Receptor kinases play a pivotal role in detecting environmental signals,and consequently,gene pleiotropy is frequently observed within this family.However,the trade-off in trait expression resulting from gene pleiotro...Receptor kinases play a pivotal role in detecting environmental signals,and consequently,gene pleiotropy is frequently observed within this family.However,the trade-off in trait expression resulting from gene pleiotropy poses a constraint on the utilization of such genes in agricultural breeding.In this study,we identified the receptor kinase gene FERONIA-Like Receptor 13(FLR13)as a pleiotropic gene influencing plant height,tillering,grain yield,and disease resistance.Using promoter editing,we generated novel alleles(FLR13T5T6-1,FLR13T5T6-2)that confer resistance to rice blast and increase per-plant yield.The knockout of the T5T6 segment alleviates the inhibitory effects of two transcription factors,OsGBP1 and OsWRKY53,on FLR13 expression.In summary,our study presents a promising avenue for enhancing the pivotal attributes of receptor-like kinases through a promoter-editing strategy.展开更多
The effects of Mg,La and Ca promoters on primary and secondary CO2 and H2O formation pathways during Fischer-Tropsch synthesis on precipitated Fe/Cu/SiO2 catalysts are investigated.The chemisorbed oxygen atoms in the ...The effects of Mg,La and Ca promoters on primary and secondary CO2 and H2O formation pathways during Fischer-Tropsch synthesis on precipitated Fe/Cu/SiO2 catalysts are investigated.The chemisorbed oxygen atoms in the primary pathway formed in the CO dissociation steps reacted with co-adsorbed hydrogen or carbon monoxide to produce H2O and CO2,respectively.The secondary pathway was the water-gas shift reaction.The results indicated that the CO2 production led to an increase in both primary and secondary pathways,and H2O production decreased when surface basicity of the catalyst increased in the order Ca 〉 Mg 〉 La.展开更多
The gas-phase hydrogenation of furfural to furfuralcohol over Cr-free Cu-based catalysts has attracted increasing attention due to its environmentally friendly nature and mild operating conditions.Although reduced pur...The gas-phase hydrogenation of furfural to furfuralcohol over Cr-free Cu-based catalysts has attracted increasing attention due to its environmentally friendly nature and mild operating conditions.Although reduced pure nano-sized CuO exhibits complete furfural hydrogenation and nearly 100%furfuralcohol selectivity,it suffers from rapid deactivation caused by sintering.In this study,we conducted comparative investigations on the catalytic performance and stability of two Cu-based catalysts:90%CuO-10%SiO_(2) and 90%CuO-5%CaO-5%SiO_(2),in the gas-phase furfural hydrogenation.The reaction is carried out under various conditions,including temperatures ranging from 120 to 170℃,LHSVs of 1 to 2.2 h^(-1),and H_(2) to furfural molar ratios of 3.5 to 12.5.The results indicate that under optimal conditions,the Ca-modified catalyst achieves nearly complete furfural conversion and almost 100%furfuralcohol selectivity for a test duration of 31 h.In contrast,the unmodified catalyst exhibits stable performance for only seven hours despite the similar initial performance.XRD analysis confirms that the gradual deactivation of both catalysts is attributed to the oxidation of reduced metallic Cu sites to Cu oxides.Further characterizations of the two spent catalysts using HRTEM and XPS analyses,along with DFT calculations,suggest that the presence of Ca in Cu lattices prevents the loss of electrons from low-valence Cu sites or the reduced metallic Cu sites,thus inhibiting their oxidation to high-valence Cu oxides.This phenomenon contributes to suppressing the deactivation of Cu-catalysts in the gas-phase furfural hydrogenation process.展开更多
Editor's note: We are sorry that because of the over-crowded space in our last issue, we are delayed in presenting the second part of the report delivered by the CAS President Lu Yongxiang at the 2002 working conf...Editor's note: We are sorry that because of the over-crowded space in our last issue, we are delayed in presenting the second part of the report delivered by the CAS President Lu Yongxiang at the 2002 working conference of CAS. The report appears in two installments in this and the 1st issue of this volume.展开更多
