Jujube(Ziziphus jujuba Mill.),or Chinese date,is the most important species of Rhamnaceae,a large cosmopolitan family,and is one of the oldest cultivated fruit trees in the world.It originates from the middle and lowe...Jujube(Ziziphus jujuba Mill.),or Chinese date,is the most important species of Rhamnaceae,a large cosmopolitan family,and is one of the oldest cultivated fruit trees in the world.It originates from the middle and lower reaches of the Yellow River,the‘mother river’of the Chinese people.It is distributed in at least 48 countries on all continents except Antarctica and is becoming increasingly important,especially in arid and semiarid marginal lands.Based on a systematic analysis of the unique characteristics of jujube,we suggest that it deserves to be recognized as a superfruit.We summarized historical research achievements from the past 3000 years and reviewed recent research advances since 1949 in seven fields,including genome sequencing and application,germplasm resources and systematic taxonomy,breeding and genetics,cultivation theory and techniques,pest control,postharvest physiology and techniques,and nutrition and processing.Based on the challenges facing the jujube industry,we discuss eight research aspects to be focused on in the future.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
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
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
Reporters have been widely used to visualize gene expression,protein localization,and other cellular activities,but the commonly used reporters require special equipment,expensive chemicals,or invasive treatments.Here...Reporters have been widely used to visualize gene expression,protein localization,and other cellular activities,but the commonly used reporters require special equipment,expensive chemicals,or invasive treatments.Here,we construct a new reporter RUBY that converts tyrosine to vividly red betalain,which is clearly visible to naked eyes without the need of using special equipment or chemical treatments.We show that RUBY can be used to noninvasively monitor gene expression in plants.Furthermore,we show that RUBY is an effective selection marker for transformation events in both rice and Arabidopsis.The new reporter will be especially useful for monitoring cellular activities in large crop plants such as a fruit tree under field conditions and for observing transformation and gene expression in tissue culture under sterile conditions.展开更多
Purple-leaf tea plants,as anthocyanin-rich cultivars,are valuable materials for manufacturing teas with unique colors or flavors.In this study,a new purple-leaf cultivar“Zixin”(“ZX”)was examined,and its biochemica...Purple-leaf tea plants,as anthocyanin-rich cultivars,are valuable materials for manufacturing teas with unique colors or flavors.In this study,a new purple-leaf cultivar“Zixin”(“ZX”)was examined,and its biochemical variation and mechanism of leaf color change were elucidated.The metabolomes of leaves of“ZX”at completely purple,intermediately purple,and completely green stages were analyzed using ultra-performance liquid chromatography quadrupole time of flight mass spectrometry(UPLC-QTOF-MS).Metabolites in the flavonoid biosynthetic pathway remained at high levels in purple leaves,whereas intermediates of porphyrin and chlorophyll metabolism and carotenoid biosynthesis exhibited high levels in green leaves.In addition,fatty acid metabolism was more active in purple leaves,and steroids maintained higher levels in green leaves.Saponin,alcohol,organic acid,and terpenoid-related metabolites also changed significantly during the leaf color change process.Furthermore,the substance changes between“ZX”and“Zijuan”(a thoroughly studied purple-leaf cultivar)were also compared.The leaf color change in“Zijuan”was mainly caused by a decrease in flavonoids/anthocyanins.However,a decrease in flavonoids/anthocyanins,an enhancement of porphyrin,chlorophyll metabolism,carotenoid biosynthesis,and steroids,and a decrease in fatty acids synergistically caused the leaf color change in“ZX”.These findings will facilitate comprehensive research on the regulatory mechanisms of leaf color change in purple-leaf tea cultivars.展开更多
Tea is among the world’s most widely consumed non-alcoholic beverages and possesses enormous economic,health,and cultural values.It is produced from the cured leaves of tea plants,which are important evergreen crops ...Tea is among the world’s most widely consumed non-alcoholic beverages and possesses enormous economic,health,and cultural values.It is produced from the cured leaves of tea plants,which are important evergreen crops globally cultivated in over 50 countries.Along with recent innovations and advances in biotechnologies,great progress in tea plant genomics and genetics has been achieved,which has facilitated our understanding of the molecular mechanisms of tea quality and the evolution of the tea plant genome.In this review,we briefly summarize the achievements of the past two decades,which primarily include diverse genome and transcriptome sequencing projects,gene discovery and regulation studies,investigation of the epigenetics and noncoding RNAs,origin and domestication,phylogenetics and germplasm utilization of tea plant as well as newly developed tools/platforms.We also present perspectives and possible challenges for future functional genomic studies that will contribute to the acceleration of breeding programs in tea plants.展开更多
Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,li...Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,limiting the accessibility of the repetitive sequences,the centromeric and telomeric regions,and the study of inheritance of important agronomic traits in these regions.Here,we assembled a telomere-to-telomere(T2T)gap-free reference genome for the cultivar PN40024 using PacBio HiFi long reads.The T2T reference genome(PN_T2T)is 69 Mb longer with 9018 more genes identified than the 12X.v0 version.We annotated 67%repetitive sequences,19 centromeres and 36 telomeres,and incorporated gene annotations of previous versions into the PN_T2T assembly.We detected a total of 377 gene clusters,which showed associations with complex traits,such as aroma and disease resistance.Even though PN40024 derives from nine generations of selfing,we still found nine genomic hotspots of heterozygous sites associated with biological processes,such as the oxidation–reduction process and protein phosphorylation.The fully annotated complete reference genome therefore constitutes an important resource for grapevine genetic studies and breeding programs.展开更多
