Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars bas...Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this disease.The traditional way of R gene functional validation requires stable transformation that is both time-and labor-consuming.In this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was developed.The transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable transformation.The system was applicable to different B.napus varieties and other cruciferous crops including Brassica rapa and Brassica oleracea.In particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent P.brassicae infection in B.napus.Most importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible phenotype.Therefore,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the P.brassicae genome that could improve our knowledge on host-pathogen interaction.展开更多
[Objectives]The paper was to explore the occurrence and mixed infection of sugarcane bacilliform virus disease in Hainan sugarcane-growing area.[Methods]A total of 348 sugarcane leaf samples were collected from 7 suga...[Objectives]The paper was to explore the occurrence and mixed infection of sugarcane bacilliform virus disease in Hainan sugarcane-growing area.[Methods]A total of 348 sugarcane leaf samples were collected from 7 sugarcane-growing areas in Hainan Province.Molecular detection of sugarcane bacilliform virus(SCBV)was carried out by PCR using specific primers.[Results]SCBV was detected in 244 out of 348 sugarcane samples,with an average detection rate of 70.11%.The highest detection rate was 76.66%in the Danzhou sugarcane-growing area,while the lowest was 57.14%in the Baisha sugarcane-growing area.The SCBV-positive samples were subjected to testing for SCYLV,SCSMV,SrMV,and SCMV,respectively.The results indicated that 106 out of 244 positive samples exhibited a single infection with SCBV,while 138 samples exhibited mixed infections with SCBV and other sugarcane viruses.The proportion of mixed infections among the SCBV-positive samples was as high as 56.56%.Among the various types of mixed infections,two-virus and three-virus mixed infections were the most prevalent.[Conclusions]SCBV has emerged as a significant threat to the secure production of sugarcane in the Hainan sugarcane-growing region.It presents an explosive infection in the Hainan sugarcane-growing region and frequently combines with other sugarcane viruses to infect sugarcane.The findings of this study will provide a theoretical foundation for the prevention and control of sugarcane bacilliform virus disease.展开更多
The high content of cyanogenic glycosides(CG)in cassava tubers affects food safety.CG are involved in the plant growth and development and protect cassava leaves from herbivorous predators.However,the regulatory mecha...The high content of cyanogenic glycosides(CG)in cassava tubers affects food safety.CG are involved in the plant growth and development and protect cassava leaves from herbivorous predators.However,the regulatory mechanism of CG biosynthesis remains poorly understood.Here,yeast one-hybrid assays were performed using a mixed cDNA library of cassava tubers and leaves as prey and the promoter of MeCYP79D2 as bait.MeCYP79D2,a cytochrome P450 protein,is the rate-limiting enzyme for CG synthesis in cassava.From this information,a candidate regulator of MeCYP79D2 was selected and identified as transcription factor MePHD1.2.MePHD1.2,located in the nucleus and exhibiting an inhibitory transcription activity directly bound to an AT-rich motif in the promoter of MeCYP79D2.In cassava,the transcriptional activity of MeCYP79D2 was considerably enhanced in mephd1.2 mutant lines leading to increased linamarin and lotaustralin contents.Deletion of MePHD1.2 promoted the production of CGs in cassava and decreased transcription inhibition on MeCYP79D2,exposing a novel regulatory module governing biosynthesis of CGs.展开更多
Litchi(Litchi chinensis Sonn.)is a type of commercially prevalent subtropical and tropical fruit.Since litchi has a highly heterozygous genetic background and a long reproductive cycle,conventional breeding methods(su...Litchi(Litchi chinensis Sonn.)is a type of commercially prevalent subtropical and tropical fruit.Since litchi has a highly heterozygous genetic background and a long reproductive cycle,conventional breeding methods(such as hybridization)have limited ability to nurture new litchi cultivars.Here,an efficient and stable Agrobacterium tumefaciens-mediated genetic transformation of embryogenic callus was established in‘Feizixiao’litchi.Transgenic materials were verified using polymerase chain reaction(PCR)analysis,β-glucuronidase(GUS)assay,and green fluorescent protein(GFP)assay.To implement the technology of the Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)/associated protein 9(CRISPR/Cas9)technology in‘Feizixiao’litchi and verify the validity of these transformation systems,the litchi polyphenol oxidase gene(LcPPO,JF926153)was knocked out.Various categories of mutations,covering base insertions,deletions,and substitutions,were found in transgenic materials via sequence analysis.The transformation system achieved high feasibility and efficiency,and the system of CRISPR/Cas9 was successfully employed to edit genes in‘Feizixiao’litchi.This work provides an essential foundation for investigating the functions of genes and accelerating litchi genetic improvement.展开更多
