BACKGROUND Insulin antibodies(IAs)affect blood glucose control in patients receiving insulin therapy.AIM To investigate the relationship between different hypoglycemic treatments and IAs in patients with type 2 diabet...BACKGROUND Insulin antibodies(IAs)affect blood glucose control in patients receiving insulin therapy.AIM To investigate the relationship between different hypoglycemic treatments and IAs in patients with type 2 diabetes mellitus(T2DM).METHODS This cross-sectional,retrospective study included 1863 patients with T2DM who were receiving exogenous insulin therapy.All patients received stable antidiabetic therapy in the last 3 months and IA levels were measured using an iodine-125 array.RESULTS A total of 1863 patients were enrolled.There were 902(48.4%)patients who had positive IAs(IA level>5%),with a mean IA level of 11.06%(10.39%-11.72%).IA levels were positively correlated with high fasting blood glucose(odds ratio=1.069,P<0.001).The proportion of positive IAs was lowest in patients using glargine only(31.9%)and highest in patients using human insulin only(70.3%),P<0.001.The IA levels in patients using sulfonylureas/glinides(8.3%),metformin(9.6%),and dipeptidyl peptidase-4 inhibitors(8.2%)were all lower than in patients without these drugs(all P<0.05).CONCLUSION Nearly half of patients on insulin therapy have positive IA antibodies,and IA antibody levels are associated with blood glucose control.Insulin glargine and a combination of oral glucose-lowering drugs were correlated with lower IA levels.展开更多
Myricaria laxiflora,which grows along the Yangtze River in China,holds ornamental,ecological,and medicinal value.However,its wild population is threatened and currently designated protected as a national priority.The ...Myricaria laxiflora,which grows along the Yangtze River in China,holds ornamental,ecological,and medicinal value.However,its wild population is threatened and currently designated protected as a national priority.The present research was the first to sequence and assemble M.laxiflora’s mitochondrial genome and examine its structural characteristics and phylogenetic relationships with other sequenced Caryophyllales species.The mitochondrial double-stranded closed-ring genome of M.laxiflora was found to be 389,949 bp in length,containing numerous repetitive sequences and RNA editing sites,with 34 protein encoding,21 tRNA,and 3 rRNA genes.Although there are 22 fragments in the mitochondrial genome of M.laxiflora that are homologous to its chloroplast genome,they are incomplete gene fragments.Phylogenetic analysis demonstrated evolutionary associations with related populations and was in agreement with findings on the chloroplast genome.These findings not only lay a foundation for its preservation but also offer valuable insights for evolutionary analysis and plant breeding research.展开更多
Lithium batteries(LIBs) with low capacity graphite anode(~372 mAh g-1) cannot meet the ever-growing demand for new energy electric vehicles and renewable energy storage.It is essential to replace graphite anode with h...Lithium batteries(LIBs) with low capacity graphite anode(~372 mAh g-1) cannot meet the ever-growing demand for new energy electric vehicles and renewable energy storage.It is essential to replace graphite anode with higher capacity anode materials for high-energy density LIBs.Silicon(Si) is well known to be a possible alternative for graphite anode due to its highest capacity(~4200 mAh g-1).Unfortunately,large volume change during lithiation and delithiation has prevented the Si anode from being commercialized.Metal silicides are a promising type of anode materials which can improve cycling stability via the accommodation of volume change by dispersing Si in the metal inactive/active matrix,while maintain greater capacity than graphite.Here,we present a classification of Si alloying with metals in periodic table of elements,review the available literature on metal silicide anodes to outline the progress in improving and understanding the electrochemical performance of various metal silicides,analyze the challenges that remain in using metal silicides,and offer perspectives regarding their future research and development as anode materials for commercial LIBs application.展开更多