Fruit cracking is an important problem in horticultural crop production.Polygalacturonase(SlPG)and expansin(SlEXP1)proteins cooperatively disassemble the polysaccharide network of tomato fruit cell walls during ripeni...Fruit cracking is an important problem in horticultural crop production.Polygalacturonase(SlPG)and expansin(SlEXP1)proteins cooperatively disassemble the polysaccharide network of tomato fruit cell walls during ripening and thereby,enable softening.A Golden 2-like(GLK2)transcription factor,SlGLK2 regulates unripe fruit chloroplast development and results in elevated soluble solids and carotenoids in ripe fruit.To determine whether SlPG,SlEXP1,or SlGLK2 influence the rate of tomato fruit cracking,the incidence of fruit epidermal cracking was compared between wild-type,Ailsa Craig(WT)and fruit with suppressed SlPG and SlEXP1 expression(pg/exp)or expressing a truncated nonfunctional Slglk2(glk2).Treating plants with exogenous ABA increases xylemic flow into fruit.Our results showed that ABA treatment of tomato plants greatly increased cracking of fruit from WT and glk2 mutant,but not from pg/exp genotypes.The pg/exp fruit were firmer,had higher total soluble solids,denser cell walls and thicker cuticles than fruit of the other genotypes.Fruit from the ABA treated pg/exp fruit had cell walls with less water-soluble and more ionically and covalently-bound pectins than fruit from the other lines,demonstrating that ripening-related disassembly of the fruit cell wall,but not elimination of SlGLK2,influences cracking.Cracking incidence was significantly correlated with cell wall and wax thickness,and the content of cell wall protopectin and cellulose,but not with Ca^(2+)content.展开更多
Passion fruit(Passiflora edulis Sims)is an economically valuable fruit that is cultivated in tropical and subtropical regions of the world.Here,we report an~1341.7Mb chromosome-scale genome assembly of passion fruit,w...Passion fruit(Passiflora edulis Sims)is an economically valuable fruit that is cultivated in tropical and subtropical regions of the world.Here,we report an~1341.7Mb chromosome-scale genome assembly of passion fruit,with 98.91%(~1327.18Mb)of the assembly assigned to nine pseudochromosomes.The genome includes 23,171 protein-coding genes,and most of the assembled sequences are repetitive sequences,with long-terminal repeats(LTRs)being the most abundant.Phylogenetic analysis revealed that passion fruit diverged after Brassicaceae and before Euphorbiaceae.Ks analysis showed that two whole-genome duplication events occurred in passion fruit at 65 MYA and 12 MYA,which may have contributed to its large genome size.An integrated analysis of genomic,transcriptomic,and metabolomic data showed that‘alpha-linolenic acid metabolism’,‘metabolic pathways’,and‘secondary metabolic pathways’were the main pathways involved in the synthesis of important volatile organic compounds(VOCs)in passion fruit,and this analysis identified some candidate genes,including GDP-fucose Transporter 1-like,Tetratricopeptide repeat protein 33,protein NETWORKED 4B isoform X1,and Golgin Subfamily A member 6-like protein 22.In addition,we identified 13 important gene families in fatty acid pathways and eight important gene families in terpene pathways.Gene family analysis showed that the ACX,ADH,ALDH,and HPL gene families,especially ACX13/14/15/20,ADH13/26/33,ALDH1/4/21,and HPL4/6,were the key genes for ester synthesis,while the TPS gene family,especially PeTPS2/3/4/24,was the key gene family for terpene synthesis.This work provides insights into genome evolution and flavor trait biology and offers valuable resources for the improved cultivation of passion fruit.展开更多
Anthocyanins are biosynthesized on the cytosolic surface of the endoplasmic reticulum and then transported into the vacuole for storage.Glutathione S-transferases(GSTs)are considered to be responsible for the transpor...Anthocyanins are biosynthesized on the cytosolic surface of the endoplasmic reticulum and then transported into the vacuole for storage.Glutathione S-transferases(GSTs)are considered to be responsible for the transport of anthocyanins into the vacuole.However,the regulatory mechanisms of GSTs in plants are still unclear.Here,we performed a genome-wide analysis and identified 69 GST genes in apple.The expression of MdGSTF6 was positively correlated with the anthocyanin content(r=0.949)during‘Yanfu 8’fruit development.The overexpression of MdGSTF6 in the Arabidopsis thaliana tt19 mutant resulted in seedlings of 35S::MdGSTF6-GFP/tt19 that could accumulate anthocyanin and rescue its phenotype,suggesting that MdGSTF6 was an anthocyanin transporter.The silencing of MdGSTF6 affected anthocyanin accumulation in apple fruit.Moreover,the knockdown of MdGSTF6 by RNA interference in cultured‘Gala’seedlings inhibited anthocyanin accumulation.The interaction experiments showed that MdMYB1 could bind directly to the MdGSTF6 promoter to transcriptionally activate its expression.Collectively,our results demonstrate that MdGSTF6 encodes an important GST transporter of anthocyanins in apple fruit and provide evidence for the associated regulatory mechanisms.Therefore,MdMYB1 can not only regulate anthocyanin synthesis,but also control the transport of anthocyanin in apples.This information may be useful for further clarifying the regulation of anthocyanin transport in apple.展开更多
Members of the genus Paeonia,which consists of globally renowned ornamentals and traditional medicinal plants with a rich history spanning over 1500 years,are widely distributed throughout the Northern Hemisphere.Sinc...Members of the genus Paeonia,which consists of globally renowned ornamentals and traditional medicinal plants with a rich history spanning over 1500 years,are widely distributed throughout the Northern Hemisphere.Since 1900,over 2200 new horticultural Paeonia cultivars have been created by the discovery and breeding of wild species.However,information pertaining to Paeonia breeding is considerably fragmented,with fundamental gaps in knowledge,creating a bottleneck in effective breeding strategies.This review systematically introduces Paeonia germplasm resources,including wild species and cultivars,summarizes the breeding strategy and results of each Paeonia cultivar group,and focuses on recent progress in the isolation and functional characterization of structural and regulatory genes related to important horticultural traits.Perspectives pertaining to the resource protection and utilization,breeding and industrialization of Paeonia in the future are also briefly discussed.展开更多
Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.frag...Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.fragrans to assist in studies of the evolution,genetic diversity,and molecular mechanism of aroma development.A total of over 118 Gb of polished reads was produced from HiSeq(45.1 Gb)and PacBio Sequel(73.35 Gb),giving 100×depth coverage for long reads.The combination of Illumina-short reads,PacBio-long reads,and Hi-C data produced the final chromosome quality genome of O.fragrans with a genome size of 727 Mb and a heterozygosity of 1.45%.The genome was annotated using de novo and homology comparison and further refined with transcriptome data.The genome of O.fragrans was predicted to have 45,542 genes,of which 95.68%were functionally annotated.Genome annotation found 49.35%as the repetitive sequences,with long terminal repeats(LTR)being the richest(28.94%).Genome evolution analysis indicated the evidence of whole-genome duplication 15 million years ago,which contributed to the current content of 45,242 genes.Metabolic analysis revealed that linalool,a monoterpene is the main aroma compound.Based on the genome and transcriptome,we further demonstrated the direct connection between terpene synthases(TPSs)and the rich aromatic molecules in O.fragrans.We identified three new flower-specific TPS genes,of which the expression coincided with the production of linalool.Our results suggest that the high number of TPS genes and the flower tissue-and stage-specific TPS genes expressions might drive the strong unique aroma production of O.fragrans.展开更多
Celery(Apium graveolens L.)is a vegetable crop in the Apiaceae family that is widely cultivated and consumed because it contains necessary nutrients and multiple biologically active ingredients,such as apigenin and te...Celery(Apium graveolens L.)is a vegetable crop in the Apiaceae family that is widely cultivated and consumed because it contains necessary nutrients and multiple biologically active ingredients,such as apigenin and terpenoids.Here,we report the genome sequence of celery based on the use of HiSeq 2000 sequencing technology to obtain 600.8 Gb of data,achieving~189-fold genome coverage,from 68 sequencing libraries with different insert sizes ranging from 180 bp to 10 kb in length.The assembled genome has a total sequence length of 2.21 Gb and consists of 34,277 predicted genes.Repetitive DNA sequences represent 68.88%of the genome sequences,and LTR retrotransposons are the main components of the repetitive sequences.Evolutionary analysis showed that a recent whole-genome duplication event may have occurred in celery,which could have contributed to its large genome size.The genome sequence of celery allowed us to identify agronomically important genes involved in disease resistance,flavonoid biosynthesis,terpenoid metabolism,and other important cellular processes.The comparative analysis of apigenin biosynthesis genes among species might explain the high apigenin content of celery.The whole-genome sequences of celery have been deposited at CeleryDB(http://apiaceae.njau.edu.cn/celerydb).The availability of the celery genome data advances our knowledge of the genetic evolution of celery and will contribute to further biological research and breeding in celery as well as other Apiaceae plants.展开更多
The organoleptic qualities of watermelon fruit are defined by the sugar and organic acid contents,which undergo considerable variations during development and maturation.The molecular mechanisms underlying these varia...The organoleptic qualities of watermelon fruit are defined by the sugar and organic acid contents,which undergo considerable variations during development and maturation.The molecular mechanisms underlying these variations remain unclear.In this study,we used transcriptome profiles to investigate the coexpression patterns of gene networks associated with sugar and organic acid metabolism.We identified 3 gene networks/modules containing 2443 genes highly correlated with sugars and organic acids.Within these modules,based on intramodular significance and Reverse Transcription Quantitative polymerase chain reaction(RT-qPCR),we identified 7 genes involved in the metabolism of sugars and organic acids.Among these genes,Cla97C01G000640,Cla97C05G087120 and Cla97C01G018840(r^(2)=0.83 with glucose content)were identified as sugar transporters(SWEET,EDR6 and STP)and Cla97C03G064990(r^(2)=0.92 with sucrose content)was identified as a sucrose synthase from information available for other crops.Similarly,Cla97C07G128420,Cla97C03G068240 and Cla97C01G008870,having strong correlations with malic(r^(2)=0.75)and citric acid(r^(2)=0.85),were annotated as malate and citrate transporters(ALMT7,CS,and ICDH).The expression profiles of these 7 genes in diverse watermelon genotypes revealed consistent patterns of expression variation in various types of watermelon.These findings add significantly to our existing knowledge of sugar and organic acid metabolism in watermelon.展开更多
Auxin signaling,which is crucial for normal plant growth and development,mainly depends on ARF–Aux/IAA interactions.However,little is known regarding the regulatory effects of auxin signaling on anthocyanin metabolis...Auxin signaling,which is crucial for normal plant growth and development,mainly depends on ARF–Aux/IAA interactions.However,little is known regarding the regulatory effects of auxin signaling on anthocyanin metabolism in apple(Malus domestica).We investigated the functions of MdARF13,which contains a repression domain and is localized to the nucleus.This protein was observed to interact with the Aux/IAA repressor,MdIAA121,through its C-terminal dimerization domain.Protein degradation experiments proved that MdIAA121 is an unstable protein that is degraded by the 26S proteasome.Additionally,MdIAA121 stability is affected by the application of exogenous auxin.Furthermore,the overexpression of MdIAA121 and MdARF13 in transgenic red-fleshed apple calli weakened the inhibitory effect of MdARF13 on anthocyanin biosynthesis.These results indicate that the degradation of MdIAA121 induced by auxin treatment can release MdARF13,which acts as a negative regulator of the anthocyanin metabolic pathway.Additionally,yeast two-hybrid,bimolecular fluorescence complementation,and pull-down assays confirmed that MdMYB10 interacts with MdARF13.A subsequent electrophoretic mobility shift assay and yeast one-hybrid assay demonstrated that MdARF13 directly binds to the promoter of MdDFR,which is an anthocyanin pathway structural gene.Interestingly,chromatin immunoprecipitation–quantitative real-time PCR results indicated that the overexpression of MdIAA121 clearly inhibits the recruitment of MdARF13 to the MdDFR promoter.Our findings further characterized the mechanism underlying the regulation of anthocyanin biosynthesis via Aux/IAA–ARF signaling.展开更多
