Dihydroorotate dehydrogenase(DHODH)is a central enzyme of the de novo pyrimidine biosynthesis pathway and is a promising drug target for the treatment of cancer and autoimmune diseases.This study presents the identifi...Dihydroorotate dehydrogenase(DHODH)is a central enzyme of the de novo pyrimidine biosynthesis pathway and is a promising drug target for the treatment of cancer and autoimmune diseases.This study presents the identification of a potent DHODH inhibitor by proteomic profiling.Cell-based screening revealed that NPD723,which is reduced to H-006 in cells,strongly induces myeloid differentiation and inhibits cell growth in HL-60 cells.H-006 also suppressed the growth of various cancer cells.Proteomic profiling of NPD723-treated cells in ChemProteoBase showed that NPD723 was clustered with DHODH inhibitors.H-006 potently inhibited human DHODH activity in vitro,whereas NPD723 was approximately 400 times less active than H-006.H-006-induced cell death was rescued by the addition of the DHODH product orotic acid.Moreover,metabolome analysis revealed that H-006 treatment promotes marked accumulation of the DHODH substrate dihydroorotic acid.These results suggest that NPD723 is reduced in cells to its active metabolite H-006,which then targets DHODH and suppresses cancer cell growth.Thus,H-006-related drugs represent a potentially powerful treatment for cancer and other diseases.展开更多
Seeking and developing efficient CO_(2)reduction reaction(CO_(2)RR)electrocatalysts is a hot topic in this era of global warming.Among material candidates for sustainable and cost-effective applications,metal sulfides...Seeking and developing efficient CO_(2)reduction reaction(CO_(2)RR)electrocatalysts is a hot topic in this era of global warming.Among material candidates for sustainable and cost-effective applications,metal sulfides have attracted attention as promising nature-inspired materials due to multiple adsorption sites which are enhanced by the covalent character of sulfur.This article summarizes the current status regarding the utilization and development of metal sulfide materials as CO_(2)RR electrocatalysts.First,the research background and basic principles of electrochemical CO_(2)RR are introduced.Next,an overview of the main obstacles to developing efficient CO_(2)RR electrocatalysts is presented.The section is followed by a summary of the empirical evidence supporting the application of metal sulfides as CO_(2)RR electrocatalysts beside nature-inspired motivation.The summary of synthesis methods of various metal sulfides is also presented.Furthermore,the paper also highlights the recent works on metal sulfide as efficient CO_(2)RR including the undertaking strategy on the activity enhancement,and finally,discusses the challenges and prospect of metal sulfides-based CO_(2)RR electrocatalysts.Despite recent efforts,metal sulfides remain relatively unexplored as materials for CO_(2)RR electrocatalytic applications.Therefore,this review aims to stimulate novel ideas and research for improved catalyst designs and functionality.展开更多
Molybdenum sulfides are promising electrocatalysts for the hydrogen evolution reaction(HER).Sand Mo‐related species have been proposed as the active site for forming adsorbed hydrogen to initiate the HER;however,the ...Molybdenum sulfides are promising electrocatalysts for the hydrogen evolution reaction(HER).Sand Mo‐related species have been proposed as the active site for forming adsorbed hydrogen to initiate the HER;however,the nature of the interaction between Mo centers and S ligands is unclear.Further,the development of cost‐effective water‐splitting systems using neutral water as a proton source for H2evolution is highly desirable,whereas the mechanism of the HER at neutral pH is rarely discussed.Here,the structural change in the Mo?Mo and S?S species in a synthesized molybdenum sulfide was monitored at neutral pH using in situ electrochemical Raman spectroscopy.Analysis of the potential dependent Raman spectra revealed that the band assigned to a terminal S?S species emerged along with synchronized changes in the frequency of the Mo?Mo,Mo3?μ3S,and Mo?S vibrational bands.This indicates that Mo?Mo bonds and terminal S?S ligands play synergistic roles in facilitating hydrogen evolution,likely via the internal reorganization of trinuclear Mo3?thio species.The nature and role of metal‐ligand interactions in the HER revealed in this study demonstrated a mechanism that is distinct from those reported previously in which the S or Mo sites function independently.展开更多
Abiotic stress confers serious damage to the photosynthetic machinery,often resulting in plant growth inhibition.Hypothetical chloroplast open reading frame 3(Ycf3)-interacting protein 1(Y3IP1)is a nucleus-encoded thy...Abiotic stress confers serious damage to the photosynthetic machinery,often resulting in plant growth inhibition.Hypothetical chloroplast open reading frame 3(Ycf3)-interacting protein 1(Y3IP1)is a nucleus-encoded thylakoid protein and plays an essential role in the assembly of photosystem I.The full-length cDNA over-expresser(FOX)gene-hunting system is an approach using systemically generated gain-of-function mutants.Among the FOX-rice lines,a line CE175 overexpressing rice Y3IP1gene(Os Y3IP1)displayed less inhibition of root growth under saline(NaCl)stress.The expression of Os Y3IP1 was up-regulated under saline and alkaline(Na2CO3)stresses in the rice variety Kitaake.After saline and alkaline treatments,transgenic Kitaake overexpressing OsY3IP1-GFP(OsY3IP1-GFPox/Kit)displayed higher levels of chlorophyll content compared to Kitaake.Under the stress conditions,the maximum quantum yield of photosystem II photochemistry levels was higher in OsY3IP1-GFPox/Kit than in Kitaake.The increased tolerance conferred by OsY3IP1 overexpression correlated with reduced reactive oxygen species accumulation.Our data provide new insights into the possible role of OsY3IP1 in the pathway suppressing photooxidative damage under stress conditions.These features can be further exploited to improve saline and alkaline tolerances of rice plants in future.展开更多