Editor's note: We are sorry that because of the over-crowded space in our last issue, we are delayed in presenting the second part of the report delivered by the CAS President Lu Yongxiang at the 2002 working ... Editor's note: We are sorry that because of the over-crowded space in our last issue, we are delayed in presenting the second part of the report delivered by the CAS President Lu Yongxiang at the 2002 working conference of CAS. The report appears in two installments in this and the 1st issue of this volume. ……展开更多
Development of tools for targeted modifications of specific DNA sequences in plants is of great importance to basic plant biology research as well as crop improvement.The ability to cut DNA at specific locations in th...Development of tools for targeted modifications of specific DNA sequences in plants is of great importance to basic plant biology research as well as crop improvement.The ability to cut DNA at specific locations in the genome to generate doublestrand breaks(DSBs)in vivo is a prerequisite for any genome editing efforts.展开更多
CRISPR-Cas9 system is now widely used to edit a target genome in animals and plants. Cas9 protein derived from Streptococcus pyogenes(Sp Cas9) cleaves double-stranded DNA targeted by a chimeric single-guide RNA(sg ...CRISPR-Cas9 system is now widely used to edit a target genome in animals and plants. Cas9 protein derived from Streptococcus pyogenes(Sp Cas9) cleaves double-stranded DNA targeted by a chimeric single-guide RNA(sg RNA). For plant genome editing, Agrobacterium-mediated T-DNA transformation has been broadly used to express Cas9 proteins and sg RNAs under the control of Ca MV 35 S and U6/U3 promoter, respectively. We here developed a simple and high-throughput binary vector system to clone a 19 20 bp of sg RNA, which binds to the reverse complement of a target locus, in a large T-DNA binary vector containing an Sp Cas9 expressing cassette. Twostep cloning procedures:(1) annealing two target-specific oligonucleotides with overhangs specific to the Aar I restriction enzyme site of the binary vector; and(2) ligating the annealed oligonucleotides into the two Aar I sites of the vector, facilitate the high-throughput production of the positive clones. In addition, Cas9-coding sequence and U6/U3 promoter can be easily exchanged via the GatewayTMsystem and unique Eco RI/Xho I sites on the vector, respectively. We examined the mutation ratio and patterns when we transformed these constructs into Arabidopsis thaliana and a wild tobacco, Nicotiana attenuata. Our vector system will be useful to generate targeted large-scale knock-out lines of model as well as non-model plant.展开更多
基金supported by the National Natural Science Foundation of China (NSFC-32201712,32470328)the Science and Technology Innovation Program of Hunan Province (2021JJ10015,2023JJ10025)the National Key Research and Development Program of China (2023YFD1401100).
文摘Receptor kinases play a pivotal role in detecting environmental signals,and consequently,gene pleiotropy is frequently observed within this family.However,the trade-off in trait expression resulting from gene pleiotropy poses a constraint on the utilization of such genes in agricultural breeding.In this study,we identified the receptor kinase gene FERONIA-Like Receptor 13(FLR13)as a pleiotropic gene influencing plant height,tillering,grain yield,and disease resistance.Using promoter editing,we generated novel alleles(FLR13T5T6-1,FLR13T5T6-2)that confer resistance to rice blast and increase per-plant yield.The knockout of the T5T6 segment alleviates the inhibitory effects of two transcription factors,OsGBP1 and OsWRKY53,on FLR13 expression.In summary,our study presents a promising avenue for enhancing the pivotal attributes of receptor-like kinases through a promoter-editing strategy.
文摘The effects of Mg,La and Ca promoters on primary and secondary CO2 and H2O formation pathways during Fischer-Tropsch synthesis on precipitated Fe/Cu/SiO2 catalysts are investigated.The chemisorbed oxygen atoms in the primary pathway formed in the CO dissociation steps reacted with co-adsorbed hydrogen or carbon monoxide to produce H2O and CO2,respectively.The secondary pathway was the water-gas shift reaction.The results indicated that the CO2 production led to an increase in both primary and secondary pathways,and H2O production decreased when surface basicity of the catalyst increased in the order Ca 〉 Mg 〉 La.