Plants release large amounts of volatile organic compounds(VOCs)in response to attackers.Several VOCs can serve as volatile signals to elicit defense responses in undamaged tissues and neighboring plants,but many ques...Plants release large amounts of volatile organic compounds(VOCs)in response to attackers.Several VOCs can serve as volatile signals to elicit defense responses in undamaged tissues and neighboring plants,but many questions about the ecological functions of VOCs remain unanswered.Tea plants are impacted by two harmful invaders,the piercing herbivore Empoasca(Matsumurasca)onukii Matsuda and the pathogen Colletotrichum fructicola.To determine the VOC signals in tea,we confirmed CsOPR3 as a marker gene and set up a rapid screening method based on a 1.51 kb CsOPR3 promoter fused with aβ-glucuronidase(GUS)reporter construct(OPR3p::GUS)in Arabidopsis.Using this screening system,a terpenoid volatile(E)-nerolidol was identified as a potent signal that elicits plant defenses.The early responses triggered by(E)-nerolidol included the activation of a mitogen-activated protein kinase and WRKY,an H2O2 burst,and the induction of jasmonic acid and abscisic acid signaling.The induced plants accumulated high levels of defenserelated chemicals,which possessed broad-spectrum anti-herbivore or anti-pathogen properties,and ultimately triggered resistance against Empoasca onukii and Colletotrichum fructicola in tea.We propose that these findings can supply an environmentally friendly management strategy for controlling an insect pest and a disease of tea plants.展开更多
Both sorbitol and sucrose are synthesized in source leaves and transported to fruit for supporting fruit growth in tree fruit species of the Rosaceae family.In apple(Malus domestica),antisense suppression of aldose-6-...Both sorbitol and sucrose are synthesized in source leaves and transported to fruit for supporting fruit growth in tree fruit species of the Rosaceae family.In apple(Malus domestica),antisense suppression of aldose-6-phosphate reductase,the key enzyme for sorbitol synthesis,significantly decreased the sorbitol concentration but increased the sucrose concentration in leaves,leading to a lower sorbitol but a higher sucrose supply to fruit in these plants.In response to this altered carbon supply,the transgenic fruit had lower concentration of sorbitol and much higher concentration of glucose but similar levels of fructose,sucrose,and starch throughout fruit development relative to the untransformed control.Activities of sorbitol dehydrogenase,fructokinase,and sucrose phosphate synthase were lower,whereas activities of neutral invertase,sucrose synthase,and hexokinase were higher in the transgenic fruit during fruit development.Transcript levels of MdSOT1,MdSDHs,MdFK2,and MdSPS3/6 were downregulated,whereas transcript levels of MdSUC1/4,MdSUSY1-3,MdNIV1/3,MdHKs,and MdTMT1 were upregulated in the transgenic fruit.These findings suggest that the Sucrose cycle and the sugar transport system are very effective in maintaining the level of fructose and provide insights into the roles of sorbitol and sucrose in regulating sugar metabolism and accumulation in sorbitol-synthesizing species.展开更多
Tea plants(Camellia sinensis)are commercially cultivated in>60 countries,and their fresh leaves are processed into tea,which is the most widely consumed beverage in the world.Although several chromosome-level tea p...Tea plants(Camellia sinensis)are commercially cultivated in>60 countries,and their fresh leaves are processed into tea,which is the most widely consumed beverage in the world.Although several chromosome-level tea plant genomes have been published,they collapsed the two haplotypes and ignored a large number of allelic variations that may underlie important biological functions in this species.Here,we present a phased chromosome-scale assembly for an elite oolong tea cultivar,"Huangdan",that is well known for its high levels of aroma.Based on the two sets of haplotype genome data,we identi fi ed numerous genetic variations and a substantial proportion of allelic imbalance related to important traits,including aroma-and stress-related alleles.Comparative genomics revealed extensive structural variations as well as expansion of some gene families,such as terpene synthases(TPSs),that likely contribute to the high-aroma characteristics of the backbone parent,underlying the molecular basis for the biosynthesis of aroma-related chemicals in oolong tea.Our results uncovered the genetic basis of special features of this oolong tea cultivar,providing fundamental genomic resources to study evolution and domestication for the economically important tea crop.展开更多
基金supported by grants from the Significant Fund of Hebei Province Natural Science Foundation(grant number C2017204114)the National Science and Technology Support Plan of China(2019YFD1001605)the National Ten Thousand Talents Plan Leadership Project,and the Beijing Municipal Education Commission(CEFF-PXM2019_014207_000099).
文摘Jujube(Ziziphus jujuba Mill.),or Chinese date,is the most important species of Rhamnaceae,a large cosmopolitan family,and is one of the oldest cultivated fruit trees in the world.It originates from the middle and lower reaches of the Yellow River,the‘mother river’of the Chinese people.It is distributed in at least 48 countries on all continents except Antarctica and is becoming increasingly important,especially in arid and semiarid marginal lands.Based on a systematic analysis of the unique characteristics of jujube,we suggest that it deserves to be recognized as a superfruit.We summarized historical research achievements from the past 3000 years and reviewed recent research advances since 1949 in seven fields,including genome sequencing and application,germplasm resources and systematic taxonomy,breeding and genetics,cultivation theory and techniques,pest control,postharvest physiology and techniques,and nutrition and processing.Based on the challenges facing the jujube industry,we discuss eight research aspects to be focused on in the future.