Population genetics studies of allopolyploid species lag behind those of diploid species because of practical difficulties in analysis of homeologs-duplicated gene copies originating from hybridized parental species. ...Population genetics studies of allopolyploid species lag behind those of diploid species because of practical difficulties in analysis of homeologs-duplicated gene copies originating from hybridized parental species. Pool-Seq, i.e. massive parallel sequencing of pooled individuals, has high potential for detecting nucleotide polymorphisms within and among multiple populations;however, its use has been limited to diploid species. We applied Pool-Seq to an allopolyploid species by developing a bioinformatic pipeline that assigns reads to each homeolog as well as to each polymorphic allele within each homeolog. We simultaneously sequenced eight genes from twenty individuals from each of 24 populations, and found over 100 polymorphic sites in each homeolog. For two sites, we estimated allele frequencies using the number of reads and then validated these estimations by making individual-based estimations. Pool-Seq using our bioinformatic pipeline allows efficient evaluation of nucleotide polymorphisms in a large number of individuals, even in allopolyploid species.展开更多
Indole-3-acetamide(IAM)is the first confirmed auxin biosynthetic intermediate in some plant pathogenic bacteria.Exogenously applied IAM or production of IAM by overexpressing the bacterial iaaM gene in Arabidopsis cau...Indole-3-acetamide(IAM)is the first confirmed auxin biosynthetic intermediate in some plant pathogenic bacteria.Exogenously applied IAM or production of IAM by overexpressing the bacterial iaaM gene in Arabidopsis causes auxin overproduction phenotypes.However,it is still inconclusive whether plants use IAM as a key precursor for auxin biosynthesis.Herein,we reported the isolation IAM HYDROLASE 1(IAMH1)gene in Arabidopsis from a forward genetic screen for IAM-insensitive mutants that display normal auxin sensitivities.IAMH1 has a close homolog named IAMH2 that is located right next to IAMH1on chromosomeⅣin Arabidopsis.We generated iamh1 iamh2 double mutants using our CRISPR/Cas9gene editing technology.We showed that disruption of the IAMH genes rendered Arabidopsis plants resistant to IAM treatments and also suppressed the iaaM overexpression phenotypes,suggesting that IAMH1 and IAMH2 are the main enzymes responsible for converting IAM into indole-3-acetic acid(IAA)in Arabidopsis.The iamh double mutants did not display obvious developmental defects,indicating that IAM does not play a major role in auxin biosynthesis under normal growth conditions.Our findings provide a solid foundation for clarifying the roles of IAM in auxin biosynthesis and plant development.展开更多
Barley(Hordeum vulgare ssp.vulgare)is one of the first crops to be domesticated and is adapted to a wide range of environments.Worldwide barley germplasm collections possess valuable allelic variations that could furt...Barley(Hordeum vulgare ssp.vulgare)is one of the first crops to be domesticated and is adapted to a wide range of environments.Worldwide barley germplasm collections possess valuable allelic variations that could further improve barley productivity.Although barley genomics has offered a global picture of allelic variation among varieties and its association with various agronomic traits,polymorphisms from East Asian varieties remain scarce.In this study,we analyze exome polymorphisms in a panel of 274 barley varieties collected worldwide,including 137 varieties from East Asian countries and Ethiopia.We reveal the underlying population structure and conduct genome-wide association studies for 10 agronomic traits.Moreover,we examin genome-wide associations for traits related to grain size such as awn length and glume length.Our results demonstrate the value of diverse barley germplasm panels containing Eastern varieties,highlighting their distinct genomic signatures relative to Western subpopulations.展开更多
Plants as sessile organisms are continuously exposed to abiotic stress conditions that impose numerous detrimental effects and cause tremendous loss of yield. Abiotic stresses, including high sunlight, confer serious ...Plants as sessile organisms are continuously exposed to abiotic stress conditions that impose numerous detrimental effects and cause tremendous loss of yield. Abiotic stresses, including high sunlight, confer serious damage on the photosynthetic machinery of plants. Photosystem II (PSII) is one of the most susceptible components of the photosynthetic machinery that bears the brunt of abiotic stress. In addition to the generation of reactive oxygen species (ROS) by abiotic stress, ROS can also result from the absorption of excessive sunlight by the light-harvesting complex. ROS can damage the photosynthetic apparatus, particularly PSII, resulting in photoinhibition due to an imbalance in the photosynthetic redox signaling pathways and the inhibition of PSII repair. Designing plants with improved abiotic stress tolerance will require a comprehensive understanding of ROS signaling and the regulatory functions of various components, including protein kinases, transcription factors, and phytohormones, in the responses of photosynthetic machinery to abiotic stress. Bioenergetics approaches, such as chlorophyll a transient kinetics analysis, have facilitated our understanding of plant vitality and the assessment of PSII efficiency under adverse environmental conditions. This review discusses the current understanding and indicates potential areas of further studies on the regulation of the photosynthetic machinery under abiotic stress.展开更多
