close homolog NPF5.8 redundantly regulate Fe transport and reallocation in Arabidopsis.NPF5.9 is highly upregulated in response to Fe deficiency.NPF5.9 expresses preferentially in vasculature tissues and localizes to the trans-Golgi network,and NPF5.8 showed a similar expression pattern.Long-distance Fe transport and allocation into aerial parts was significantly increased in NPF5.9-overexpressing lines.In the double mutant npf5.8 npf5.9,Fe loading in aerial parts and plant growth were decreased,which were partially rescued by Fe supplementation.Further analysis showed that expression of PYE,the negative regulator for Fe homeostasis,and its downstream target NAS4 were significantly altered in the double mutant.NPF5.9 and NPF5.8 were shown to also mediate nitrate uptake and transport,although nitrate and Fe application did not reciprocally affect each other.Our findings uncovered the novel function of NPF5.9 and NPF5.8 in long-distance Fe transport and homeostasis,and further indicated that they possibly mediate nitrate transport and Fe homeostasis independently in Arabidopsis.展开更多
文摘氮(N)是植物生长发育需要量最大的矿质营养元素,也是作物产量的限制因子。硝态氮(NO_(3)^(-)-N)是植物吸收利用氮素的主要形态之一。目前,植物中已报道4个基因家族(NPF、NRT2、CLC和SLAC1/SLAH)参与硝态氮的吸收和利用,其中NPF基因家族成员数量众多且功能多样化,近年来获得较多关注和深入研究。模式植物拟南芥和主要粮食作物水稻、玉米和小麦中,分别含有53、93、79和331个NPF基因。拟南芥NPF家族中已有超过一半成员(31/53)的生物学功能被解析,粮食作物水稻中NPF基因功能亦有较多报道。研究表明,NPF基因广泛参与了植物对氮素的吸收及其调控、转运、分配/再分配等过程,一些成员对于改良和提高作物氮素利用率(nitrogen use efficiency,NUE)具有重要作用。因此,从氮素进入植物体及其在植物体内流动的层面出发,发掘具有重要功能的候选NPF基因,对于解析植物利用氮素的分子机制及其遗传改良具有重要意义。本文综述了模式植物拟南芥以及粮食作物中已报道的NPF基因在氮素吸收和利用中的生物学功能。目前粮食作物玉米中仅有4个NPF基因的生物学功能被报道,小麦中尚未有相关报道,未来对玉米和小麦中NPF基因的发掘与功能研究将为改良作物氮素利用效率提供新的基因资源。
基金This work is supported by the National Natural Science Foundation of China(31730076).
文摘The com borer is a world-wide agricultural pest.In this study,a high-efficiency RNAi method was explored to knock down the neuropeptide F(NPF)to determine if NPF regulates larval feeding in the Asian corn borer,Ostrinia furnacalis.Results showed that the expression peaks of npfmRNA in both midgut and fat body are at 28 h of early 5th instar larvae.When NPF was kno eked dow n either by feedi ng dsNPF-c ontaining artificial diet or direct dsNPF in jection into the 5th in star larvae,npf expression was effectively inhibited in the midgut.Larval feeding,body weight and development time were significantly impacted.In con trast,the expressi on of the npf receptors npfrl and npfr2 in fat body of 5th in star larvae was sign ifica ntly increased by dsNPF injection.These results indicate that NPF can be effectively knoeked down in 0.furnacalis,and dsNPF by injection is an effective and fast way to silence npf expression.This study provides a critical basis for further exploration in mechanism of feeding regulation in 0.furnacalis.
基金funded by the National Basic Research Program of China (2005CB422203, 2005CB422208)National Department Public Benefit Research Foundation (No.201009001)National Natural Science Foundation of China(Grant No. 41005065)
文摘Particle number size distribution from 10 to 10,000 nm was measured by a wide-range particle spectrometer (WPS-1000XP) at a downwind site north of downtown Lanzhou, western China, from 25 june to 19 July 2006. We first report the pollution level, diurnal variation of particle concentration in different size ranges and then introduce the characteristics of the particle formation processes, to show that the number concentration of ultrafine particles was lower than the values measured in other urban or suburban areas in previous studies, However, the fraction of ultrafine particles in total aerosol number concentration was found to be much higher. Furthermore, sharp increase of ultrafine particle concentration was frequently observed at noon. An examination of the diurnal pattern suggests that the burst of the ultrafine particles was mainly due to nucleation process. During the 25-day observation, new particle formation (NPF) from homogeneous nucleation was observed during 33% of the study period. The average growth rate of the newly formed particles was 4.4 nm/h, varying from 1.3 to 16,9 nm/h. The needed concentration of condensable vapor was 6.1 × 10^7 cm-3, and its source rate was 1.1× 10^6 cm-3 s 1. Further calculation on the source rate of sulphuric acid vapor indicated that the average participation of sulphuric acid to particle growth rate was 68.3%.