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.
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.
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supported by grants from the National Transgenic Science and Technology Program(2019ZX08010-003,2019ZX08010-001)to Y.H.and H.Z.T.Z.is a TIGS postdoctoral fellow.W。
文摘Reporters have been widely used to visualize gene expression,protein localization,and other cellular activities,but the commonly used reporters require special equipment,expensive chemicals,or invasive treatments.Here,we construct a new reporter RUBY that converts tyrosine to vividly red betalain,which is clearly visible to naked eyes without the need of using special equipment or chemical treatments.We show that RUBY can be used to noninvasively monitor gene expression in plants.Furthermore,we show that RUBY is an effective selection marker for transformation events in both rice and Arabidopsis.The new reporter will be especially useful for monitoring cellular activities in large crop plants such as a fruit tree under field conditions and for observing transformation and gene expression in tissue culture under sterile conditions.
基金This research was supported by The National Natural Science Foundation of China(31370688,31400584)the earmarked fund for China Agriculture Research System(CARS-19)+1 种基金Jiangsu Agriculture Science and Technology Innovation Fund(CX(16)1047)Keypoint Research and Invention Program of Jiangsu Province(BE2016417)and FuJian Province“2011 Collaborative Innovation Center”Chinese Oolong Tea Industry Innovation Center(Cultivation)special project(J2015-75).
文摘Purple-leaf tea plants,as anthocyanin-rich cultivars,are valuable materials for manufacturing teas with unique colors or flavors.In this study,a new purple-leaf cultivar“Zixin”(“ZX”)was examined,and its biochemical variation and mechanism of leaf color change were elucidated.The metabolomes of leaves of“ZX”at completely purple,intermediately purple,and completely green stages were analyzed using ultra-performance liquid chromatography quadrupole time of flight mass spectrometry(UPLC-QTOF-MS).Metabolites in the flavonoid biosynthetic pathway remained at high levels in purple leaves,whereas intermediates of porphyrin and chlorophyll metabolism and carotenoid biosynthesis exhibited high levels in green leaves.In addition,fatty acid metabolism was more active in purple leaves,and steroids maintained higher levels in green leaves.Saponin,alcohol,organic acid,and terpenoid-related metabolites also changed significantly during the leaf color change process.Furthermore,the substance changes between“ZX”and“Zijuan”(a thoroughly studied purple-leaf cultivar)were also compared.The leaf color change in“Zijuan”was mainly caused by a decrease in flavonoids/anthocyanins.However,a decrease in flavonoids/anthocyanins,an enhancement of porphyrin,chlorophyll metabolism,carotenoid biosynthesis,and steroids,and a decrease in fatty acids synergistically caused the leaf color change in“ZX”.These findings will facilitate comprehensive research on the regulatory mechanisms of leaf color change in purple-leaf tea cultivars.
基金support from the National Natural Science Foundation of China(31800180)the Natural Science Foundation of Anhui Province(1908085MC75)+5 种基金the National Key Research and Development Program of China(2018YFD1000601)the Science and Technology Project of Anhui Province(13Z03012)the Special Innovative Province Construction in Anhui Province(15czs08032)the Changjiang Scholars and Innovative Research Team in University(IRT1101)the China Postdoctoral Science Foundation(No.2017M621992)the Postdoctoral Science Foundation of Anhui Province,China(No.2017B189).
文摘Tea is among the world’s most widely consumed non-alcoholic beverages and possesses enormous economic,health,and cultural values.It is produced from the cured leaves of tea plants,which are important evergreen crops globally cultivated in over 50 countries.Along with recent innovations and advances in biotechnologies,great progress in tea plant genomics and genetics has been achieved,which has facilitated our understanding of the molecular mechanisms of tea quality and the evolution of the tea plant genome.In this review,we briefly summarize the achievements of the past two decades,which primarily include diverse genome and transcriptome sequencing projects,gene discovery and regulation studies,investigation of the epigenetics and noncoding RNAs,origin and domestication,phylogenetics and germplasm utilization of tea plant as well as newly developed tools/platforms.We also present perspectives and possible challenges for future functional genomic studies that will contribute to the acceleration of breeding programs in tea plants.
基金This work was supported by the National Natural Science Fund for Excellent Young Scientists Fund Program(Overseas)to Y.Z.,the National Key Research and Development Program of China(grant 2019YFA0906200)the Agricultural Science and Technology Innovation Program(CAAS-ZDRW202101)+1 种基金the Shenzhen Science and Technology Program(grant KQTD2016113010482651)the BMBF-funded de.
文摘Grapevine is one of the most economically important crops worldwide.However,the previous versions of the grapevine reference genome tipically consist of thousands of fragments with missing centromeres and telomeres,limiting the accessibility of the repetitive sequences,the centromeric and telomeric regions,and the study of inheritance of important agronomic traits in these regions.Here,we assembled a telomere-to-telomere(T2T)gap-free reference genome for the cultivar PN40024 using PacBio HiFi long reads.The T2T reference genome(PN_T2T)is 69 Mb longer with 9018 more genes identified than the 12X.v0 version.We annotated 67%repetitive sequences,19 centromeres and 36 telomeres,and incorporated gene annotations of previous versions into the PN_T2T assembly.We detected a total of 377 gene clusters,which showed associations with complex traits,such as aroma and disease resistance.Even though PN40024 derives from nine generations of selfing,we still found nine genomic hotspots of heterozygous sites associated with biological processes,such as the oxidation–reduction process and protein phosphorylation.The fully annotated complete reference genome therefore constitutes an important resource for grapevine genetic studies and breeding programs.
基金supported by National Natural Science Foundation of China(31701924)the National Science Foundation(US IOS 0957264)+1 种基金Fundamental Research Funds for the Central Universities,China(KYZ201609)the US NSF support to ALTP(IOS 0544504 and 0957264).
