The rapid development of high-throughput sequencing techniques has led biology into the big-data era.Data analyses using various bioinformatics tools rely on programming and command-line environments,which are challen...The rapid development of high-throughput sequencing techniques has led biology into the big-data era.Data analyses using various bioinformatics tools rely on programming and command-line environments,which are challenging and time-consuming for most wet-lab biologists.Here,we present TBtools(a Toolkit for Biologists integrating various biological data-handling tools),a stand-alone software with a userfriendly interface.The toolkit incorporates over 130 functions,which are designed to meet the increasing demand for big-data analyses,ranging from bulk sequence processing to interactive data visualization.A wide variety of graphs can be prepared in TBtools using a new plotting engine("JIGplot")developed to maximize their interactive ability;this engine allows quick point-and-click modification of almost every graphic feature.TBtools is platform-independent software that can be run under all operating systems with Java Runtime Environment 1.6 or newer.It is freely available to non-commercial users at https://github.com/CJ-Chen/TBtools/releases.展开更多
Abscisic acid(ABA)is an important phytohormone regulating plant growth,development,and stress responses.It has an essential role in multiple physiological processes of plants,such as stomatal closure,cuticular wax acc...Abscisic acid(ABA)is an important phytohormone regulating plant growth,development,and stress responses.It has an essential role in multiple physiological processes of plants,such as stomatal closure,cuticular wax accumulation,leaf senescence,bud dormancy,seed germination,osmotic regulation,and growth inhibition among many others.Abscisic acid controls downstream responses to abiotic and biotic environmental changes through both transcriptional and posttranscriptional mechanisms.During the past 20 years,ABA biosynthesis and many of its signaling pathways have been well characterized.Here we review the dynamics of ABA metabolic pools and signaling that affects many of its physiological functions.展开更多
CRISPR/Cas9 （clustered regularly interspaced short palindromic repeats/CRISPR-associated Cas9） has been widely used in genome editing in a variety of organisms, including rice （Cong et al., 2013; Feng et al., 2013）.
The limited availability of phosphate （Pi） in most soils results in the manifestation of Pi starvation responses in plants. To dissect the transcriptional regulation of Pi stress-response mechanisms, we have charact...The limited availability of phosphate （Pi） in most soils results in the manifestation of Pi starvation responses in plants. To dissect the transcriptional regulation of Pi stress-response mechanisms, we have characterized the biological role of MYB62, an R2R3-type MYB transcription factor that is induced in response to Pi deficiency. The induction of MYB62 is a specific response in the leaves during Pi deprivation. The MYB62 protein localizes to the nucleus. The overexpression of MYB62 resulted in altered root architecture, Pi uptake, and acid phosphatase activity, leading to decreased total Pi content in the shoots. The expression of several Pi starvation-induced （PSI） genes was also suppressed in the MYB62 overexpressing plants. Overexpression of MYB62 resulted in a characteristic gibberellic acid （GA）-deficient phenotype that could be partially reversed by exogenous application of GA. In addition, the expression of SOC1 and SUPERMAN, molecular reg- ulators of flowering, was suppressed in the MYB62 overexpressing plants. Interestingly, the expression of these genes was also reduced during Pi deprivation in wild-type plants, suggesting a role for GA biosynthetic and floral regulatory genes in Pi starvation responses. Thus, this study highlights the role of MYB62 in the regulation of phosphate starvation responses via changes in GA metabolism and signaling. Such cross-talk between Pi homeostasis and GA might have broader implications on flowering, root development and adaptive mechanisms during nutrient stress.展开更多
Dear Editor Precise modification of eukaryotic genomes has been accom- plished mainly through homology-directed repair （HDR） of DNA double-strand breaks （DSBs） （Hess et al., 2017）. However, the inherent low effi...Dear Editor Precise modification of eukaryotic genomes has been accom- plished mainly through homology-directed repair （HDR） of DNA double-strand breaks （DSBs） （Hess et al., 2017）. However, the inherent low efficiency of homologous recombination and poor availability of exogenous donor DNA as repair templates strongly impede the use of HDR for precise genome editing in many species （Komor et al., 2017a）. To complement the HDR method and circumvent some of its limitations.展开更多
