An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting usi...An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting using special probe demonstrated that there existed one copy of Lhcb 2 in pea genome. RT_PCR and Northern blotting revealed the expression of Lhcb 2 which was regulated by light in a time_dependent expression manner. The Lhcb 2 gene didn't express untill 2 h after irradiated with white light. Low temperature (4 ℃) also affected the Lhcb 2 gene by decreasing half of its expression under 25 ℃.展开更多
Heavy flavour physics provides excellent opportunities to indirectly search for new physics at very high energy scales and to study hadron properties for deep understanding of the strong interaction.The LHCb experimen...Heavy flavour physics provides excellent opportunities to indirectly search for new physics at very high energy scales and to study hadron properties for deep understanding of the strong interaction.The LHCb experiment has been playing a leading role in the study of heavy flavour physics since the start of the LHC operations about ten years ago,and made a range of high-precision measurements and unexpected discoveries,which may have far-reaching implications on the field of particle physics.This review highlights a selection of the most influential physics results on CP violation,rare decays,and heavy flavour production and spectroscopy obtained by LHCb using the data collected during the first two operation periods of the LHC.The upgrade plan of LHCb and the physics prospects are also briefly discussed.展开更多
In 1964, Murray Gell-Mann [1], the Nobel Prize winner in Physics, and George Zweig [2] separately proposed the quark model.The model revealed for the first time that a class of particles, baryons including protons and...In 1964, Murray Gell-Mann [1], the Nobel Prize winner in Physics, and George Zweig [2] separately proposed the quark model.The model revealed for the first time that a class of particles, baryons including protons and neutrons, were not elementary, instead were formed by three quarks (qqq), and another class, mesons,were made of quark-antiquark pairs (qqà). The quark model can successfully describe all the baryons and mesons (collectively referred to as hadrons) observed in the last century, thereby helps to explain how the strong force binds the quarks to form a particle.展开更多
We study the potential of the LHCb 13 TeV single W±and Z boson pseudo-data for constraining the parton distribution functions(PDFs)of the proton.As an example,we demonstrate the sensitivity of the LHCb 13 TeV dat...We study the potential of the LHCb 13 TeV single W±and Z boson pseudo-data for constraining the parton distribution functions(PDFs)of the proton.As an example,we demonstrate the sensitivity of the LHCb 13 TeV data,collected with integrated luminosities of 5fb^(-1) and 300 fb^(-1) ,to reducing the PDF uncertainty bands of the CT14HERA2 PDFs,using the error PDF updating package EPUMP.The sensitivities of various experimental observables are compared.Generally,sizable reductions in PDF uncertainties can be observed in the 300fb^(-1) data sample,particularly in the small-x region.The double-differential cross section measurement of Z boson pT and rapidity can greatly reduce the uncertainty bands of u and d quarks in almost the whole x range,as compared to various single observable measurements.展开更多
Lhcb2 gene from pea (Pisum sativum L.) was subcloned into bacterial expression vector pET-3d, and its protein overexpressed was obtained from E. coli (BL21) containing PetpLhcb2 by site-directed mutagenesis method. Ba...Lhcb2 gene from pea (Pisum sativum L.) was subcloned into bacterial expression vector pET-3d, and its protein overexpressed was obtained from E. coli (BL21) containing PetpLhcb2 by site-directed mutagenesis method. Bacteria transformed with this construct yielded up to 40 percent of total protein of E. coli. Using the modified method with three subsequent cycles of freezing (1 min, -196℃) and thawing (15 min, 25℃), Lhcb2 protein purified was highly reconstituted with pigments to yield pigment-protein complexes. The reconstituted LHCB2 monomers were very similar to native LHCll monomers from spinach in partially denaturing polyacrylamide gel electrophoresis, fluorescence and absorbance spectroscopy. These results showed that Lhcb2 proteins overexpressed were reconstituted successfully with pigments and had similar organization and structure to the native LHCII monomers.展开更多
Recently the LHCb Collaboration [1] published the results of a search for the doubly charmed baryon ■. No significant signal is seen in the mass range from 3.4 to3.8 Ge V. To put this result in context, the ■baryon ...Recently the LHCb Collaboration [1] published the results of a search for the doubly charmed baryon ■. No significant signal is seen in the mass range from 3.4 to3.8 Ge V. To put this result in context, the ■baryon was seen by LHCb in decay modes ΛcK-π^+π^+[2](2017) and ■^+cπ^+[3](2018). The weighted average of the ■^++cc mass is 3621.24±0.65 (stat.)±0.31 (syst.) MeV [3].展开更多