Passion fruit(Passiflora edulis Sims) is a vine of the Passiflora genus in the Passifloraceae family. The extracted components include flavonoids and terpenoids, which have good anti-anxiety and anti-inflammatory effe...Passion fruit(Passiflora edulis Sims) is a vine of the Passiflora genus in the Passifloraceae family. The extracted components include flavonoids and terpenoids, which have good anti-anxiety and anti-inflammatory effects in humans.In this study, we analyzed the transcriptomes of four tissues of the ‘Zixiang’ cultivar using RNA-Seq, which provided a dataset for functional gene mining. The de novo assembly of these reads generated 96 883 unigenes, among which 61 022 unigenes were annotated(62.99% yield). In addition to its edible value, another important application of passion fruit is its medicinal value. The flavonoids and terpenoids are mainly derivatives of luteolin, apigenin, cycloartane triterpenoid saponins and other active substances in leaf extracts. A series of candidate unigenes in the transcriptome data that are potentially involved in the flavonoid and terpenoid synthesis pathways were screened using homologybased BLAST and phylogenetic analysis. The results showed that the biosynthesis of triterpenoids in passion fruit comes from the branches of the mevalonate(MVA) and 2-C-methyl-D-erythritol 4-phosphate/1-deoxy-D-xylulose 5-phosphate(MEP/DOXP) pathways, which is different from the MVA pathway that is used in other fruit trees. Most of the candidate genes were found to be highly expressed in the leaves and/or flowers. Quantitative real-time PCR(qRT-PCR) verification was carried out and confirmed the reliability of the RNA-Seq data. Further amplification and functional analysis of these putative unigenes will provide additional insight into the biosynthesis of flavonoids and terpenoids in passion fruit.展开更多
WRKY transcription factors,transcriptional regulators unique to plants,play an important role in defense response to pathogen infection.However,the resistance mechanisms of WRKY genes in sugarcane remain unclear.In th...WRKY transcription factors,transcriptional regulators unique to plants,play an important role in defense response to pathogen infection.However,the resistance mechanisms of WRKY genes in sugarcane remain unclear.In the present study,gene ontology(GO)enrichment analysis revealed that WRKY gene family in sugarcane was extensively involved in the response to biotic stress and in defense response.We identified gene ScWRKY4,a classⅡc member of the WRKY gene family,in sugarcane cultivar ROC22.This gene was induced by salicylic acid(SA)and methyl jasmonate(MeJA)stress.Interestingly,expression of ScWRKY4 was down-regulated in smut-resistant sugarcane cultivars but up-regulated in smutsusceptible sugarcane cultivars infected with Sporisorium scitamineum.Moreover,stable overexpression of the ScWRKY4 gene in Nicotiana benthamiana enhanced susceptibility to Fusarium solani var.coeruleum and caused down-regulated expression of immune marker-related genes.Transcriptome analysis indicated suppressed expression of most JAZ genes in the signal transduction pathway.ScWRKY4 interacted with ScJAZ13 to repress its expression.We thus hypothesized that the ScWRKY4 gene was involved in the regulatory network of plant disease resistance,most likely through the JA signaling pathway.The present study depicting the molecular involvement of ScWRKY4 in sugarcane disease resistance lays a foundation for future investigation.展开更多
Drought stress impairs plant growth and other physiological functions. MeHDZ14, a homeodomainleucine zipper I transcription factor, is strongly induced by drought stress in various cassava cultivars.However, the role ...Drought stress impairs plant growth and other physiological functions. MeHDZ14, a homeodomainleucine zipper I transcription factor, is strongly induced by drought stress in various cassava cultivars.However, the role of MeHDZ14 in cassava growth regulation has remained unclear. Here we report that MeHDZ14 affected plant height, such that a dwarf phenotype and altered internode elongation were observed in transgenic cassava lines. MeHDZ14 was found to negatively regulate the biosynthesis of lignin. Its overexpression resulted in abaxially rolled leaves. The morphogenesis of leaf epidermal cells was inhibited by overexpression of MeHDZ14, with decreased auxin and gibberellin and increased cytokinin contents. MeHDZ14 was found to regulate many drought-responsive genes, including genes involved in cell wall synthesis and expansion. MeHDZ14 bound to the promoter of caffeic acid 3-Omethyltransferase 1(MeCOMT1), acting as a transcriptional repressor of genes involved in cell wall development. MeHDZ14 appears to act as a negative regulator of internode elongation and epidermal cell morphogenesis during cassava leaf development.展开更多