Dear Editor, The class 2/type Ⅱ clustered regularly interspaced short palindromic repeat （CRISPR）/Cas9 system has been used successfully for simultaneous modification of multiple loci in plants. Two general strateg...Dear Editor, The class 2/type Ⅱ clustered regularly interspaced short palindromic repeat （CRISPR）/Cas9 system has been used successfully for simultaneous modification of multiple loci in plants. Two general strategies have been applied to coexpress multiple single guide RNAs （sgRNAs） to achieve multiplex gene editing in plant cells.展开更多
Stomata, the pores formed by a pair of guard cells, are the main gateways for water transpiration and photosynthetic CO2 exchange, as well as pathogen invasion in land plants. Guard cell movement is regulated by a com...Stomata, the pores formed by a pair of guard cells, are the main gateways for water transpiration and photosynthetic CO2 exchange, as well as pathogen invasion in land plants. Guard cell movement is regulated by a combination of environmental factors, including water status, light, CO2 levels and pathogen attack, as well as endogenous signals, such as abscisic acid and apoplastic reactive oxygen species （ROS）. Under abiotic and biotic stress conditions, extracellular ROS are mainly produced by plasma membrane-localized NADPH oxidases, whereas intracellular ROS are produced in multiple organelles. These ROS form a sophisticated cellular signaling network, with the accumulation of apoplastic ROS an early hallmark of stomatal movement. Here, we review recent progress in understanding the molecular mechanisms of the ROS signaling network, primarily during drought stress and pathogen attack. We summarize the roles of apoplastic ROS in regulating stomatal movement, ABA and CO2 signaling, and immunity responses. Finally, we discuss ROS accumulation and communication between organelles and cells. This information provides a conceptual framework for understanding how ROS signaling is integrated with various signaling pathways during plant responses to abiotic and biotic stress stimuli.展开更多
The seed germination and seedling growth of pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee cv. Hanxiao） were not significantly inhibited until the concentration of NaCl was increased to 150 mm...The seed germination and seedling growth of pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee cv. Hanxiao） were not significantly inhibited until the concentration of NaCl was increased to 150 mmol/L. Treatment of pakchoi seeds with exogenous 5-aminolevulinic acid （ALA）, at concentrations ranging from 0.01 to 10.00 mg/L, promoted seed germination when seeds were stressed by salinity, whereas levulinic acid （LA）, an inhibitor of ALA dehydrase, significantly inhibited seed germination and seedling growth, suggesting that metabolism of ALA into porphyrin compounds was necessary for seed germination and seedling growth. Determination of respiratory rate during seed germination showed that ALA increased seed respiration under both normal conditions and salt stress. Furthermore, salt stress decreased levels of endogenous ALA, as well as heme, in etiolated seedlings. More salt-tolerant cultivars of pakchoi contained higher relative levels of endogenous ALA and heme under conditions of salt stress. These results indicate that salt stress may inhibit the biosynthesis of endogenous ALA and then heme, which is necessary for seed germination, and treatment of seeds with exogenous ALA prior to germination may be associated with the biosynthesis of heme.展开更多
In rice, amylose content （AC） is controlled by a single dominant Waxy gene. We used Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）/CRISPR-associated 9 （Casg） to introduce a loss-of-function m...In rice, amylose content （AC） is controlled by a single dominant Waxy gene. We used Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）/CRISPR-associated 9 （Casg） to introduce a loss-of-function mutation into the Waxy gene in two widely cultivated elite japonica varieties. Our results show that mutations in the Waxy gene reduce AC and convert the rice into glutinous ones without affecting other desirable agronomic traits, offering an effective and easy strategy to improve glutinosity in elite varieties. Importantly, we successfully removed the transgenes from the progeny. Our study provides an example of generating improved crops with potential for commercialization, by editing a gene of interest directly in elite crop varieties.展开更多