Potassium (K+) is an essential macronutrient in plants and a lack of K+ significantly reduces the potential for plant growth and development. By contrast, sodium (Na+), while beneficial to some extent, at high ...Potassium (K+) is an essential macronutrient in plants and a lack of K+ significantly reduces the potential for plant growth and development. By contrast, sodium (Na+), while beneficial to some extent, at high concentrations it disturbs and inhibits various physiological processes and plant growth. Due to their chemical similarities, some functions of K+ can be undertaken by Na+ but K+ homeostasis is severely affected by salt stress, on the other hand. Recent advances have highlighted the fascinating regulatory mechanisms of K+ and Na+ transport and signaling in plants. This review summarizes three major topics: (i) the transport mechanisms of K+ and Na+ from the soil to the shoot and to the cellular - compartments; (ii) the mechanisms through which plants sense and respond to K+ and Na+ availability; and (iii) the components involved in maintenance of K+/Na+ homeostasis in plants under salt stress.展开更多
Root-knot nematodes(RKNs;genus Meloidogyne)are a class of plant parasites that infect the roots of many plant species.It is believed that RKNs target certain signaling molecules derived from plants to locate their hos...Root-knot nematodes(RKNs;genus Meloidogyne)are a class of plant parasites that infect the roots of many plant species.It is believed that RKNs target certain signaling molecules derived from plants to locate their hosts;however,currently,no plant compound has been unambiguously identified as a universal RKN attractant.To address this question,we screened a chemical library of synthetic compounds for Meloidogyne incognita attractants.The breakdown product of aminopropylam ino-anthraquinone,1,3-diam inopropane,as well as its related compounds,putrescine and cadaverine,were found to attract M.incognita.After exam ining various polyamines,M.incognita were found to be attracted specifically by natural com pounds that possess three to five methylene groups between two terminal amino groups.Using cryo-TO F-SIM S/SEM,cadaverine was indeed detected in soybean root cortex cells and the surrounding rhizosphere,establishing a chemical gradient.In addition to cadaverine,putrescine and 1,3-diam inopropane were also detected in root exudate by HPLC-MS/MS.Furtherm ore,exogenously applied cadaverine is sufficient to enhance M.incognita infection of Arabidopsis seedlings.These results suggest that M.incognita is likely attracted by polyam ines to locate the appropriate host plants,and the naturally occurring polyamines have potential applications in agriculture in developing protection strategies for crops from RKN infection.展开更多
Summary of main observation and conclusion A rigid C2-symmetric chiral bipyridine ligand Z-bpy with a triptycene-like backbone was designed and synthesized from simple chemicals in a scalable route.Using this new liga...Summary of main observation and conclusion A rigid C2-symmetric chiral bipyridine ligand Z-bpy with a triptycene-like backbone was designed and synthesized from simple chemicals in a scalable route.Using this new ligand,copper(Ⅰ) catalyzed cyclopropanation of styrenes with commercial ethyl diazoacetate produced various corresponding cyclopropanes in high yields,diastereoselectivity and enantioselectivity up to 97% ee.展开更多
Strigolactones,a class of plant hormones with multiple functions,mediate plant-plant and plantmicroorganism communications in the rhizosphere.In this study,we developed potent strigolactone antagonists,which covalentl...Strigolactones,a class of plant hormones with multiple functions,mediate plant-plant and plantmicroorganism communications in the rhizosphere.In this study,we developed potent strigolactone antagonists,which covalently bindto the strigolactone receptor D14,by preparing an array of triazole urea compounds.Using yeast two-hybrid and rice-tillering assays,we identified a triazole urea compound KK094 as a potent inhibitor of strigolactone receptors.Liquid chromatography-tandem mass spectrometry analysis and X-ray crystallography revealed that KK094 was hydrolyzed by D14,and that a reaction product of this degradation covalently binds to the Ser residue of the catalytic triad of D14.Furthermore,we identified two triazole urea compounds KK052 and KK073,whose effects on D14-D53/D14-SLR1 complex formation were opposite due to the absence (KK052)or presence (KK073)of a trifluoromethyl group on their phenyl ring.These results demonstrate that triazole urea compounds are potentially powerful tools for agricultural application and may be useful for the elucidation of the complicated mechanism underlying strigolactone perception.展开更多
Vacuoles are suggested to play crucial roles in plant defense-related cell death. During programmed cell death, previous live cell imaging studies have observed vacuoles to become simpler in structure and have implica...Vacuoles are suggested to play crucial roles in plant defense-related cell death. During programmed cell death, previous live cell imaging studies have observed vacuoles to become simpler in structure and have implicated this simplification as a prelude to the vacuole's rupture and consequent lysis of the plasma membrane. Here, we examined dynamics of the vacuole in cell cycle-synchronized tobacco BY-2 (Nicotiana tabacum L. cv. Bright Yellow 2) cells during ceil death induced by application of culture filtrates of Erwinia carotovora. The filtrate induced death in about 90% of the cells by 24 h. Prior to cell death, vacuole shape simplified and endoplasmic actin filaments disassembled; however, the vacuoles did not rupture until after plasma membrane integrity was lost. Instead of facilitating rupture, the simplification of vacuole structure might play a role in the retrieval of membrane components needed for defense-related cell death.展开更多