基金This work was supported by the Major Program of Shandong Province Natural Science Foundation(ZR2018ZB0212)the Shandong Province Natural Science Foundation(ZR2020QC036)+1 种基金the National Key R&D Program of China(2018YFD1000704,2018YFD1000700)the Natural Science Foundation of China(grant numbers 31970292,31570271,and 32000225).
文摘Abscisic acid(ABA)transport plays an important role in systemic plant responses to environmental factors.However,it remains largely unclear about the precise regulation of ABA transporters in plants.In this study,we show that the C-terminally encoded peptide receptor 2(CEPR2)directly interacts with the ABA transporter NRT1.2/NPF4.6.Genetic and phenotypic analyses revealed that NRT1.2/NPF4.6 positively regulates ABA response and that NRT1.2/NPF4.6 is epistatically and negatively regulated by CEPR2.Further biochemical assays demonstrated that CEPR2 phosphorylates NRT1.2/NPF4.6 at serine 292 to promote its degradation under normal conditions.However,ABA treatment and non-phosphorylation at serine 292 prevented the degradation of NRT1.2/NPF4.6,indicating that ABA inhibits the phosphorylation of this residue.Transport assays in yeast and Xenopus oocytes revealed that non-phosphorylated NRT1.2/NPF4.6 had high levels of ABA import activity,whereas phosphorylated NRT1.2/NPF4.6 did not import ABA.Analyses of complemented nrt1.2 mutants that mimicked non-phosphorylated and phosphorylated NRT1.2/NPF4.6 confirmed that non-phosphorylated NRT1.2S292A had high stability and ABA import activity in planta.Additional experiments showed that NRT1.2/NPF4.6 was degraded via the 26S proteasome and vacuolar degradation pathways.Furthermore,we found that three E2 ubiquitin-conjugating enzymes,UBC32,UBC33,and UBC34,interact with NRT1.2/NPF4.6 in the endoplasmic reticulum and mediate its ubiquitination.NRT1.2/NPF4.6 is epistatically and negatively regulated by UBC32,UBC33,and UBC34 inplanta.Taken together,these results suggest that the stability and ABA import activity of NRT1.2/NPF4.6 are precisely regulated by its phosphorylation and degradation in response to environmental stress.
基金R&D Program of China(2016YFD0100700)in part by the Ministry of Agriculture of China for Transgenic Research(2016ZX08009003-005-003).
文摘Iron(Fe)transport and reallocation are essential to Fe homeostasis in plants,but it is unclear how Fe homeostasis is regulated,especially under stress.Here we report that NPF5.9 and its close homolog NPF5.8 redundantly regulate Fe transport and reallocation in Arabidopsis.NPF5.9 is highly upregulated in response to Fe deficiency.NPF5.9 expresses preferentially in vasculature tissues and localizes to the trans-Golgi network,and NPF5.8 showed a similar expression pattern.Long-distance Fe transport and allocation into aerial parts was significantly increased in NPF5.9-overexpressing lines.In the double mutant npf5.8 npf5.9,Fe loading in aerial parts and plant growth were decreased,which were partially rescued by Fe supplementation.Further analysis showed that expression of PYE,the negative regulator for Fe homeostasis,and its downstream target NAS4 were significantly altered in the double mutant.NPF5.9 and NPF5.8 were shown to also mediate nitrate uptake and transport,although nitrate and Fe application did not reciprocally affect each other.Our findings uncovered the novel function of NPF5.9 and NPF5.8 in long-distance Fe transport and homeostasis,and further indicated that they possibly mediate nitrate transport and Fe homeostasis independently in Arabidopsis.