Genetic manipulation of genes to upregulate specific branches of metabolic pathways is a method that is commonly used to improve fruit quality.However,the use of a single gene to impact several metabolic pathways is d...Genetic manipulation of genes to upregulate specific branches of metabolic pathways is a method that is commonly used to improve fruit quality.However,the use of a single gene to impact several metabolic pathways is difficult.Here,we show that overexpression of the single gene SlMYB75(SlMYB75-OE)is effective at improving multiple fruit quality traits.In these engineered fruits,the anthocyanin content reached 1.86mg g−1 fresh weight at the red-ripe stage,and these SlMYB75-OE tomatoes displayed a series of physiological changes,including delayed ripening and increased ethylene production.In addition to anthocyanin,the total contents of phenolics,flavonoids and soluble solids in SlMYB75-OE fruits were enhanced by 2.6,4,and 1.2 times,respectively,compared to those of wild-type(WT)fruits.Interestingly,a number of aroma volatiles,such as aldehyde,phenylpropanoid-derived and terpene volatiles,were significantly increased in SlMYB75-OE fruits,with some terpene volatiles showing more than 10 times higher levels than those in WT fruits.Consistent with the metabolic assessment,transcriptomic profiling indicated that the genes involved in the ethylene signaling,phenylpropanoid and isoprenoid pathways were greatly upregulated in SlMYB75-OE fruits.Yeast one-hybrid and transactivation assays revealed that SlMYB75 is able to directly bind to the MYBPLANT and MYBPZM cis-regulatory elements and to activate the promoters of the LOXC,AADC2 and TPS genes.The identification of SlMYB75 as a key regulator of fruit quality attributes through the transcriptional regulation of downstream genes involved in several metabolic pathways opens new avenues towards engineering fruits with a higher sensory and nutritional quality.展开更多
Carotenoids are a diverse group of pigments widely distributed in nature.The vivid yellow,orange,and red colors of many horticultural crops are attributed to the overaccumulation of carotenoids,which contribute to a c...Carotenoids are a diverse group of pigments widely distributed in nature.The vivid yellow,orange,and red colors of many horticultural crops are attributed to the overaccumulation of carotenoids,which contribute to a critical agronomic trait for flowers and an important quality trait for fruits and vegetables.Not only do carotenoids give horticultural crops their visual appeal,they also enhance nutritional value and health benefits for humans.As a result,carotenoid research in horticultural crops has grown exponentially over the last decade.These investigations have advanced our fundamental understanding of carotenoid metabolism and regulation in plants.In this review,we provide an overview of carotenoid biosynthesis,degradation,and accumulation in horticultural crops and highlight recent achievements in our understanding of carotenoid metabolic regulation in vegetables,fruits,and flowers.展开更多
It has been almost 20 years since the first report of a WRKY transcription factor, SPF1, from sweet potato. Great progress has been made since then in establishing the diverse biological roles of WRKY transcription fa...It has been almost 20 years since the first report of a WRKY transcription factor, SPF1, from sweet potato. Great progress has been made since then in establishing the diverse biological roles of WRKY transcription factors in plant growth, development, and responses to biotic and abiotic stress. Despite the functional diversity, almost all ana-lyzed WRKY proteins recognize the TrGACC/T W-box sequences and, therefore, mechanisms other than mere recognition of the core W-box promoter elements are necessary to achieve the regulatory specificity of WRKY transcription factors. Research over the past several years has revealed that WRKY transcription factors physically interact with a wide range of proteins with roles in signaling, transcription, and chromatin remodeling. Studies of WRKY-interacting proteins have provided important insights into the regulation and mode of action of members of the important family of transcrip-tion factors. It has also emerged that the slightly varied WRKY domains and other protein motifs conserved within each of the seven WRKY subfamilies participate in protein-protein interactions and mediate complex functional interactions between WRKY proteins and between WRKY and other regulatory proteins in the modulation of important biologi- cal processes. In this review, we summarize studies of protein-protein interactions for WRKY transcription factors and discuss how the interacting partners contribute, at different levels, to the establishment of the complex regulatory and functional network of WRKY transcription factors.展开更多
Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplas...Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.展开更多
Soil salinity is a major environmental stress that restricts the growth and yield of crops.Understanding the physiological,metabolic,and biochemical responses of plants to salt stress and mining the salt tolerance-ass...Soil salinity is a major environmental stress that restricts the growth and yield of crops.Understanding the physiological,metabolic,and biochemical responses of plants to salt stress and mining the salt tolerance-associated genetic resource in nature will be extremely important for us to cultivate salt-tolerant crops.In this review,we provide a comprehensive summary of the mechanisms of salt stress responses in plants,including salt stress-triggered physiological responses,oxidative stress,salt stress sensing and signaling pathways,organellar stress,ion homeostasis,hormonal and gene expression regulation,metabolic changes,as well as salt tolerance mechanisms in halophytes.Important questions regarding salt tolerance that need to be addressed in the future are discussed.展开更多