The polymerization of C5 fraction without separation and concentration by using a commercial available Nd(P204)3/ AliBu3/AlEt2Cl has afforded for the first time a new kind of 1,3-pentadiene-isoprene random copolymers ...The polymerization of C5 fraction without separation and concentration by using a commercial available Nd(P204)3/ AliBu3/AlEt2Cl has afforded for the first time a new kind of 1,3-pentadiene-isoprene random copolymers as rubber materials. Isoprene (IP) and E-1,3-pentadiene (EPD) acted as polymerization monomers, cyclopentadiene acted as poison, and other substances like alkanes, monoolefins, Z-1,3-pentadiene acted as solvents in this multicomponent C5 fraction polymerization system. The data of kinetic experiments, NMR, and DSC indicated that the polymerization of C5 fraction by Nd(P204)3/AliBu3/AlEt2Cl afforded the IP-EPD random copolymers. By controlling polymerization conditions such as [Al]/[Nd]/[Cl] molar ratio and polymerization temperature, the random EPD-IP copolymers containing high cis-1,4-poly(IP)(with selectivity 96%) and moderate cis-1,4-poly(EPD)(with selectivity 60%) units with a low glass transition temperature (about 60 ℃), controllable molecular weight (Mn = 3.8 × 10^4-14.3 × 104), and moderate molecular weight distribution (Mw/Mn = 2.17-2.78) were obtained in a high yield.展开更多
The dynamic behavior of organelles is essential for plant survival under various environmental conditions. Plant organelles, with various functions,migrate along actin filaments and contact other types of organelles, ...The dynamic behavior of organelles is essential for plant survival under various environmental conditions. Plant organelles, with various functions,migrate along actin filaments and contact other types of organelles, leading to physical interactions at a specific site called the membrane contact site. Recent studies have revealed the importance of physical interactions in maintaining efficient metabolite flow between organelles.In this review, we first summarize peroxisome function under different environmental conditions and growth stages to understand organelle interactions. We then discuss current knowledge regarding the interactions between peroxisome and other organelles, i.e., the oil bodies, chloroplast, and mitochondria from the perspective of metabolic and physiological regulation, with reference to various organelle interactions and techniques for estimating organelle interactions occurring in plant cells.展开更多
The global population is expected to increase by 10 billion by 2050,the demand for food and water is also likely to increase.Several factors intensify the growing water scarcity,such as inefficient water use in the fo...The global population is expected to increase by 10 billion by 2050,the demand for food and water is also likely to increase.Several factors intensify the growing water scarcity,such as inefficient water use in the food value chain and inadequate infrastructure to save water.The changing climate also exacerbates the rising temperature by making the drier areas drier and negatively impacting agriculture production in most parts of the world.A decrease in precipitation has been observed in the tropics and sub-tropics,such as the Sahel region of Southern Africa,the Mediterranean,South Asia,and the Southwest of US since 1970(https://www.climatecommunication.org).展开更多
Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors controlling the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ...Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors controlling the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ACTIVITY (ICA), a gene encoding a putative pectin methyltransferase, which could function as a modulator for the meristematic activity of fascicular and interfascicular cambium in Arabidopsis. An overexpressing transgenic line, 35S:'1CA, showed accelerated stern elongation and radial thickening, resulting in increased accumulation of biomass, and increased levels of cytokinins (CKs) and gibberellins (GAs). Expression of genes encoding pectin methylesterases involved in pectin modification together with pectin methyltransferases was highly induced in 355::ICA, which might contribute to an increase of methanol emission as a byproduct in 35S:ICA. Methanol treatment induced the expression of GA- or CK-responsive genes and stimulated plant growth. Overall, we propose that ectopic expression of ICA increases cambial activity by regulating CK and GA homeostasis, and methanol emission, eventually leading to stem elongation and radial growth in the inflorescence stem.展开更多
The cyclocopolymerization of 1,6-heptadiene (HPD) with ethylene (E) by a series of half-sandwich scandium alkyl catalysts bearing various auxiliary ligands have been examined. Significant ligand influence on the c...The cyclocopolymerization of 1,6-heptadiene (HPD) with ethylene (E) by a series of half-sandwich scandium alkyl catalysts bearing various auxiliary ligands have been examined. Significant ligand influence on the copolymerization activity and selectivity was observed. In combination with one equivalent of [Ph3C][B(C6F5)4], the half-sandwich scandium dialkyl complexes bearing a Lewis base THF (1) or an NHC side arm (2) yielded the copolymer products together with cross-linked polymers in the copolymerization of HPD with ethylene. In contrast, the THF-free complexes Cp'Sc(CH2C6H4NMe2-o)2 (3: Cp' = C5H5; 4: Cp' = CsMe4SiMe3) and the phosphine oxide side-arm containing complex (C5Me4SiMe2CH2(O)PPh2)Sc(CH2SiM%)2 (5) showed excellent activity and selectivity for the cyclocopolymerization reaction, without giving cross-linked products. The 1H and 13C NMR analyses revealed that the resulting copolymers consist of E-E sequences and six-membered ring methylene-1,3-cyclohexane (MCH) and five-membered ring ethylene-1,2-cyclopentane (ECP) units. The HPD content in the co- polymer products could be easily controlled by changing the feeding amount of HPD under 1 atm of ethylene.展开更多
基金supported by AMED Grants(Nos.JP16cm0106112 and JP16cm0106002)JSPS KAKENHI Grants(Nos.JP17H06412,18H05503,JP19K05744,JP20K05857,JP20H05620,JP21H04720,JP22H04922,and JP22K05363).