Chloroplasts most likely originated from the endosymbiosis of cyanobacterial ancestors,entering the eukaryotic lineage about 1.0-1.5 billion years ago(Parfrey et al.,2011;Archibald,2015).Consequently,their biogenesis ...Chloroplasts most likely originated from the endosymbiosis of cyanobacterial ancestors,entering the eukaryotic lineage about 1.0-1.5 billion years ago(Parfrey et al.,2011;Archibald,2015).Consequently,their biogenesis depends on genetic information from both the nuclear and chloroplast genomes.Photosynthetic housekeeping genes of core components in photosystemsⅠandⅡ(PSI and PSII)are encoded by the plastid genome。展开更多
Nowadays, application systems in pervasive computing have to be self-adaptive, which means adapting themselves to dynamic environments. Our aim is to enable systematic development of self-adaptive compo-nent-based app...Nowadays, application systems in pervasive computing have to be self-adaptive, which means adapting themselves to dynamic environments. Our aim is to enable systematic development of self-adaptive compo-nent-based applications. The paper first introduces a novel policy based framework for self-adaptive scheme in pervasive computing. Then the proposed policy ontology and policy language are well expressive and eas-ily extensible to support the design of policy which is based on the Separation of Concerns principle. Fur-thermore, the context-driven event channel decouples the communication between the suppliers and con-sumers for asynchronous communication. The proposed framework can provide both a domain-independent and a flexible self-adaptation solution.展开更多
Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most destructive diseases of rice worldwide. The rice-M, oryzae pathosystem has become a model in the study of plant-fungal interactions beca...Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most destructive diseases of rice worldwide. The rice-M, oryzae pathosystem has become a model in the study of plant-fungal interactions because of its scientific advancement and economic importance. Recent studies have identified a number of new pathogen- associated molecular patterns （PAMPs） and effectors from the blast fungus that trigger rice immune responses upon perception. Interaction analyses between avirulence effectors and their cognate resistance proteins have provided new insights into the molecular basis of plant-fungal interactions. In this review, we summarize the recent research on the characterization of those genes in both M. oryzae and rice that are important for the PAMP- and effector-triggered immunity recognition and signaling processes. We also discuss future directions for research that will further our understanding of this pathosystem.展开更多
Amino acids are the building blocks of protein synthesis.They are structural elements and energy sources of cells necessary for normal cell growth,differentiation and function.Amino acid metabolism disorders have been...Amino acids are the building blocks of protein synthesis.They are structural elements and energy sources of cells necessary for normal cell growth,differentiation and function.Amino acid metabolism disorders have been linked with a number of pathological conditions,including metabolic diseases,cardiovascular diseases,immune diseases,and cancer.In the case of tumors,alterations in amino acid metabolism can be used not only as clinical indicators of cancer progression but also as therapeutic strategies.展开更多
Macrocycles are key tools for molecular recognition and self-assembly.However,traditionally prevalent macrocyclic compounds exhibit specific cavities with diameters usually less than 1 nm,limiting their range of appli...Macrocycles are key tools for molecular recognition and self-assembly.However,traditionally prevalent macrocyclic compounds exhibit specific cavities with diameters usually less than 1 nm,limiting their range of applications in supramolecular chemistry.The efficient synthesis of giant macrocycles remains a significant challenge because an increase in the monomer number results in cyclizationentropy loss.In this study,we developed a low-entropy-penalty synthesis strategy for producing giant macrocycles in high yields.In this process,long and rigid monomers possessing two reaction modules were condensed with paraformaldehyde via Friedel–Crafts reaction.A series of giant macrocycles with cavities of sizes ranging from 2.0 to 4.7 nm were successfully synthesized with cyclization yields of up to 72%.Experimental results and theoretical calculations revealed that extending the monomer length