文摘Fruit cracking is an important problem in horticultural crop production.Polygalacturonase(SlPG)and expansin(SlEXP1)proteins cooperatively disassemble the polysaccharide network of tomato fruit cell walls during ripening and thereby,enable softening.A Golden 2-like(GLK2)transcription factor,SlGLK2 regulates unripe fruit chloroplast development and results in elevated soluble solids and carotenoids in ripe fruit.To determine whether SlPG,SlEXP1,or SlGLK2 influence the rate of tomato fruit cracking,the incidence of fruit epidermal cracking was compared between wild-type,Ailsa Craig(WT)and fruit with suppressed SlPG and SlEXP1 expression(pg/exp)or expressing a truncated nonfunctional Slglk2(glk2).Treating plants with exogenous ABA increases xylemic flow into fruit.Our results showed that ABA treatment of tomato plants greatly increased cracking of fruit from WT and glk2 mutant,but not from pg/exp genotypes.The pg/exp fruit were firmer,had higher total soluble solids,denser cell walls and thicker cuticles than fruit of the other genotypes.Fruit from the ABA treated pg/exp fruit had cell walls with less water-soluble and more ionically and covalently-bound pectins than fruit from the other lines,demonstrating that ripening-related disassembly of the fruit cell wall,but not elimination of SlGLK2,influences cracking.Cracking incidence was significantly correlated with cell wall and wax thickness,and the content of cell wall protopectin and cellulose,but not with Ca^(2+)content.
基金the Central Public-interest Scientific Institution Basal Research Fund for the Chinese Academy of Tropical Agricultural Sciences(No.1630092020003)Integrated Demonstration of Key Techniques for the Industrial Development of Featured Crops in Rocky Desertification Areas of Yunnan-Guangxi-Guizhou Provinces(SMH2019-2021)+1 种基金the Central Public-interest Scientific Institution Basal Research Fund for the Chinese Academy of Tropical Agricultural Sciences(No.1630052019022)the Foundation of the State Key Laboratory of Biobased Material and Green Papermaking(No.23190444).
文摘Passion fruit(Passiflora edulis Sims)is an economically valuable fruit that is cultivated in tropical and subtropical regions of the world.Here,we report an~1341.7Mb chromosome-scale genome assembly of passion fruit,with 98.91%(~1327.18Mb)of the assembly assigned to nine pseudochromosomes.The genome includes 23,171 protein-coding genes,and most of the assembled sequences are repetitive sequences,with long-terminal repeats(LTRs)being the most abundant.Phylogenetic analysis revealed that passion fruit diverged after Brassicaceae and before Euphorbiaceae.Ks analysis showed that two whole-genome duplication events occurred in passion fruit at 65 MYA and 12 MYA,which may have contributed to its large genome size.An integrated analysis of genomic,transcriptomic,and metabolomic data showed that‘alpha-linolenic acid metabolism’,‘metabolic pathways’,and‘secondary metabolic pathways’were the main pathways involved in the synthesis of important volatile organic compounds(VOCs)in passion fruit,and this analysis identified some candidate genes,including GDP-fucose Transporter 1-like,Tetratricopeptide repeat protein 33,protein NETWORKED 4B isoform X1,and Golgin Subfamily A member 6-like protein 22.In addition,we identified 13 important gene families in fatty acid pathways and eight important gene families in terpene pathways.Gene family analysis showed that the ACX,ADH,ALDH,and HPL gene families,especially ACX13/14/15/20,ADH13/26/33,ALDH1/4/21,and HPL4/6,were the key genes for ester synthesis,while the TPS gene family,especially PeTPS2/3/4/24,was the key gene family for terpene synthesis.This work provides insights into genome evolution and flavor trait biology and offers valuable resources for the improved cultivation of passion fruit.
基金supported by the National Natural Science Foundation of China(No.31730080,No.31572091)the Ministry of Science and Technology Key Research and Development Plan(No.SQ2016YFSF030011).
文摘Anthocyanins are biosynthesized on the cytosolic surface of the endoplasmic reticulum and then transported into the vacuole for storage.Glutathione S-transferases(GSTs)are considered to be responsible for the transport of anthocyanins into the vacuole.However,the regulatory mechanisms of GSTs in plants are still unclear.Here,we performed a genome-wide analysis and identified 69 GST genes in apple.The expression of MdGSTF6 was positively correlated with the anthocyanin content(r=0.949)during‘Yanfu 8’fruit development.The overexpression of MdGSTF6 in the Arabidopsis thaliana tt19 mutant resulted in seedlings of 35S::MdGSTF6-GFP/tt19 that could accumulate anthocyanin and rescue its phenotype,suggesting that MdGSTF6 was an anthocyanin transporter.The silencing of MdGSTF6 affected anthocyanin accumulation in apple fruit.Moreover,the knockdown of MdGSTF6 by RNA interference in cultured‘Gala’seedlings inhibited anthocyanin accumulation.The interaction experiments showed that MdMYB1 could bind directly to the MdGSTF6 promoter to transcriptionally activate its expression.Collectively,our results demonstrate that MdGSTF6 encodes an important GST transporter of anthocyanins in apple fruit and provide evidence for the associated regulatory mechanisms.Therefore,MdMYB1 can not only regulate anthocyanin synthesis,but also control the transport of anthocyanin in apples.This information may be useful for further clarifying the regulation of anthocyanin transport in apple.
基金supported by the National Key R&D Program of China(2018YFD1000406)the National Natural Science Foundation of China(31772350).