The basic leucine zipper(bZIP)transcription factor HY5 plays a multifaceted role in plant growth and development.Here the apple MdHY5 gene was cloned based on its homology with Arabidopsis HY5.Expression analysis demo...The basic leucine zipper(bZIP)transcription factor HY5 plays a multifaceted role in plant growth and development.Here the apple MdHY5 gene was cloned based on its homology with Arabidopsis HY5.Expression analysis demonstrated that MdHY5 transcription was induced by light and abscisic acid treatments.Electrophoretic mobility shift assays and transient expression assays subsequently showed that MdHY5 positively regulated both its own transcription and that of MdMYB10 by binding to E-box and G-box motifs,respectively.Furthermore,we obtained transgenic apple calli that overexpressed the MdHY5 gene,and apple calli coloration assays showed that MdHY5 promoted anthocyanin accumulation by regulating expression of the MdMYB10 gene and downstream anthocyanin biosynthesis genes.In addition,the transcript levels of a series of nitrate reductase genes and nitrate uptake genes in both wild-type and transgenic apple calli were detected.In association with increased nitrate reductase activities and nitrate contents,the results indicated that MdHY5 might be an important regulator in nutrient assimilation.Taken together,these results indicate that MdHY5 plays a vital role in anthocyanin accumulation and nitrate assimilation in apple.展开更多
Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf color.However,the regulatory mechanism of leaf coloration in G.biloba remains unclear.Here,we compared G.biloba gold-colored mutant leaves an...Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf color.However,the regulatory mechanism of leaf coloration in G.biloba remains unclear.Here,we compared G.biloba gold-colored mutant leaves and normal green leaves in cytological,physiological and transcriptomic terms.We found that chloroplasts of the mutant were fewer and smaller,and exhibited ruptured thylakoid membranes,indistinct stromal lamellae and irregularly arranged vesicles.Physiological experiments also showed that the mutant had a lower chlorophyll,lower flavonoid and higher carotenoid contents(especially lutein).We further used transcriptomic sequencing to identify 116 differentially expressed genes(DEGs)and 46 transcription factors(TFs)involved in chloroplast development,chlorophyll metabolism,pigment biosynthesis and photosynthesis.Among these,the chlorophyll biosynthesis-related PPO showed down-regulation,while chlorophyll degradation-related NYC/NOL had up-regulated expression in mutant leaves.Z-ISO,ZDS,and LCYE,which are involved in carotenoid biosynthesis were up-regulated.Quantitative real-time PCR(RT-qPCR)further confirmed the altered expression levels of these genes at three stages.The alteration of PPO and NYC/NOL gene expression might affect chlorophyll biosynthesis and promote degradation of chlorophyll b to chlorophyll a,while the up-regulated genes Z-ISO,ZDS and LCYE enhanced carotenoid accumulation.Consequently,changes in the ratio of carotenoids to chlorophylls were the main factors driving the golden leaf coloration in the mutant G.biloba.展开更多
Flos Lonicerae is a medically useful traditional Chinese medicine herb. However, little is known about the antioxidant properties of Flos Lonicerae extracts. Here the antioxidant capacity of water, methanolic and etha...Flos Lonicerae is a medically useful traditional Chinese medicine herb. However, little is known about the antioxidant properties of Flos Lonicerae extracts. Here the antioxidant capacity of water, methanolic and ethanolic extracts prepared from Flos Lonicerae to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and reduce Fe3+ to Fe2+ is examined. Chlorogenic acid, a major component of Flos Lonicerae, is identified and further purified from 70% ethanolic extract with high performance liquid chromatography (HPLC) and its antioxidant capacity is characterized. The total phenolic compounds and chlorogenic acid con-tents in Flos Lonicerae are determined. The present results demonstrate that the Flos Lonicerae extracts exhibit antioxidant ac-tivity and chlorogenic acid is a major contributor to this activity.展开更多
基金This work was funded by the National Key Research and Developmental Program of China(2018YFD1000104)This work is also supported by awards to R.X.,Y.H.,and H.C.from the National Key Research and Developmental Program of China(2017YFD0101702,2018YFD1000500,2019YFD1000500)+4 种基金the National Science Foundation of China(#31872063)the Special Support Program of Guangdong Province(2019TX05N193)the Key-Area Research and Development Program of Guangdong Province(2018B020202011)the Guangzhou Science and Technology Key Project(201804020063)Support to M.H.F.comes from the NSF Faculty Early Career Development Program(IOS-1942437).