基金financially supported by Youth Fund of National Natural Science Foundation of China(NO.22108175)National Natural Science Foundation of China(U190310)+3 种基金Natural Science Foundation of Liaoning province(2021-NLTS-12-09)Liaoning Innovation Talents Program in University(Liao[2020]389)Liaoning Revitalization Talents Program(XLYC1907029)Shenyang Young and Middle-aged Science&Technology Talents Program(RC210365).
文摘The gas-phase hydrogenation of furfural to furfuralcohol over Cr-free Cu-based catalysts has attracted increasing attention due to its environmentally friendly nature and mild operating conditions.Although reduced pure nano-sized CuO exhibits complete furfural hydrogenation and nearly 100%furfuralcohol selectivity,it suffers from rapid deactivation caused by sintering.In this study,we conducted comparative investigations on the catalytic performance and stability of two Cu-based catalysts:90%CuO-10%SiO_(2) and 90%CuO-5%CaO-5%SiO_(2),in the gas-phase furfural hydrogenation.The reaction is carried out under various conditions,including temperatures ranging from 120 to 170℃,LHSVs of 1 to 2.2 h^(-1),and H_(2) to furfural molar ratios of 3.5 to 12.5.The results indicate that under optimal conditions,the Ca-modified catalyst achieves nearly complete furfural conversion and almost 100%furfuralcohol selectivity for a test duration of 31 h.In contrast,the unmodified catalyst exhibits stable performance for only seven hours despite the similar initial performance.XRD analysis confirms that the gradual deactivation of both catalysts is attributed to the oxidation of reduced metallic Cu sites to Cu oxides.Further characterizations of the two spent catalysts using HRTEM and XPS analyses,along with DFT calculations,suggest that the presence of Ca in Cu lattices prevents the loss of electrons from low-valence Cu sites or the reduced metallic Cu sites,thus inhibiting their oxidation to high-valence Cu oxides.This phenomenon contributes to suppressing the deactivation of Cu-catalysts in the gas-phase furfural hydrogenation process.
文摘Editor's note: We are sorry that because of the over-crowded space in our last issue, we are delayed in presenting the second part of the report delivered by the CAS President Lu Yongxiang at the 2002 working conference of CAS. The report appears in two installments in this and the 1st issue of this volume.
文摘 Editor's note: We are sorry that because of the over-crowded space in our last issue, we are delayed in presenting the second part of the report delivered by the CAS President Lu Yongxiang at the 2002 working conference of CAS. The report appears in two installments in this and the 1st issue of this volume. ……
基金supported by a National Transgenic Science and Technology Program (2016ZX08010002)to R.W.a startup fund from the Huazhong Agricultural University
文摘Development of tools for targeted modifications of specific DNA sequences in plants is of great importance to basic plant biology research as well as crop improvement.The ability to cut DNA at specific locations in the genome to generate doublestrand breaks(DSBs)in vivo is a prerequisite for any genome editing efforts.
基金supported by Institute for Basic Science (IBS-R021-D1)
文摘CRISPR-Cas9 system is now widely used to edit a target genome in animals and plants. Cas9 protein derived from Streptococcus pyogenes(Sp Cas9) cleaves double-stranded DNA targeted by a chimeric single-guide RNA(sg RNA). For plant genome editing, Agrobacterium-mediated T-DNA transformation has been broadly used to express Cas9 proteins and sg RNAs under the control of Ca MV 35 S and U6/U3 promoter, respectively. We here developed a simple and high-throughput binary vector system to clone a 19 20 bp of sg RNA, which binds to the reverse complement of a target locus, in a large T-DNA binary vector containing an Sp Cas9 expressing cassette. Twostep cloning procedures:(1) annealing two target-specific oligonucleotides with overhangs specific to the Aar I restriction enzyme site of the binary vector; and(2) ligating the annealed oligonucleotides into the two Aar I sites of the vector, facilitate the high-throughput production of the positive clones. In addition, Cas9-coding sequence and U6/U3 promoter can be easily exchanged via the GatewayTMsystem and unique Eco RI/Xho I sites on the vector, respectively. We examined the mutation ratio and patterns when we transformed these constructs into Arabidopsis thaliana and a wild tobacco, Nicotiana attenuata. Our vector system will be useful to generate targeted large-scale knock-out lines of model as well as non-model plant.