文摘Members of the genus Paeonia,which consists of globally renowned ornamentals and traditional medicinal plants with a rich history spanning over 1500 years,are widely distributed throughout the Northern Hemisphere.Since 1900,over 2200 new horticultural Paeonia cultivars have been created by the discovery and breeding of wild species.However,information pertaining to Paeonia breeding is considerably fragmented,with fundamental gaps in knowledge,creating a bottleneck in effective breeding strategies.This review systematically introduces Paeonia germplasm resources,including wild species and cultivars,summarizes the breeding strategy and results of each Paeonia cultivar group,and focuses on recent progress in the isolation and functional characterization of structural and regulatory genes related to important horticultural traits.Perspectives pertaining to the resource protection and utilization,breeding and industrialization of Paeonia in the future are also briefly discussed.
基金This work was supported by research grants provided by the National Natural Science Foundation(31870695 and 31601785)the Project of Key Research and Development Plan(Modern Agriculture)in Jiangsu(BE2017375)+1 种基金the Selection and Breeding of Excellent Tree Species and Effective Cultivation Techniques(CX(16)1005)the Project of Osmanthus National Germplasm Bank,and the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions.
文摘Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.fragrans to assist in studies of the evolution,genetic diversity,and molecular mechanism of aroma development.A total of over 118 Gb of polished reads was produced from HiSeq(45.1 Gb)and PacBio Sequel(73.35 Gb),giving 100×depth coverage for long reads.The combination of Illumina-short reads,PacBio-long reads,and Hi-C data produced the final chromosome quality genome of O.fragrans with a genome size of 727 Mb and a heterozygosity of 1.45%.The genome was annotated using de novo and homology comparison and further refined with transcriptome data.The genome of O.fragrans was predicted to have 45,542 genes,of which 95.68%were functionally annotated.Genome annotation found 49.35%as the repetitive sequences,with long terminal repeats(LTR)being the richest(28.94%).Genome evolution analysis indicated the evidence of whole-genome duplication 15 million years ago,which contributed to the current content of 45,242 genes.Metabolic analysis revealed that linalool,a monoterpene is the main aroma compound.Based on the genome and transcriptome,we further demonstrated the direct connection between terpene synthases(TPSs)and the rich aromatic molecules in O.fragrans.We identified three new flower-specific TPS genes,of which the expression coincided with the production of linalool.Our results suggest that the high number of TPS genes and the flower tissue-and stage-specific TPS genes expressions might drive the strong unique aroma production of O.fragrans.
基金supported by the Jiangsu Agriculture Science and Technology Innovation Fund(CX(18)2007)New Century Excellent Talents in University(NCET-11-0670)National Natural Science Foundation of China。
文摘Celery(Apium graveolens L.)is a vegetable crop in the Apiaceae family that is widely cultivated and consumed because it contains necessary nutrients and multiple biologically active ingredients,such as apigenin and terpenoids.Here,we report the genome sequence of celery based on the use of HiSeq 2000 sequencing technology to obtain 600.8 Gb of data,achieving~189-fold genome coverage,from 68 sequencing libraries with different insert sizes ranging from 180 bp to 10 kb in length.The assembled genome has a total sequence length of 2.21 Gb and consists of 34,277 predicted genes.Repetitive DNA sequences represent 68.88%of the genome sequences,and LTR retrotransposons are the main components of the repetitive sequences.Evolutionary analysis showed that a recent whole-genome duplication event may have occurred in celery,which could have contributed to its large genome size.The genome sequence of celery allowed us to identify agronomically important genes involved in disease resistance,flavonoid biosynthesis,terpenoid metabolism,and other important cellular processes.The comparative analysis of apigenin biosynthesis genes among species might explain the high apigenin content of celery.The whole-genome sequences of celery have been deposited at CeleryDB(http://apiaceae.njau.edu.cn/celerydb).The availability of the celery genome data advances our knowledge of the genetic evolution of celery and will contribute to further biological research and breeding in celery as well as other Apiaceae plants.
基金supported by the Agricultural Science and Technology Innovation Program(CAAS-ASTIP-2016-ZFRI)National Key R&D Program of China(2018YFD0100704)the China Agriculture Research System(CARS-25-03)+1 种基金National Natural Science Foundation of China[31672178&31471893]Scientific and Technological Project of Henan Province(202102110197).
文摘The organoleptic qualities of watermelon fruit are defined by the sugar and organic acid contents,which undergo considerable variations during development and maturation.The molecular mechanisms underlying these variations remain unclear.In this study,we used transcriptome profiles to investigate the coexpression patterns of gene networks associated with sugar and organic acid metabolism.We identified 3 gene networks/modules containing 2443 genes highly correlated with sugars and organic acids.Within these modules,based on intramodular significance and Reverse Transcription Quantitative polymerase chain reaction(RT-qPCR),we identified 7 genes involved in the metabolism of sugars and organic acids.Among these genes,Cla97C01G000640,Cla97C05G087120 and Cla97C01G018840(r^(2)=0.83 with glucose content)were identified as sugar transporters(SWEET,EDR6 and STP)and Cla97C03G064990(r^(2)=0.92 with sucrose content)was identified as a sucrose synthase from information available for other crops.Similarly,Cla97C07G128420,Cla97C03G068240 and Cla97C01G008870,having strong correlations with malic(r^(2)=0.75)and citric acid(r^(2)=0.85),were annotated as malate and citrate transporters(ALMT7,CS,and ICDH).The expression profiles of these 7 genes in diverse watermelon genotypes revealed consistent patterns of expression variation in various types of watermelon.These findings add significantly to our existing knowledge of sugar and organic acid metabolism in watermelon.
基金This work was supported by grants from the National Key Research Project(2016YFC0501505)the National Natural Science Foundation of China(31572091 and 31730080).