文摘The rapid development of high-throughput sequencing techniques has led biology into the big-data era.Data analyses using various bioinformatics tools rely on programming and command-line environments,which are challenging and time-consuming for most wet-lab biologists.Here,we present TBtools(a Toolkit for Biologists integrating various biological data-handling tools),a stand-alone software with a userfriendly interface.The toolkit incorporates over 130 functions,which are designed to meet the increasing demand for big-data analyses,ranging from bulk sequence processing to interactive data visualization.A wide variety of graphs can be prepared in TBtools using a new plotting engine("JIGplot")developed to maximize their interactive ability;this engine allows quick point-and-click modification of almost every graphic feature.TBtools is platform-independent software that can be run under all operating systems with Java Runtime Environment 1.6 or newer.It is freely available to non-commercial users at https://github.com/CJ-Chen/TBtools/releases.
基金supported by the Shanghai Center for Plant Stress Biology from the Chinese Academy of Sciences, the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB27040107)the National Natural Science Foundation of China (31970293)the Shanghai Pujiang Program (18PJ1410900)
文摘Abscisic acid(ABA)is an important phytohormone regulating plant growth,development,and stress responses.It has an essential role in multiple physiological processes of plants,such as stomatal closure,cuticular wax accumulation,leaf senescence,bud dormancy,seed germination,osmotic regulation,and growth inhibition among many others.Abscisic acid controls downstream responses to abiotic and biotic environmental changes through both transcriptional and posttranscriptional mechanisms.During the past 20 years,ABA biosynthesis and many of its signaling pathways have been well characterized.Here we review the dynamics of ABA metabolic pools and signaling that affects many of its physiological functions.
文摘CRISPR/Cas9 （clustered regularly interspaced short palindromic repeats/CRISPR-associated Cas9） has been widely used in genome editing in a variety of organisms, including rice （Cong et al., 2013; Feng et al., 2013）.
文摘The limited availability of phosphate （Pi） in most soils results in the manifestation of Pi starvation responses in plants. To dissect the transcriptional regulation of Pi stress-response mechanisms, we have characterized the biological role of MYB62, an R2R3-type MYB transcription factor that is induced in response to Pi deficiency. The induction of MYB62 is a specific response in the leaves during Pi deprivation. The MYB62 protein localizes to the nucleus. The overexpression of MYB62 resulted in altered root architecture, Pi uptake, and acid phosphatase activity, leading to decreased total Pi content in the shoots. The expression of several Pi starvation-induced （PSI） genes was also suppressed in the MYB62 overexpressing plants. Overexpression of MYB62 resulted in a characteristic gibberellic acid （GA）-deficient phenotype that could be partially reversed by exogenous application of GA. In addition, the expression of SOC1 and SUPERMAN, molecular reg- ulators of flowering, was suppressed in the MYB62 overexpressing plants. Interestingly, the expression of these genes was also reduced during Pi deprivation in wild-type plants, suggesting a role for GA biosynthetic and floral regulatory genes in Pi starvation responses. Thus, this study highlights the role of MYB62 in the regulation of phosphate starvation responses via changes in GA metabolism and signaling. Such cross-talk between Pi homeostasis and GA might have broader implications on flowering, root development and adaptive mechanisms during nutrient stress.