文摘Dihydroorotate dehydrogenase(DHODH)is a central enzyme of the de novo pyrimidine biosynthesis pathway and is a promising drug target for the treatment of cancer and autoimmune diseases.This study presents the identification of a potent DHODH inhibitor by proteomic profiling.Cell-based screening revealed that NPD723,which is reduced to H-006 in cells,strongly induces myeloid differentiation and inhibits cell growth in HL-60 cells.H-006 also suppressed the growth of various cancer cells.Proteomic profiling of NPD723-treated cells in ChemProteoBase showed that NPD723 was clustered with DHODH inhibitors.H-006 potently inhibited human DHODH activity in vitro,whereas NPD723 was approximately 400 times less active than H-006.H-006-induced cell death was rescued by the addition of the DHODH product orotic acid.Moreover,metabolome analysis revealed that H-006 treatment promotes marked accumulation of the DHODH substrate dihydroorotic acid.These results suggest that NPD723 is reduced in cells to its active metabolite H-006,which then targets DHODH and suppresses cancer cell growth.Thus,H-006-related drugs represent a potentially powerful treatment for cancer and other diseases.
基金The present work was supported by JSPS KAKENHI(Grant number 18H05159)in Scientific Research on Innovative Areas“Innovations for Light Energy Conversion(I4 LEC)”from MEXT,Japan,and was also supported by the JST Strategic International Collaborative Research Program(SICORP),Japan(Grant number JPMJSC18H7)International Science and Technology Cooperation Program(Grant No.2017YFE0127800),China.
文摘Seeking and developing efficient CO_(2)reduction reaction(CO_(2)RR)electrocatalysts is a hot topic in this era of global warming.Among material candidates for sustainable and cost-effective applications,metal sulfides have attracted attention as promising nature-inspired materials due to multiple adsorption sites which are enhanced by the covalent character of sulfur.This article summarizes the current status regarding the utilization and development of metal sulfide materials as CO_(2)RR electrocatalysts.First,the research background and basic principles of electrochemical CO_(2)RR are introduced.Next,an overview of the main obstacles to developing efficient CO_(2)RR electrocatalysts is presented.The section is followed by a summary of the empirical evidence supporting the application of metal sulfides as CO_(2)RR electrocatalysts beside nature-inspired motivation.The summary of synthesis methods of various metal sulfides is also presented.Furthermore,the paper also highlights the recent works on metal sulfide as efficient CO_(2)RR including the undertaking strategy on the activity enhancement,and finally,discusses the challenges and prospect of metal sulfides-based CO_(2)RR electrocatalysts.Despite recent efforts,metal sulfides remain relatively unexplored as materials for CO_(2)RR electrocatalytic applications.Therefore,this review aims to stimulate novel ideas and research for improved catalyst designs and functionality.
文摘Molybdenum sulfides are promising electrocatalysts for the hydrogen evolution reaction(HER).Sand Mo‐related species have been proposed as the active site for forming adsorbed hydrogen to initiate the HER;however,the nature of the interaction between Mo centers and S ligands is unclear.Further,the development of cost‐effective water‐splitting systems using neutral water as a proton source for H2evolution is highly desirable,whereas the mechanism of the HER at neutral pH is rarely discussed.Here,the structural change in the Mo?Mo and S?S species in a synthesized molybdenum sulfide was monitored at neutral pH using in situ electrochemical Raman spectroscopy.Analysis of the potential dependent Raman spectra revealed that the band assigned to a terminal S?S species emerged along with synchronized changes in the frequency of the Mo?Mo,Mo3?μ3S,and Mo?S vibrational bands.This indicates that Mo?Mo bonds and terminal S?S ligands play synergistic roles in facilitating hydrogen evolution,likely via the internal reorganization of trinuclear Mo3?thio species.The nature and role of metal‐ligand interactions in the HER revealed in this study demonstrated a mechanism that is distinct from those reported previously in which the S or Mo sites function independently.
基金supported by the National Research Foundation of South Korea(Grant Nos.NRF-2020R1A2C1007778 and 2015K2A2A4000129)。
文摘Abiotic stress confers serious damage to the photosynthetic machinery,often resulting in plant growth inhibition.Hypothetical chloroplast open reading frame 3(Ycf3)-interacting protein 1(Y3IP1)is a nucleus-encoded thylakoid protein and plays an essential role in the assembly of photosystem I.The full-length cDNA over-expresser(FOX)gene-hunting system is an approach using systemically generated gain-of-function mutants.Among the FOX-rice lines,a line CE175 overexpressing rice Y3IP1gene(Os Y3IP1)displayed less inhibition of root growth under saline(NaCl)stress.The expression of Os Y3IP1 was up-regulated under saline and alkaline(Na2CO3)stresses in the rice variety Kitaake.After saline and alkaline treatments,transgenic Kitaake overexpressing OsY3IP1-GFP(OsY3IP1-GFPox/Kit)displayed higher levels of chlorophyll content compared to Kitaake.Under the stress conditions,the maximum quantum yield of photosystem II photochemistry levels was higher in OsY3IP1-GFPox/Kit than in Kitaake.The increased tolerance conferred by OsY3IP1 overexpression correlated with reduced reactive oxygen species accumulation.Our data provide new insights into the possible role of OsY3IP1 in the pathway suppressing photooxidative damage under stress conditions.These features can be further exploited to improve saline and alkaline tolerances of rice plants in future.