rather than increasing the monomer numbers could notably reduce the cyclization-entropy penalty and avoid configuration twists,thereby favoring the formation of giant macrocycles with large cavities.Significantly,the excellent self-assembly capacity of these giant macrocycles promoted their assembly into organogels.The xerogels exhibited enhanced photoluminescence quantum efficiencies of up to 83.1%.Mechanism investigation revealed the excellent assembly capacity originated from the abundantπ–πinteractions sites of the giant macrocycles.The outstanding emission enhancement resulted from the restricted nonradiative decay processes of rotation/vibration and improved radiative decay process of fluorescence.This study provides an effective and general method for achieving giant macrocycles,thereby expanding the supramolecular toolbox for host–vip chemistry and assembly applications.Moreover,the intriguing assembly and photophysical properties demonstrate the feasibility of developing novel and unique properties by expanding the macrocycle size.展开更多
Recently,immune checkpoint inhibitors(ICIs)and poly(ADP-ribose)polymerase inhibitors(PARPi)have played a pivotal role in prolonging the recurrence-free survival of patients with ovarian cancer(OC).1,2 Although PARPi h...Recently,immune checkpoint inhibitors(ICIs)and poly(ADP-ribose)polymerase inhibitors(PARPi)have played a pivotal role in prolonging the recurrence-free survival of patients with ovarian cancer(OC).1,2 Although PARPi have revolutionized the treatment of OC,the absence of reliable predictive biomarkers limits the broad application of ICIs for patients with homologous recombination(HR)deficiency(HRD).3 CXC-chemokine ligand 13(CXCL13)is a cytokine constitutively secreted in the stromal cells of the B-cell region of secondary lymphoid tissue.4 It exclusively binds to the chemokine receptor CXCR5,which is abundantly expressed in subsets of mature circulating B lymphocytes,follicular helper T cells,and skin-derived dendritic cells,and governs the migration of these cells into secondary lymphoid organs in response to the CXCL13 gradient.5 In this study,we aimed to elucidate the role of CXCL13 in shaping the tumor immune microenvironment(TIME)in HR-deficient OC and to explore its relationship with the cGAS-STING signaling pathway.展开更多
Three new chromone derivatives, phomochromenones A-C （1-3）, and one known chaetocyclinone B （4） were obtained from the cultures ofPhomopsis sp. HNY29-2B isolated from the mangrove Acanthus ilicifolius Linn., which...Three new chromone derivatives, phomochromenones A-C （1-3）, and one known chaetocyclinone B （4） were obtained from the cultures ofPhomopsis sp. HNY29-2B isolated from the mangrove Acanthus ilicifolius Linn., which was collected from the South China Sea. Their structures were determined by the analysis of 1D NMR and 2D NMR as well as mass spectroscopic data. The absolute configurations of I and 2 were assigned by quantum chemi- cal calculations of the electronic circular dichroism （ECD） spectra. Compound 3 is the third example of alkaloids possessing the unique chromeno [3,2-c] pyridine nucleus. In the bioactivity assay, compound 4 showed cytotoxicity against human prostate cancer cell lines （PC-3 and DU145 cells） with the IC50 values of 8.13 and 3.59 μmol/L, respectively.展开更多
Network virtualization is recognized as an effective way to overcome the ossification of the Internet. However, the virtual network mapping problem (VNMP) is a critical challenge, focusing on how to map the virtual ne...Network virtualization is recognized as an effective way to overcome the ossification of the Internet. However, the virtual network mapping problem (VNMP) is a critical challenge, focusing on how to map the virtual networks to the substrate network with efficient utilization of infrastructure resources. The problem can be divided into two phases: node mapping phase and link mapping phase. In the node mapping phase, the existing algorithms usually map those virtual nodes with a complete greedy strategy, without considering the topology among these virtual nodes, resulting in too long substrate paths (with multiple hops). Addressing this problem, we propose a topology awareness mapping algorithm, which considers the topology among these virtual nodes. In the link mapping phase, the new algorithm adopts the k-shortest path algorithm. Simulation results show that the new algorithm greatly increases the long-term average revenue, the acceptance ratio, and the long-term revenue-to-cost ratio (R/C).展开更多