Photosynthesis is the fundamental basis of plant growth and development,and the improvement of photosynthetic efficiency can therefore promote increased crop yields.In this study,a comparative analysis of photosynthet...Photosynthesis is the fundamental basis of plant growth and development,and the improvement of photosynthetic efficiency can therefore promote increased crop yields.In this study,a comparative analysis of photosynthetic physiology and transcriptome was conducted between the high photosynthetic efficient variety BN207 and its parents BN64 and ZM16.The higher chlorophyll fluorescence,chlorophyll and carotenoid contents,and Lhcb1 protein accumulation in BN207 improved photosynthetic efficiency by promoting light energy absorption and conversion.Chloroplasts being distributed more closely to the cell membrane and the higher Rubisco enzyme activity of BN207 enhanced carbon assimilation,resulting in more carbohydrate accumulation in BN207.Transcriptome analysis revealed that there were several key genes mediating the high photosynthetic efficiency of BN207:Traes CS5 D02 G364100(chlorophyllase),BGI_novel_G006617(lycopeneε-cyclase),Traes CS4 A02 G034800 and Traes CS4 A02 G035100(Zeaxanthin epoxidase),Traes CS6 B02 G122500(light-harvesting complex II chlorophyll a/b binding protein 1).These genes improved the photosynthetic efficiency of BN207 mainly by reducing chlorophyll degradation,promoting carotenoid synthesis,and increasing Lhcb1 protein accumulation.These findings provide important background information for the cultivation of wheat varieties with high photosynthetic efficiency.展开更多
Photosynthesis includes the collection of light and a/b-binding （LHC） proteins. In high plants, the LHC gene family constituting the light-harvesting complex ofphotosystems I and II. the transfer of solar energy usi...Photosynthesis includes the collection of light and a/b-binding （LHC） proteins. In high plants, the LHC gene family constituting the light-harvesting complex ofphotosystems I and II. the transfer of solar energy using light-harvesting chlorophyll includes LHCA and LHCB sub-families, which encode proteins Zostera marina L. is a monocotyledonous angiosperm and inhab- its submerged marine environments rather than land environments. We characterized the Lhca and Lhcb gene families of Z. marina from the expressed sequence tags （EST） database. In total, 13 unigenes were annotated as ZmLhc, 6 in Lhca family and 7 in ZmLhcb family. ZmLHCA and ZmLHCB contained the conservative LHC motifs and amino acid residues binding chlorophyll. The average similarity among mature ZmLHCA and ZmLHCB was 48.91% and 48.66%, respectively, which indicated a high degree of diver- gence within ZmLHChc gene family. The reconstructed phylogenetic tree showed that the tree topology and phylogenetic relation- ship were similar to those reported in other high plants, suggesting that the Lhc genes were highly conservative and the classification of ZmLhc genes was consistent with the evolutionary position of Z. marina. Real-time reverse transcription （RT） PCR analysis showed that different members of ZmLhca and ZmLhcb responded to a stress in different expression patterns. Salinity, temperature, light intensity and light quality may affect the expression of most ZmLhca and ZmLhcb genes. Inorganic carbon concentration and acidity had no obvious effect on ZmLhca and ZmLhcb gene expression, except for ZmLhca6.展开更多
Photosynthetic efficiency is the primary determinant of crop yield,including vegetative biomass and grain yield.Manipulation of key transcription factors known to directly control photosynthetic machinery can be an ef...Photosynthetic efficiency is the primary determinant of crop yield,including vegetative biomass and grain yield.Manipulation of key transcription factors known to directly control photosynthetic machinery can be an effective strategy to improve photosynthetic traits.In this study,we identified an Arabidopsis gain-of-function mutant,cogwheel1-3D,that shows a significantly enlarged rosette and increased biomass compared with wild-type plants.Overexpression of COG1,a Dof transcription factor,recapitulated the phenotype of cogwheel1-3D,whereas knocking out COG1 and its six paralogs resulted in a reduced rosette size and decreased biomass.Transcriptomic and quantitative reverse transcription polymerase chain reaction analyses demonstrated that COG1 and its paralogs were required for light-induced expression of genes involved in photosynthesis.Further chromatin immunoprecipitation and electrophoretic mobility shift assays indicated that COG1 can directly bind to the promoter regions of multiple genes encoding light-harvesting antenna proteins.Physiological,biochemical,and microscopy analyses revealed that COG1 enhances photosynthetic capacity and starch accumulation in Arabidopsis rosette leaves.Furthermore,combined results of bioinformatic,genetic,and molecular experiments suggested that the functions of COG1 in increasing biomass are conserved in different plant species.These results collectively demonstrated that COG1 acts as a key regulator of plant biomass by promoting photosynthesis and starch accumulation.Manipulating COG1 to optimize photosynthetic capacity would create new strategies for future crop yield improvement.展开更多
文摘An approximately 800 bp cDNA ( Lhcb 2) encoding light_harvesting chlorophyll a/b_binding protein complex (type Ⅱ) was cloned from the seedling of pea ( Pisum sativum L.) with RT_PCR method. Southern blotting using special probe demonstrated that there existed one copy of Lhcb 2 in pea genome. RT_PCR and Northern blotting revealed the expression of Lhcb 2 which was regulated by light in a time_dependent expression manner. The Lhcb 2 gene didn't express untill 2 h after irradiated with white light. Low temperature (4 ℃) also affected the Lhcb 2 gene by decreasing half of its expression under 25 ℃.