文摘Population genetics studies of allopolyploid species lag behind those of diploid species because of practical difficulties in analysis of homeologs-duplicated gene copies originating from hybridized parental species. Pool-Seq, i.e. massive parallel sequencing of pooled individuals, has high potential for detecting nucleotide polymorphisms within and among multiple populations;however, its use has been limited to diploid species. We applied Pool-Seq to an allopolyploid species by developing a bioinformatic pipeline that assigns reads to each homeolog as well as to each polymorphic allele within each homeolog. We simultaneously sequenced eight genes from twenty individuals from each of 24 populations, and found over 100 polymorphic sites in each homeolog. For two sites, we estimated allele frequencies using the number of reads and then validated these estimations by making individual-based estimations. Pool-Seq using our bioinformatic pipeline allows efficient evaluation of nucleotide polymorphisms in a large number of individuals, even in allopolyploid species.
文摘Indole-3-acetamide(IAM)is the first confirmed auxin biosynthetic intermediate in some plant pathogenic bacteria.Exogenously applied IAM or production of IAM by overexpressing the bacterial iaaM gene in Arabidopsis causes auxin overproduction phenotypes.However,it is still inconclusive whether plants use IAM as a key precursor for auxin biosynthesis.Herein,we reported the isolation IAM HYDROLASE 1(IAMH1)gene in Arabidopsis from a forward genetic screen for IAM-insensitive mutants that display normal auxin sensitivities.IAMH1 has a close homolog named IAMH2 that is located right next to IAMH1on chromosomeⅣin Arabidopsis.We generated iamh1 iamh2 double mutants using our CRISPR/Cas9gene editing technology.We showed that disruption of the IAMH genes rendered Arabidopsis plants resistant to IAM treatments and also suppressed the iaaM overexpression phenotypes,suggesting that IAMH1 and IAMH2 are the main enzymes responsible for converting IAM into indole-3-acetic acid(IAA)in Arabidopsis.The iamh double mutants did not display obvious developmental defects,indicating that IAM does not play a major role in auxin biosynthesis under normal growth conditions.Our findings provide a solid foundation for clarifying the roles of IAM in auxin biosynthesis and plant development.
基金supported by a Grant-in-Aid for Scientific Research(B)(grant no.15KT0038 to K.M.)a Grant-in-Aid for Scientific Research(C)(grant no.19K11861 to K.M.and R.N.)of the Japan Society for the Promotion of Scienceby CREST(grant no.JPMJCR16O4 to K.M.)of the Japan Science and Technology Agency。
文摘Barley(Hordeum vulgare ssp.vulgare)is one of the first crops to be domesticated and is adapted to a wide range of environments.Worldwide barley germplasm collections possess valuable allelic variations that could further improve barley productivity.Although barley genomics has offered a global picture of allelic variation among varieties and its association with various agronomic traits,polymorphisms from East Asian varieties remain scarce.In this study,we analyze exome polymorphisms in a panel of 274 barley varieties collected worldwide,including 137 varieties from East Asian countries and Ethiopia.We reveal the underlying population structure and conduct genome-wide association studies for 10 agronomic traits.Moreover,we examin genome-wide associations for traits related to grain size such as awn length and glume length.Our results demonstrate the value of diverse barley germplasm panels containing Eastern varieties,highlighting their distinct genomic signatures relative to Western subpopulations.
文摘Plants as sessile organisms are continuously exposed to abiotic stress conditions that impose numerous detrimental effects and cause tremendous loss of yield. Abiotic stresses, including high sunlight, confer serious damage on the photosynthetic machinery of plants. Photosystem II (PSII) is one of the most susceptible components of the photosynthetic machinery that bears the brunt of abiotic stress. In addition to the generation of reactive oxygen species (ROS) by abiotic stress, ROS can also result from the absorption of excessive sunlight by the light-harvesting complex. ROS can damage the photosynthetic apparatus, particularly PSII, resulting in photoinhibition due to an imbalance in the photosynthetic redox signaling pathways and the inhibition of PSII repair. Designing plants with improved abiotic stress tolerance will require a comprehensive understanding of ROS signaling and the regulatory functions of various components, including protein kinases, transcription factors, and phytohormones, in the responses of photosynthetic machinery to abiotic stress. Bioenergetics approaches, such as chlorophyll a transient kinetics analysis, have facilitated our understanding of plant vitality and the assessment of PSII efficiency under adverse environmental conditions. This review discusses the current understanding and indicates potential areas of further studies on the regulation of the photosynthetic machinery under abiotic stress.