Histone lysine methylation is known to be involved in the epigenetic regulation of gene expression in all eukaryotes including plants. Here we show that the rice SDG714 is primarily responsible for dimethylation but n...Histone lysine methylation is known to be involved in the epigenetic regulation of gene expression in all eukaryotes including plants. Here we show that the rice SDG714 is primarily responsible for dimethylation but not trimethylaUon on histone H3K9 in vivo. Overexpression of YFP-SDG714 in Arabidopsis significantly inhibits plant growth and this inhibition is associated with an enhanced level of H3K9 dimethylation. Our microarray results show that many genes essential for the plant growth and development were downregulated in transgenic Arabidopsis plants overexpressing YFP-SDG714. By chromatin immunoprecipitation analysis, we show that YFP-SDG714 is targeted to specific chromatin regions and dimethylate the H3Kg, which is linked with heterochromatinization and the downregulation of genes. Most interestingly, when YFP-SDG714 production is stopped, the inhibited plants can partially restore their growth, suggesting that the perturbation of gene expression caused by YFP-SDG714 is revertible. Taken together, our results point to an important role of SDG714 in H3K9 dimethylation, suppression of gene expression and plant growth, and provide a potential method to regulate gene expression and plant development by an on-off switch of SDG714 expression.展开更多
基金Supported by The National Key R and D Program of China,No.2018YFC1314103The National Natural Science Foundation of China,No.81870563 and No.82270838.
文摘BACKGROUND Insulin antibodies(IAs)affect blood glucose control in patients receiving insulin therapy.AIM To investigate the relationship between different hypoglycemic treatments and IAs in patients with type 2 diabetes mellitus(T2DM).METHODS This cross-sectional,retrospective study included 1863 patients with T2DM who were receiving exogenous insulin therapy.All patients received stable antidiabetic therapy in the last 3 months and IA levels were measured using an iodine-125 array.RESULTS A total of 1863 patients were enrolled.There were 902(48.4%)patients who had positive IAs(IA level>5%),with a mean IA level of 11.06%(10.39%-11.72%).IA levels were positively correlated with high fasting blood glucose(odds ratio=1.069,P<0.001).The proportion of positive IAs was lowest in patients using glargine only(31.9%)and highest in patients using human insulin only(70.3%),P<0.001.The IA levels in patients using sulfonylureas/glinides(8.3%),metformin(9.6%),and dipeptidyl peptidase-4 inhibitors(8.2%)were all lower than in patients without these drugs(all P<0.05).CONCLUSION Nearly half of patients on insulin therapy have positive IA antibodies,and IA antibody levels are associated with blood glucose control.Insulin glargine and a combination of oral glucose-lowering drugs were correlated with lower IA levels.
基金funded by the Youth Project of the Science and Technology Research Program of the Chongqing Education Commission(No.KJQN202303329)supported by the Scientific Research Project of Promoting Forestry Development through Science and Technology in Chongqing(No.YLKYQN2024-3).
文摘Myricaria laxiflora,which grows along the Yangtze River in China,holds ornamental,ecological,and medicinal value.However,its wild population is threatened and currently designated protected as a national priority.The present research was the first to sequence and assemble M.laxiflora’s mitochondrial genome and examine its structural characteristics and phylogenetic relationships with other sequenced Caryophyllales species.The mitochondrial double-stranded closed-ring genome of M.laxiflora was found to be 389,949 bp in length,containing numerous repetitive sequences and RNA editing sites,with 34 protein encoding,21 tRNA,and 3 rRNA genes.Although there are 22 fragments in the mitochondrial genome of M.laxiflora that are homologous to its chloroplast genome,they are incomplete gene fragments.Phylogenetic analysis demonstrated evolutionary associations with related populations and was in agreement with findings on the chloroplast genome.These findings not only lay a foundation for its preservation but also offer valuable insights for evolutionary analysis and plant breeding research.