文摘Dear Editor Precise modification of eukaryotic genomes has been accom- plished mainly through homology-directed repair （HDR） of DNA double-strand breaks （DSBs） （Hess et al., 2017）. However, the inherent low efficiency of homologous recombination and poor availability of exogenous donor DNA as repair templates strongly impede the use of HDR for precise genome editing in many species （Komor et al., 2017a）. To complement the HDR method and circumvent some of its limitations.
文摘Dear Editor, The class 2/type Ⅱ clustered regularly interspaced short palindromic repeat （CRISPR）/Cas9 system has been used successfully for simultaneous modification of multiple loci in plants. Two general strategies have been applied to coexpress multiple single guide RNAs （sgRNAs） to achieve multiplex gene editing in plant cells.
基金supported by the National Key Scientific Research Project(2011CB915400)supported by the National Natural Science Foundation of China(31730007)
文摘Stomata, the pores formed by a pair of guard cells, are the main gateways for water transpiration and photosynthetic CO2 exchange, as well as pathogen invasion in land plants. Guard cell movement is regulated by a combination of environmental factors, including water status, light, CO2 levels and pathogen attack, as well as endogenous signals, such as abscisic acid and apoplastic reactive oxygen species （ROS）. Under abiotic and biotic stress conditions, extracellular ROS are mainly produced by plasma membrane-localized NADPH oxidases, whereas intracellular ROS are produced in multiple organelles. These ROS form a sophisticated cellular signaling network, with the accumulation of apoplastic ROS an early hallmark of stomatal movement. Here, we review recent progress in understanding the molecular mechanisms of the ROS signaling network, primarily during drought stress and pathogen attack. We summarize the roles of apoplastic ROS in regulating stomatal movement, ABA and CO2 signaling, and immunity responses. Finally, we discuss ROS accumulation and communication between organelles and cells. This information provides a conceptual framework for understanding how ROS signaling is integrated with various signaling pathways during plant responses to abiotic and biotic stress stimuli.
基金the Overseas Scholarship Foundation of the Chinese Education Department，国家自然科学基金
文摘The seed germination and seedling growth of pakchoi （Brassica campestris ssp. chinensis var. communis Tsen et Lee cv. Hanxiao） were not significantly inhibited until the concentration of NaCl was increased to 150 mmol/L. Treatment of pakchoi seeds with exogenous 5-aminolevulinic acid （ALA）, at concentrations ranging from 0.01 to 10.00 mg/L, promoted seed germination when seeds were stressed by salinity, whereas levulinic acid （LA）, an inhibitor of ALA dehydrase, significantly inhibited seed germination and seedling growth, suggesting that metabolism of ALA into porphyrin compounds was necessary for seed germination and seedling growth. Determination of respiratory rate during seed germination showed that ALA increased seed respiration under both normal conditions and salt stress. Furthermore, salt stress decreased levels of endogenous ALA, as well as heme, in etiolated seedlings. More salt-tolerant cultivars of pakchoi contained higher relative levels of endogenous ALA and heme under conditions of salt stress. These results indicate that salt stress may inhibit the biosynthesis of endogenous ALA and then heme, which is necessary for seed germination, and treatment of seeds with exogenous ALA prior to germination may be associated with the biosynthesis of heme.
基金supported by the Chinese Academy of SciencesUS NIH Grants R01GM070795 and R01GM059138(to J.K.Z.)the support of the International Postdoctoral Exchange Fellowship Program of China under grant 20140029
文摘In rice, amylose content （AC） is controlled by a single dominant Waxy gene. We used Clustered Regularly Interspaced Short Palindromic Repeats （CRISPR）/CRISPR-associated 9 （Casg） to introduce a loss-of-function mutation into the Waxy gene in two widely cultivated elite japonica varieties. Our results show that mutations in the Waxy gene reduce AC and convert the rice into glutinous ones without affecting other desirable agronomic traits, offering an effective and easy strategy to improve glutinosity in elite varieties. Importantly, we successfully removed the transgenes from the progeny. Our study provides an example of generating improved crops with potential for commercialization, by editing a gene of interest directly in elite crop varieties.