基金supported by the National Key Research and Development Program of China under Grant Nos.2017YFA0402100 and 2022YFA1601900the National Natural Science Foundation of China(NSFC)under Grant Nos.11435003,11575091,11575094,11925504,11975015,12175245,12175005,11705209,12205312,12275100,11961141015 and 12061141007Chinese Academy of Sciences,Fundamental Research Funds for the Central Universities,Peking University Funds for the New Faculty Startup program.We thank Franz Muheim and Niels Tuning for suggestions in improving the draft.
文摘Heavy flavour physics provides excellent opportunities to indirectly search for new physics at very high energy scales and to study hadron properties for deep understanding of the strong interaction.The LHCb experiment has been playing a leading role in the study of heavy flavour physics since the start of the LHC operations about ten years ago,and made a range of high-precision measurements and unexpected discoveries,which may have far-reaching implications on the field of particle physics.This review highlights a selection of the most influential physics results on CP violation,rare decays,and heavy flavour production and spectroscopy obtained by LHCb using the data collected during the first two operation periods of the LHC.The upgrade plan of LHCb and the physics prospects are also briefly discussed.
基金supported by Ministry of Science and Technology of the People’s Republic of China (2017YFA0402103)the National Natural Science Foundation of China (11775122)supported by the National Science Foundation (USA) Award Number 1803004
文摘In 1964, Murray Gell-Mann [1], the Nobel Prize winner in Physics, and George Zweig [2] separately proposed the quark model.The model revealed for the first time that a class of particles, baryons including protons and neutrons, were not elementary, instead were formed by three quarks (qqq), and another class, mesons,were made of quark-antiquark pairs (qqà). The quark model can successfully describe all the baryons and mesons (collectively referred to as hadrons) observed in the last century, thereby helps to explain how the strong force binds the quarks to form a particle.
基金Supported by the National Natural Science Foundation of China(11875142,11965020)the U.S.National Science Foundation(PHY-2013791.C-P)。
文摘We study the potential of the LHCb 13 TeV single W±and Z boson pseudo-data for constraining the parton distribution functions(PDFs)of the proton.As an example,we demonstrate the sensitivity of the LHCb 13 TeV data,collected with integrated luminosities of 5fb^(-1) and 300 fb^(-1) ,to reducing the PDF uncertainty bands of the CT14HERA2 PDFs,using the error PDF updating package EPUMP.The sensitivities of various experimental observables are compared.Generally,sizable reductions in PDF uncertainties can be observed in the 300fb^(-1) data sample,particularly in the small-x region.The double-differential cross section measurement of Z boson pT and rapidity can greatly reduce the uncertainty bands of u and d quarks in almost the whole x range,as compared to various single observable measurements.
文摘Lhcb2 gene from pea (Pisum sativum L.) was subcloned into bacterial expression vector pET-3d, and its protein overexpressed was obtained from E. coli (BL21) containing PetpLhcb2 by site-directed mutagenesis method. Bacteria transformed with this construct yielded up to 40 percent of total protein of E. coli. Using the modified method with three subsequent cycles of freezing (1 min, -196℃) and thawing (15 min, 25℃), Lhcb2 protein purified was highly reconstituted with pigments to yield pigment-protein complexes. The reconstituted LHCB2 monomers were very similar to native LHCll monomers from spinach in partially denaturing polyacrylamide gel electrophoresis, fluorescence and absorbance spectroscopy. These results showed that Lhcb2 proteins overexpressed were reconstituted successfully with pigments and had similar organization and structure to the native LHCII monomers.
文摘Recently the LHCb Collaboration [1] published the results of a search for the doubly charmed baryon ■. No significant signal is seen in the mass range from 3.4 to3.8 Ge V. To put this result in context, the ■baryon was seen by LHCb in decay modes ΛcK-π^+π^+[2](2017) and ■^+cπ^+[3](2018). The weighted average of the ■^++cc mass is 3621.24±0.65 (stat.)±0.31 (syst.) MeV [3].