基金financially supported by the School-Enterprise cooperation Project(RD18200058)the Anhui Natural Science Foundation(No.1908085ME151)+2 种基金the Anhui province high-end talent Grant(DT18100044)the Key Laboratory of Marine Materials and Related Technologies,CAS(2019K07)the National Foreign Expert Introduction Plan Project(G20190219004)。
文摘Lithium batteries(LIBs) with low capacity graphite anode(~372 mAh g-1) cannot meet the ever-growing demand for new energy electric vehicles and renewable energy storage.It is essential to replace graphite anode with higher capacity anode materials for high-energy density LIBs.Silicon(Si) is well known to be a possible alternative for graphite anode due to its highest capacity(~4200 mAh g-1).Unfortunately,large volume change during lithiation and delithiation has prevented the Si anode from being commercialized.Metal silicides are a promising type of anode materials which can improve cycling stability via the accommodation of volume change by dispersing Si in the metal inactive/active matrix,while maintain greater capacity than graphite.Here,we present a classification of Si alloying with metals in periodic table of elements,review the available literature on metal silicide anodes to outline the progress in improving and understanding the electrochemical performance of various metal silicides,analyze the challenges that remain in using metal silicides,and offer perspectives regarding their future research and development as anode materials for commercial LIBs application.
基金supported by the National Natural Science Foundation of China(31671336 and 31972958)the Start-Up Funds for High Level Talents of Qingdao Agricultural University(663-1120001)the First Class Grassland Science Discipline Program of Shandong Province,China。
文摘Chloroplasts most likely originated from the endosymbiosis of cyanobacterial ancestors,entering the eukaryotic lineage about 1.0-1.5 billion years ago(Parfrey et al.,2011;Archibald,2015).Consequently,their biogenesis depends on genetic information from both the nuclear and chloroplast genomes.Photosynthetic housekeeping genes of core components in photosystemsⅠandⅡ(PSI and PSII)are encoded by the plastid genome。
文摘Nowadays, application systems in pervasive computing have to be self-adaptive, which means adapting themselves to dynamic environments. Our aim is to enable systematic development of self-adaptive compo-nent-based applications. The paper first introduces a novel policy based framework for self-adaptive scheme in pervasive computing. Then the proposed policy ontology and policy language are well expressive and eas-ily extensible to support the design of policy which is based on the Separation of Concerns principle. Fur-thermore, the context-driven event channel decouples the communication between the suppliers and con-sumers for asynchronous communication. The proposed framework can provide both a domain-independent and a flexible self-adaptation solution.
基金This work was supported by the US NSF-IOS to G.L.W. （1120949）the National Natural Science Foundation of China to W.D.L. （31272034）+3 种基金 Y.S.N. （31101405） and X.L.W. （31101404） the 973 Project （2012CBl14005） of Ministry of Science and Technology China and the National Transgenic Crop Initiative to G.L.W. （2012ZX08009001） and the Scientific and Technological Innovation Program of Hunan Universities from Hunan Department of Science and Technology and the Program for Innovative Research Team in University from Ministry of Education in China IRT1239） to Z.L.W. No conflict of interest declared.
文摘Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most destructive diseases of rice worldwide. The rice-M, oryzae pathosystem has become a model in the study of plant-fungal interactions because of its scientific advancement and economic importance. Recent studies have identified a number of new pathogen- associated molecular patterns （PAMPs） and effectors from the blast fungus that trigger rice immune responses upon perception. Interaction analyses between avirulence effectors and their cognate resistance proteins have provided new insights into the molecular basis of plant-fungal interactions. In this review, we summarize the recent research on the characterization of those genes in both M. oryzae and rice that are important for the PAMP- and effector-triggered immunity recognition and signaling processes. We also discuss future directions for research that will further our understanding of this pathosystem.