基金supported by the National Key Research and Development Program(2016YFD0400101)the National Natural Science Foundation of China(31572175,31772370)+1 种基金the Fundamental Research Funds for the Central Universities(2018CDXYSM0021)the Committee of Science and Technology of Chongqing(cstckjcxljrc15).
文摘Genetic manipulation of genes to upregulate specific branches of metabolic pathways is a method that is commonly used to improve fruit quality.However,the use of a single gene to impact several metabolic pathways is difficult.Here,we show that overexpression of the single gene SlMYB75(SlMYB75-OE)is effective at improving multiple fruit quality traits.In these engineered fruits,the anthocyanin content reached 1.86mg g−1 fresh weight at the red-ripe stage,and these SlMYB75-OE tomatoes displayed a series of physiological changes,including delayed ripening and increased ethylene production.In addition to anthocyanin,the total contents of phenolics,flavonoids and soluble solids in SlMYB75-OE fruits were enhanced by 2.6,4,and 1.2 times,respectively,compared to those of wild-type(WT)fruits.Interestingly,a number of aroma volatiles,such as aldehyde,phenylpropanoid-derived and terpene volatiles,were significantly increased in SlMYB75-OE fruits,with some terpene volatiles showing more than 10 times higher levels than those in WT fruits.Consistent with the metabolic assessment,transcriptomic profiling indicated that the genes involved in the ethylene signaling,phenylpropanoid and isoprenoid pathways were greatly upregulated in SlMYB75-OE fruits.Yeast one-hybrid and transactivation assays revealed that SlMYB75 is able to directly bind to the MYBPLANT and MYBPZM cis-regulatory elements and to activate the promoters of the LOXC,AADC2 and TPS genes.The identification of SlMYB75 as a key regulator of fruit quality attributes through the transcriptional regulation of downstream genes involved in several metabolic pathways opens new avenues towards engineering fruits with a higher sensory and nutritional quality.
文摘Carotenoids are a diverse group of pigments widely distributed in nature.The vivid yellow,orange,and red colors of many horticultural crops are attributed to the overaccumulation of carotenoids,which contribute to a critical agronomic trait for flowers and an important quality trait for fruits and vegetables.Not only do carotenoids give horticultural crops their visual appeal,they also enhance nutritional value and health benefits for humans.As a result,carotenoid research in horticultural crops has grown exponentially over the last decade.These investigations have advanced our fundamental understanding of carotenoid metabolism and regulation in plants.In this review,we provide an overview of carotenoid biosynthesis,degradation,and accumulation in horticultural crops and highlight recent achievements in our understanding of carotenoid metabolic regulation in vegetables,fruits,and flowers.
文摘It has been almost 20 years since the first report of a WRKY transcription factor, SPF1, from sweet potato. Great progress has been made since then in establishing the diverse biological roles of WRKY transcription factors in plant growth, development, and responses to biotic and abiotic stress. Despite the functional diversity, almost all ana-lyzed WRKY proteins recognize the TrGACC/T W-box sequences and, therefore, mechanisms other than mere recognition of the core W-box promoter elements are necessary to achieve the regulatory specificity of WRKY transcription factors. Research over the past several years has revealed that WRKY transcription factors physically interact with a wide range of proteins with roles in signaling, transcription, and chromatin remodeling. Studies of WRKY-interacting proteins have provided important insights into the regulation and mode of action of members of the important family of transcrip-tion factors. It has also emerged that the slightly varied WRKY domains and other protein motifs conserved within each of the seven WRKY subfamilies participate in protein-protein interactions and mediate complex functional interactions between WRKY proteins and between WRKY and other regulatory proteins in the modulation of important biologi- cal processes. In this review, we summarize studies of protein-protein interactions for WRKY transcription factors and discuss how the interacting partners contribute, at different levels, to the establishment of the complex regulatory and functional network of WRKY transcription factors.
文摘Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.
基金We are grateful to Zichen Xu for assistance in the preparation of the figures.This work was supported by the Strategic Priority Research Program(grant no.XDB27040101)of the Chinese Academy of Sciences.