基金supported by the National Key Research and Development Program of China(2017YFD0300408)。
文摘Photosynthesis is the fundamental basis of plant growth and development,and the improvement of photosynthetic efficiency can therefore promote increased crop yields.In this study,a comparative analysis of photosynthetic physiology and transcriptome was conducted between the high photosynthetic efficient variety BN207 and its parents BN64 and ZM16.The higher chlorophyll fluorescence,chlorophyll and carotenoid contents,and Lhcb1 protein accumulation in BN207 improved photosynthetic efficiency by promoting light energy absorption and conversion.Chloroplasts being distributed more closely to the cell membrane and the higher Rubisco enzyme activity of BN207 enhanced carbon assimilation,resulting in more carbohydrate accumulation in BN207.Transcriptome analysis revealed that there were several key genes mediating the high photosynthetic efficiency of BN207:Traes CS5 D02 G364100(chlorophyllase),BGI_novel_G006617(lycopeneε-cyclase),Traes CS4 A02 G034800 and Traes CS4 A02 G035100(Zeaxanthin epoxidase),Traes CS6 B02 G122500(light-harvesting complex II chlorophyll a/b binding protein 1).These genes improved the photosynthetic efficiency of BN207 mainly by reducing chlorophyll degradation,promoting carotenoid synthesis,and increasing Lhcb1 protein accumulation.These findings provide important background information for the cultivation of wheat varieties with high photosynthetic efficiency.
基金supported by the Key Science and Technology Program of Shandong Province (Grant no.2012GHY11527)the Public Science and Technology Research Funds Projects of Ocean,State Oceanic Administration of China (Grant no.201105021)
文摘Photosynthesis includes the collection of light and a/b-binding （LHC） proteins. In high plants, the LHC gene family constituting the light-harvesting complex ofphotosystems I and II. the transfer of solar energy using light-harvesting chlorophyll includes LHCA and LHCB sub-families, which encode proteins Zostera marina L. is a monocotyledonous angiosperm and inhab- its submerged marine environments rather than land environments. We characterized the Lhca and Lhcb gene families of Z. marina from the expressed sequence tags （EST） database. In total, 13 unigenes were annotated as ZmLhc, 6 in Lhca family and 7 in ZmLhcb family. ZmLHCA and ZmLHCB contained the conservative LHC motifs and amino acid residues binding chlorophyll. The average similarity among mature ZmLHCA and ZmLHCB was 48.91% and 48.66%, respectively, which indicated a high degree of diver- gence within ZmLHChc gene family. The reconstructed phylogenetic tree showed that the tree topology and phylogenetic relation- ship were similar to those reported in other high plants, suggesting that the Lhc genes were highly conservative and the classification of ZmLhc genes was consistent with the evolutionary position of Z. marina. Real-time reverse transcription （RT） PCR analysis showed that different members of ZmLhca and ZmLhcb responded to a stress in different expression patterns. Salinity, temperature, light intensity and light quality may affect the expression of most ZmLhca and ZmLhcb genes. Inorganic carbon concentration and acidity had no obvious effect on ZmLhca and ZmLhcb gene expression, except for ZmLhca6.
基金supported in part by the National Natural Science Foundation of China(32270341,31700245,and 32030005)the Natural Science Foundation for Distinguished Young Scholars of Gansu Province(20JR5RA306)+2 种基金the Postdoctoral Research Foundation of China(2018T111116 and 2016M602889)the Programme of Introducing Talents of Discipline to Universities(B16022)the Fundamental Research Funds for the Central Universities(lzujbky-2020-32 and lzujbky-2022-kb03).
文摘Photosynthetic efficiency is the primary determinant of crop yield,including vegetative biomass and grain yield.Manipulation of key transcription factors known to directly control photosynthetic machinery can be an effective strategy to improve photosynthetic traits.In this study,we identified an Arabidopsis gain-of-function mutant,cogwheel1-3D,that shows a significantly enlarged rosette and increased biomass compared with wild-type plants.Overexpression of COG1,a Dof transcription factor,recapitulated the phenotype of cogwheel1-3D,whereas knocking out COG1 and its six paralogs resulted in a reduced rosette size and decreased biomass.Transcriptomic and quantitative reverse transcription polymerase chain reaction analyses demonstrated that COG1 and its paralogs were required for light-induced expression of genes involved in photosynthesis.Further chromatin immunoprecipitation and electrophoretic mobility shift assays indicated that COG1 can directly bind to the promoter regions of multiple genes encoding light-harvesting antenna proteins.Physiological,biochemical,and microscopy analyses revealed that COG1 enhances photosynthetic capacity and starch accumulation in Arabidopsis rosette leaves.Furthermore,combined results of bioinformatic,genetic,and molecular experiments suggested that the functions of COG1 in increasing biomass are conserved in different plant species.These results collectively demonstrated that COG1 acts as a key regulator of plant biomass by promoting photosynthesis and starch accumulation.Manipulating COG1 to optimize photosynthetic capacity would create new strategies for future crop yield improvement.