文摘Potassium (K+) is an essential macronutrient in plants and a lack of K+ significantly reduces the potential for plant growth and development. By contrast, sodium (Na+), while beneficial to some extent, at high concentrations it disturbs and inhibits various physiological processes and plant growth. Due to their chemical similarities, some functions of K+ can be undertaken by Na+ but K+ homeostasis is severely affected by salt stress, on the other hand. Recent advances have highlighted the fascinating regulatory mechanisms of K+ and Na+ transport and signaling in plants. This review summarizes three major topics: (i) the transport mechanisms of K+ and Na+ from the soil to the shoot and to the cellular - compartments; (ii) the mechanisms through which plants sense and respond to K+ and Na+ availability; and (iii) the components involved in maintenance of K+/Na+ homeostasis in plants under salt stress.
基金This work was supported by JSPS KAKENHI grants(25252032 and 15H01230 to K.F.,16H04168 to K.T.,24114009,24370024,16K14757,17H03967,and 18H05487 to S.S.)L.P.-B.and B.F.are supported by INRA and the French Government(National Research Agency,ANR)through the"Investments for the Future"LABEX SIGNALIFE program,reference no.ANR-11-LABX-0028-01.
文摘Root-knot nematodes(RKNs;genus Meloidogyne)are a class of plant parasites that infect the roots of many plant species.It is believed that RKNs target certain signaling molecules derived from plants to locate their hosts;however,currently,no plant compound has been unambiguously identified as a universal RKN attractant.To address this question,we screened a chemical library of synthetic compounds for Meloidogyne incognita attractants.The breakdown product of aminopropylam ino-anthraquinone,1,3-diam inopropane,as well as its related compounds,putrescine and cadaverine,were found to attract M.incognita.After exam ining various polyamines,M.incognita were found to be attracted specifically by natural com pounds that possess three to five methylene groups between two terminal amino groups.Using cryo-TO F-SIM S/SEM,cadaverine was indeed detected in soybean root cortex cells and the surrounding rhizosphere,establishing a chemical gradient.In addition to cadaverine,putrescine and 1,3-diam inopropane were also detected in root exudate by HPLC-MS/MS.Furtherm ore,exogenously applied cadaverine is sufficient to enhance M.incognita infection of Arabidopsis seedlings.These results suggest that M.incognita is likely attracted by polyam ines to locate the appropriate host plants,and the naturally occurring polyamines have potential applications in agriculture in developing protection strategies for crops from RKN infection.
基金provided by the National Natural Science Foundation of China (Nos.21672168 and 21702157)China Postdoctoral Science Foundation (No.2017M623148)+1 种基金the National Postdoctoral Program for Innovative Talents (No.BX201600122)Key Laboratory Construction Program of Xi'an Municipal Bureau of Science and Technology (No.201805056ZD7CG40).
文摘Summary of main observation and conclusion A rigid C2-symmetric chiral bipyridine ligand Z-bpy with a triptycene-like backbone was designed and synthesized from simple chemicals in a scalable route.Using this new ligand,copper(Ⅰ) catalyzed cyclopropanation of styrenes with commercial ethyl diazoacetate produced various corresponding cyclopropanes in high yields,diastereoselectivity and enantioselectivity up to 97% ee.
文摘Strigolactones,a class of plant hormones with multiple functions,mediate plant-plant and plantmicroorganism communications in the rhizosphere.In this study,we developed potent strigolactone antagonists,which covalently bindto the strigolactone receptor D14,by preparing an array of triazole urea compounds.Using yeast two-hybrid and rice-tillering assays,we identified a triazole urea compound KK094 as a potent inhibitor of strigolactone receptors.Liquid chromatography-tandem mass spectrometry analysis and X-ray crystallography revealed that KK094 was hydrolyzed by D14,and that a reaction product of this degradation covalently binds to the Ser residue of the catalytic triad of D14.Furthermore,we identified two triazole urea compounds KK052 and KK073,whose effects on D14-D53/D14-SLR1 complex formation were opposite due to the absence (KK052)or presence (KK073)of a trifluoromethyl group on their phenyl ring.These results demonstrate that triazole urea compounds are potentially powerful tools for agricultural application and may be useful for the elucidation of the complicated mechanism underlying strigolactone perception.
基金supported by JSPS KAKENHI Grant Numbers 25711017 (T.H.), 25291056 (S.H.) and 24114007 (S.H.)
文摘Vacuoles are suggested to play crucial roles in plant defense-related cell death. During programmed cell death, previous live cell imaging studies have observed vacuoles to become simpler in structure and have implicated this simplification as a prelude to the vacuole's rupture and consequent lysis of the plasma membrane. Here, we examined dynamics of the vacuole in cell cycle-synchronized tobacco BY-2 (Nicotiana tabacum L. cv. Bright Yellow 2) cells during ceil death induced by application of culture filtrates of Erwinia carotovora. The filtrate induced death in about 90% of the cells by 24 h. Prior to cell death, vacuole shape simplified and endoplasmic actin filaments disassembled; however, the vacuoles did not rupture until after plasma membrane integrity was lost. Instead of facilitating rupture, the simplification of vacuole structure might play a role in the retrieval of membrane components needed for defense-related cell death.