文摘Soil salinity is a major environmental stress that restricts the growth and yield of crops.Understanding the physiological,metabolic,and biochemical responses of plants to salt stress and mining the salt tolerance-associated genetic resource in nature will be extremely important for us to cultivate salt-tolerant crops.In this review,we provide a comprehensive summary of the mechanisms of salt stress responses in plants,including salt stress-triggered physiological responses,oxidative stress,salt stress sensing and signaling pathways,organellar stress,ion homeostasis,hormonal and gene expression regulation,metabolic changes,as well as salt tolerance mechanisms in halophytes.Important questions regarding salt tolerance that need to be addressed in the future are discussed.
基金This work was supported by grants from the Natural Science Foundation of China(31325024 and 31601742)the Ministry of Education of China(IRT15R42)and Shandong Province Government(SDAIT-06-03).
文摘The basic leucine zipper(bZIP)transcription factor HY5 plays a multifaceted role in plant growth and development.Here the apple MdHY5 gene was cloned based on its homology with Arabidopsis HY5.Expression analysis demonstrated that MdHY5 transcription was induced by light and abscisic acid treatments.Electrophoretic mobility shift assays and transient expression assays subsequently showed that MdHY5 positively regulated both its own transcription and that of MdMYB10 by binding to E-box and G-box motifs,respectively.Furthermore,we obtained transgenic apple calli that overexpressed the MdHY5 gene,and apple calli coloration assays showed that MdHY5 promoted anthocyanin accumulation by regulating expression of the MdMYB10 gene and downstream anthocyanin biosynthesis genes.In addition,the transcript levels of a series of nitrate reductase genes and nitrate uptake genes in both wild-type and transgenic apple calli were detected.In association with increased nitrate reductase activities and nitrate contents,the results indicated that MdHY5 might be an important regulator in nutrient assimilation.Taken together,these results indicate that MdHY5 plays a vital role in anthocyanin accumulation and nitrate assimilation in apple.
基金This work was financially supported by the Natural Science Foundation of China(No.31670181,31670695)the Three New Forestry Engineering Foundation of Jiangsu Province(No.lysx[2016]55).
文摘Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf color.However,the regulatory mechanism of leaf coloration in G.biloba remains unclear.Here,we compared G.biloba gold-colored mutant leaves and normal green leaves in cytological,physiological and transcriptomic terms.We found that chloroplasts of the mutant were fewer and smaller,and exhibited ruptured thylakoid membranes,indistinct stromal lamellae and irregularly arranged vesicles.Physiological experiments also showed that the mutant had a lower chlorophyll,lower flavonoid and higher carotenoid contents(especially lutein).We further used transcriptomic sequencing to identify 116 differentially expressed genes(DEGs)and 46 transcription factors(TFs)involved in chloroplast development,chlorophyll metabolism,pigment biosynthesis and photosynthesis.Among these,the chlorophyll biosynthesis-related PPO showed down-regulation,while chlorophyll degradation-related NYC/NOL had up-regulated expression in mutant leaves.Z-ISO,ZDS,and LCYE,which are involved in carotenoid biosynthesis were up-regulated.Quantitative real-time PCR(RT-qPCR)further confirmed the altered expression levels of these genes at three stages.The alteration of PPO and NYC/NOL gene expression might affect chlorophyll biosynthesis and promote degradation of chlorophyll b to chlorophyll a,while the up-regulated genes Z-ISO,ZDS and LCYE enhanced carotenoid accumulation.Consequently,changes in the ratio of carotenoids to chlorophylls were the main factors driving the golden leaf coloration in the mutant G.biloba.
基金Project (No. 20039902) supported by the Education Committee of Tianjin, China
文摘Flos Lonicerae is a medically useful traditional Chinese medicine herb. However, little is known about the antioxidant properties of Flos Lonicerae extracts. Here the antioxidant capacity of water, methanolic and ethanolic extracts prepared from Flos Lonicerae to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and reduce Fe3+ to Fe2+ is examined. Chlorogenic acid, a major component of Flos Lonicerae, is identified and further purified from 70% ethanolic extract with high performance liquid chromatography (HPLC) and its antioxidant capacity is characterized. The total phenolic compounds and chlorogenic acid con-tents in Flos Lonicerae are determined. The present results demonstrate that the Flos Lonicerae extracts exhibit antioxidant ac-tivity and chlorogenic acid is a major contributor to this activity.