文摘Auxin signaling,which is crucial for normal plant growth and development,mainly depends on ARF–Aux/IAA interactions.However,little is known regarding the regulatory effects of auxin signaling on anthocyanin metabolism in apple(Malus domestica).We investigated the functions of MdARF13,which contains a repression domain and is localized to the nucleus.This protein was observed to interact with the Aux/IAA repressor,MdIAA121,through its C-terminal dimerization domain.Protein degradation experiments proved that MdIAA121 is an unstable protein that is degraded by the 26S proteasome.Additionally,MdIAA121 stability is affected by the application of exogenous auxin.Furthermore,the overexpression of MdIAA121 and MdARF13 in transgenic red-fleshed apple calli weakened the inhibitory effect of MdARF13 on anthocyanin biosynthesis.These results indicate that the degradation of MdIAA121 induced by auxin treatment can release MdARF13,which acts as a negative regulator of the anthocyanin metabolic pathway.Additionally,yeast two-hybrid,bimolecular fluorescence complementation,and pull-down assays confirmed that MdMYB10 interacts with MdARF13.A subsequent electrophoretic mobility shift assay and yeast one-hybrid assay demonstrated that MdARF13 directly binds to the promoter of MdDFR,which is an anthocyanin pathway structural gene.Interestingly,chromatin immunoprecipitation–quantitative real-time PCR results indicated that the overexpression of MdIAA121 clearly inhibits the recruitment of MdARF13 to the MdDFR promoter.Our findings further characterized the mechanism underlying the regulation of anthocyanin biosynthesis via Aux/IAA–ARF signaling.
基金sponsored by the Central Public-interest Scientific Institution Basal Research Fund(1610212016019 and 1610212018015)the Modern Agricultural Industry Technology System(CARS-23)the National Natural Science Foundation of China(31401758).
文摘Plants release large amounts of volatile organic compounds(VOCs)in response to attackers.Several VOCs can serve as volatile signals to elicit defense responses in undamaged tissues and neighboring plants,but many questions about the ecological functions of VOCs remain unanswered.Tea plants are impacted by two harmful invaders,the piercing herbivore Empoasca(Matsumurasca)onukii Matsuda and the pathogen Colletotrichum fructicola.To determine the VOC signals in tea,we confirmed CsOPR3 as a marker gene and set up a rapid screening method based on a 1.51 kb CsOPR3 promoter fused with aβ-glucuronidase(GUS)reporter construct(OPR3p::GUS)in Arabidopsis.Using this screening system,a terpenoid volatile(E)-nerolidol was identified as a potent signal that elicits plant defenses.The early responses triggered by(E)-nerolidol included the activation of a mitogen-activated protein kinase and WRKY,an H2O2 burst,and the induction of jasmonic acid and abscisic acid signaling.The induced plants accumulated high levels of defenserelated chemicals,which possessed broad-spectrum anti-herbivore or anti-pathogen properties,and ultimately triggered resistance against Empoasca onukii and Colletotrichum fructicola in tea.We propose that these findings can supply an environmentally friendly management strategy for controlling an insect pest and a disease of tea plants.
基金This work was supported in part by the National Natural Science Foundation of China(No.31372038 to M.L.)Cornell Agricultural Experiment Station.
文摘Both sorbitol and sucrose are synthesized in source leaves and transported to fruit for supporting fruit growth in tree fruit species of the Rosaceae family.In apple(Malus domestica),antisense suppression of aldose-6-phosphate reductase,the key enzyme for sorbitol synthesis,significantly decreased the sorbitol concentration but increased the sucrose concentration in leaves,leading to a lower sorbitol but a higher sucrose supply to fruit in these plants.In response to this altered carbon supply,the transgenic fruit had lower concentration of sorbitol and much higher concentration of glucose but similar levels of fructose,sucrose,and starch throughout fruit development relative to the untransformed control.Activities of sorbitol dehydrogenase,fructokinase,and sucrose phosphate synthase were lower,whereas activities of neutral invertase,sucrose synthase,and hexokinase were higher in the transgenic fruit during fruit development.Transcript levels of MdSOT1,MdSDHs,MdFK2,and MdSPS3/6 were downregulated,whereas transcript levels of MdSUC1/4,MdSUSY1-3,MdNIV1/3,MdHKs,and MdTMT1 were upregulated in the transgenic fruit.These findings suggest that the Sucrose cycle and the sugar transport system are very effective in maintaining the level of fructose and provide insights into the roles of sorbitol and sucrose in regulating sugar metabolism and accumulation in sorbitol-synthesizing species.
基金This research was funded by the Fujian Province"2011 Collaborative Innovation Center",the Chinese Oolong Tea Industry Innovation Center special project(J 2015-75)the National Natural Science Foundation of China(31701874)+3 种基金the Major Special Project of Scientific and Technological Innovation on Anxi Tea(AX2021001)the Earmarked Fund for the China Agriculture Research System(CARS-19)the Scientific Research Foundation of the Graduate School of Fujian Agriculture and Forestry University(324-1122yb060)the Scientific Research Foundation of Horticulture College of Fujian Agriculture and Forestry University(2018B02).
文摘Tea plants(Camellia sinensis)are commercially cultivated in>60 countries,and their fresh leaves are processed into tea,which is the most widely consumed beverage in the world.Although several chromosome-level tea plant genomes have been published,they collapsed the two haplotypes and ignored a large number of allelic variations that may underlie important biological functions in this species.Here,we present a phased chromosome-scale assembly for an elite oolong tea cultivar,"Huangdan",that is well known for its high levels of aroma.Based on the two sets of haplotype genome data,we identi fi ed numerous genetic variations and a substantial proportion of allelic imbalance related to important traits,including aroma-and stress-related alleles.Comparative genomics revealed extensive structural variations as well as expansion of some gene families,such as terpene synthases(TPSs),that likely contribute to the high-aroma characteristics of the backbone parent,underlying the molecular basis for the biosynthesis of aroma-related chemicals in oolong tea.Our results uncovered the genetic basis of special features of this oolong tea cultivar,providing fundamental genomic resources to study evolution and domestication for the economically important tea crop.