基金financially supported by the National Natural Science Foundation of China (No. 21674016)
文摘The polymerization of C5 fraction without separation and concentration by using a commercial available Nd(P204)3/ AliBu3/AlEt2Cl has afforded for the first time a new kind of 1,3-pentadiene-isoprene random copolymers as rubber materials. Isoprene (IP) and E-1,3-pentadiene (EPD) acted as polymerization monomers, cyclopentadiene acted as poison, and other substances like alkanes, monoolefins, Z-1,3-pentadiene acted as solvents in this multicomponent C5 fraction polymerization system. The data of kinetic experiments, NMR, and DSC indicated that the polymerization of C5 fraction by Nd(P204)3/AliBu3/AlEt2Cl afforded the IP-EPD random copolymers. By controlling polymerization conditions such as [Al]/[Nd]/[Cl] molar ratio and polymerization temperature, the random EPD-IP copolymers containing high cis-1,4-poly(IP)(with selectivity 96%) and moderate cis-1,4-poly(EPD)(with selectivity 60%) units with a low glass transition temperature (about 60 ℃), controllable molecular weight (Mn = 3.8 × 10^4-14.3 × 104), and moderate molecular weight distribution (Mw/Mn = 2.17-2.78) were obtained in a high yield.
基金supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT, KAKENHI Grant-in-Aid for Scientific Research on Innovative Areas to M.N.[No.22120007])a fund to M.N. from Wyeth Foundation
文摘The dynamic behavior of organelles is essential for plant survival under various environmental conditions. Plant organelles, with various functions,migrate along actin filaments and contact other types of organelles, leading to physical interactions at a specific site called the membrane contact site. Recent studies have revealed the importance of physical interactions in maintaining efficient metabolite flow between organelles.In this review, we first summarize peroxisome function under different environmental conditions and growth stages to understand organelle interactions. We then discuss current knowledge regarding the interactions between peroxisome and other organelles, i.e., the oil bodies, chloroplast, and mitochondria from the perspective of metabolic and physiological regulation, with reference to various organelle interactions and techniques for estimating organelle interactions occurring in plant cells.
文摘The global population is expected to increase by 10 billion by 2050,the demand for food and water is also likely to increase.Several factors intensify the growing water scarcity,such as inefficient water use in the food value chain and inadequate infrastructure to save water.The changing climate also exacerbates the rising temperature by making the drier areas drier and negatively impacting agriculture production in most parts of the world.A decrease in precipitation has been observed in the tropics and sub-tropics,such as the Sahel region of Southern Africa,the Mediterranean,South Asia,and the Southwest of US since 1970(https://www.climatecommunication.org).
基金the support of “Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ010953022016)” Rural Development Administration, Korea
文摘Cambial activity is a prerequisite for secondary growth in plants; however, regulatory factors controlling the activity of the secondary meristem in radial growth remain elusive. Here, we identified INCREASED CAMBIAL ACTIVITY (ICA), a gene encoding a putative pectin methyltransferase, which could function as a modulator for the meristematic activity of fascicular and interfascicular cambium in Arabidopsis. An overexpressing transgenic line, 35S:'1CA, showed accelerated stern elongation and radial thickening, resulting in increased accumulation of biomass, and increased levels of cytokinins (CKs) and gibberellins (GAs). Expression of genes encoding pectin methylesterases involved in pectin modification together with pectin methyltransferases was highly induced in 355::ICA, which might contribute to an increase of methanol emission as a byproduct in 35S:ICA. Methanol treatment induced the expression of GA- or CK-responsive genes and stimulated plant growth. Overall, we propose that ectopic expression of ICA increases cambial activity by regulating CK and GA homeostasis, and methanol emission, eventually leading to stem elongation and radial growth in the inflorescence stem.
基金supported by Grant-in-aid for Scientific Research (B) (24350030 to M.N.)a Grant-in-Aid for Scientific Research (S) ( 21225004 to Z.H.) from JSPS+1 种基金the National Natural Science Foundation of China (21204008)the Fundamental Research Funds for the Central Universities (DUT12RC(3)94)
文摘The cyclocopolymerization of 1,6-heptadiene (HPD) with ethylene (E) by a series of half-sandwich scandium alkyl catalysts bearing various auxiliary ligands have been examined. Significant ligand influence on the copolymerization activity and selectivity was observed. In combination with one equivalent of [Ph3C][B(C6F5)4], the half-sandwich scandium dialkyl complexes bearing a Lewis base THF (1) or an NHC side arm (2) yielded the copolymer products together with cross-linked polymers in the copolymerization of HPD with ethylene. In contrast, the THF-free complexes Cp'Sc(CH2C6H4NMe2-o)2 (3: Cp' = C5H5; 4: Cp' = CsMe4SiMe3) and the phosphine oxide side-arm containing complex (C5Me4SiMe2CH2(O)PPh2)Sc(CH2SiM%)2 (5) showed excellent activity and selectivity for the cyclocopolymerization reaction, without giving cross-linked products. The 1H and 13C NMR analyses revealed that the resulting copolymers consist of E-E sequences and six-membered ring methylene-1,3-cyclohexane (MCH) and five-membered ring ethylene-1,2-cyclopentane (ECP) units. The HPD content in the co- polymer products could be easily controlled by changing the feeding amount of HPD under 1 atm of ethylene.