基金The National Natural Science Foundation of China(82073144,J.W.)the Health Commission of Zhejiang Province(JBZX-202004,J.W.)the Huadong Medicine Joint Funds of the Zhejiang Provincial Natural Science Foundation of China(LHDMD22H310005,J.W.).
文摘Amino acids are the building blocks of protein synthesis.They are structural elements and energy sources of cells necessary for normal cell growth,differentiation and function.Amino acid metabolism disorders have been linked with a number of pathological conditions,including metabolic diseases,cardiovascular diseases,immune diseases,and cancer.In the case of tumors,alterations in amino acid metabolism can be used not only as clinical indicators of cancer progression but also as therapeutic strategies.
基金National Natural Science Foundation of China,Grant/Award Numbers:21971192,22201211Open Research Fund of School of Chemistry and Chemical Engineering,Henan Normal UniversityNatural Science Foundation of Tianjin Municipality,Grant/Award Numbers:22JCQNJC00190,23JCZDJC00660。
文摘Macrocycles are key tools for molecular recognition and self-assembly.However,traditionally prevalent macrocyclic compounds exhibit specific cavities with diameters usually less than 1 nm,limiting their range of applications in supramolecular chemistry.The efficient synthesis of giant macrocycles remains a significant challenge because an increase in the monomer number results in cyclizationentropy loss.In this study,we developed a low-entropy-penalty synthesis strategy for producing giant macrocycles in high yields.In this process,long and rigid monomers possessing two reaction modules were condensed with paraformaldehyde via Friedel–Crafts reaction.A series of giant macrocycles with cavities of sizes ranging from 2.0 to 4.7 nm were successfully synthesized with cyclization yields of up to 72%.Experimental results and theoretical calculations revealed that extending the monomer length rather than increasing the monomer numbers could notably reduce the cyclization-entropy penalty and avoid configuration twists,thereby favoring the formation of giant macrocycles with large cavities.Significantly,the excellent self-assembly capacity of these giant macrocycles promoted their assembly into organogels.The xerogels exhibited enhanced photoluminescence quantum efficiencies of up to 83.1%.Mechanism investigation revealed the excellent assembly capacity originated from the abundantπ–πinteractions sites of the giant macrocycles.The outstanding emission enhancement resulted from the restricted nonradiative decay processes of rotation/vibration and improved radiative decay process of fluorescence.This study provides an effective and general method for achieving giant macrocycles,thereby expanding the supramolecular toolbox for host–vip chemistry and assembly applications.Moreover,the intriguing assembly and photophysical properties demonstrate the feasibility of developing novel and unique properties by expanding the macrocycle size.
基金the Beijing Xisike Clinical Oncology Research Foundation(China)(No.Y-zai2022/ms-0126).
文摘Recently,immune checkpoint inhibitors(ICIs)and poly(ADP-ribose)polymerase inhibitors(PARPi)have played a pivotal role in prolonging the recurrence-free survival of patients with ovarian cancer(OC).1,2 Although PARPi have revolutionized the treatment of OC,the absence of reliable predictive biomarkers limits the broad application of ICIs for patients with homologous recombination(HR)deficiency(HRD).3 CXC-chemokine ligand 13(CXCL13)is a cytokine constitutively secreted in the stromal cells of the B-cell region of secondary lymphoid tissue.4 It exclusively binds to the chemokine receptor CXCR5,which is abundantly expressed in subsets of mature circulating B lymphocytes,follicular helper T cells,and skin-derived dendritic cells,and governs the migration of these cells into secondary lymphoid organs in response to the CXCL13 gradient.5 In this study,we aimed to elucidate the role of CXCL13 in shaping the tumor immune microenvironment(TIME)in HR-deficient OC and to explore its relationship with the cGAS-STING signaling pathway.
基金Supporting information for this article is available on the WWW under http：//dx.doi.org/10.1002/cjoc.201700375 or from the author.Acknowledgement We thank the National Natural Science Foundation of China （Nos. 21472251, 41276146）, the Key Project of Natural Science Foundation of Guangdong Province （No. 2016A030311026）, the Science ＆ Technology Plan Project of Guangdong Province of China （Nos. 2013B021100011, 2016A040403091）, the Special Financial Fund of Innovative Development of Marine Economic Demonstration Project （No. GD2012-D01- 001）, the China＇s Marine Commonweal Research Project （No. 201305017）, the Guangzhou Project of Science ＆ Technology Planning （No. 201300000062）, the Fundamental Research Funds for the Central Universities （No. 141gjc16） and the Supercomputing Center of Chinese Academy of Sciences （SCCAS） for generous support.
文摘Three new chromone derivatives, phomochromenones A-C （1-3）, and one known chaetocyclinone B （4） were obtained from the cultures ofPhomopsis sp. HNY29-2B isolated from the mangrove Acanthus ilicifolius Linn., which was collected from the South China Sea. Their structures were determined by the analysis of 1D NMR and 2D NMR as well as mass spectroscopic data. The absolute configurations of I and 2 were assigned by quantum chemi- cal calculations of the electronic circular dichroism （ECD） spectra. Compound 3 is the third example of alkaloids possessing the unique chromeno [3,2-c] pyridine nucleus. In the bioactivity assay, compound 4 showed cytotoxicity against human prostate cancer cell lines （PC-3 and DU145 cells） with the IC50 values of 8.13 and 3.59 μmol/L, respectively.
基金supported by the National Basic Research Program (973) of China (No. 2011CB302601)the National Natural Science Foundation of China (No. 90818028)the National High-Tech R&D Program (863) of China (No. 2007AA010301)
文摘Network virtualization is recognized as an effective way to overcome the ossification of the Internet. However, the virtual network mapping problem (VNMP) is a critical challenge, focusing on how to map the virtual networks to the substrate network with efficient utilization of infrastructure resources. The problem can be divided into two phases: node mapping phase and link mapping phase. In the node mapping phase, the existing algorithms usually map those virtual nodes with a complete greedy strategy, without considering the topology among these virtual nodes, resulting in too long substrate paths (with multiple hops). Addressing this problem, we propose a topology awareness mapping algorithm, which considers the topology among these virtual nodes. In the link mapping phase, the new algorithm adopts the k-shortest path algorithm. Simulation results show that the new algorithm greatly increases the long-term average revenue, the acceptance ratio, and the long-term revenue-to-cost ratio (R/C).
基金supported by the National Natural Science Foundation of China (30800629 and 30628004)the National Talent Training Fund in Basic Research of China (J0630643)+2 种基金Shanghai Educational Development Foundation (2007CG06)the Specialized Research Fund for the Doctoral Program of Higher Education (for the New Teachers)supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Histone lysine methylation is known to be involved in the epigenetic regulation of gene expression in all eukaryotes including plants. Here we show that the rice SDG714 is primarily responsible for dimethylation but not trimethylaUon on histone H3K9 in vivo. Overexpression of YFP-SDG714 in Arabidopsis significantly inhibits plant growth and this inhibition is associated with an enhanced level of H3K9 dimethylation. Our microarray results show that many genes essential for the plant growth and development were downregulated in transgenic Arabidopsis plants overexpressing YFP-SDG714. By chromatin immunoprecipitation analysis, we show that YFP-SDG714 is targeted to specific chromatin regions and dimethylate the H3Kg, which is linked with heterochromatinization and the downregulation of genes. Most interestingly, when YFP-SDG714 production is stopped, the inhibited plants can partially restore their growth, suggesting that the perturbation of gene expression caused by YFP-SDG714 is revertible. Taken together, our results point to an important role of SDG714 in H3K9 dimethylation, suppression of gene expression and plant growth, and provide a potential method to regulate gene expression and plant development by an on-off switch of SDG714 expression.