Chilling-induced accumulation of reactive oxygen species(ROS) is harmful to plants,which usually produce anthocyanins to scavenge ROS as protection from chilling stress.As a tropical crop,cassava is hypersensitive to ...Chilling-induced accumulation of reactive oxygen species(ROS) is harmful to plants,which usually produce anthocyanins to scavenge ROS as protection from chilling stress.As a tropical crop,cassava is hypersensitive to chilling,but the biochemical basis of this hypersensitivity remains unclear.We previously generated Me MYB2-RNAi transgenic cassava with increased chilling tolerance.Here we report that Me MYB2-RNAi transgenic cassava accumulated less ROS but more cyanidin-3-O-glucoside than the wild type under early chilling stress.Under this stress,the anthocyanin biosynthesis pathway was more active in Me MYB2-RNAi lines than in the wild type,and several genes involved in the pathway,including Me TT8,were up-regulated by Me MYB2-RNAi in the transgenic cassava.Me MYB2 bound to the Me TT8 promoter and blocked its expression under both normal and chilling conditions,thereby inhibiting anthocyanin accumulation.Me TT8 was shown to bind to the promoter of Dihydroflavonol 4-reductase(Me DFR-2)and increased Me DFR-2 expression.Me MYB2 appears to act as an inhibitor of chilling-induced anthocyanin accumulation during the rapid response of cassava to chilling stress.展开更多
In plants,5mC DNA methylation is an important and conserved epistatic mark involving genomic stability,gene transcriptional regulation,developmental regulation,abiotic stress response,metabolite synthesis,etc.However,...In plants,5mC DNA methylation is an important and conserved epistatic mark involving genomic stability,gene transcriptional regulation,developmental regulation,abiotic stress response,metabolite synthesis,etc.However,the roles of 5mC DNA methylation modification(5mC methylation)in tea plant growth and development(in pre-harvest processing)and flavor substance synthesis in pre-and post-harvest processing are unknown.We therefore conducted a comprehensive methylation analysis of four key pre-harvest tissues(root,leaf,flower,and fruit)and two processed leaves during oolong tea post-harvest processing.We found that differential 5mC methylation among four key tissues is closely related to tissue functional differentiation and that genes expressed tissue-specifically,responsible for tissue-specific functions,maintain relatively low 5mC methylation levels relative to non-tissue-specifically expressed genes.Importantly,hypomethylation modifications of CsAlaDC and TS/GS genes in roots provided the molecular basis for the dominant synthesis of theanine in roots.In addition,integration of 5mC DNA methylationomics,metabolomics,and transcriptomics of post-harvest leaves revealed that content changes in flavor metabolites during oolong tea processing were closely associated with transcription level changes in corresponding metabolite synthesis genes,and changes in transcript levels of these important synthesis genes were strictly regulated by 5mC methylation.We further report that some key genes during processing are regulated by 5mC methylation,which can effectively explain the content changes of important aroma metabolites,includingα-farnesene,nerolidol,lipids,and taste substances such as catechins.Our results not only highlight the key roles of 5mC methylation in important flavor substance synthesis in pre-and post-harvest processing,but also provide epimutation-related gene targets for future improvement of tea quality or breeding of whole-tissue high-theanine varieties.展开更多
Dear Editor,Tea plant(Camellia sinensis(L.)O.Kuntze)is one of the world’s most important non-alcoholic beverages,with great economic,health,and cultural value.Recently,several genomes of C.sinensis var.assamica(CSA)(...Dear Editor,Tea plant(Camellia sinensis(L.)O.Kuntze)is one of the world’s most important non-alcoholic beverages,with great economic,health,and cultural value.Recently,several genomes of C.sinensis var.assamica(CSA)(Yunkang 10),C.sinensis var.sinensis(CSS)(Shuchazao,Biyun,Longjing 43,Tieguanyin,Huangdan),and ancient tea plant(DASZ)have been deciphered[1-3].展开更多
Sugarcane is recognized as the fifth largest crop globally,supplying 80%of sugar and 40%of bioenergy production.However,sugarcane genetic research has significantly lagged behind other crops due to its complex genetic...Sugarcane is recognized as the fifth largest crop globally,supplying 80%of sugar and 40%of bioenergy production.However,sugarcane genetic research has significantly lagged behind other crops due to its complex genetic background,high ploidy(8-13×),aneuploidy,limited flowering,and a long growth cycle(more than one year).Cross breeding began in 1887 following the discovery that sugarcane seeds could germinate.Both self-and cross-pollination and selection were conducted by sugarcane breeders,but new cultivars were often eliminated due to disease susceptibility.Within the Saccharum genus,different species possess variable numbers of chromosomes.Wild sugarcane species intercrossed with each other,leading to development of the‘Nobilization’breeding strategy,which significantly improved yield,sucrose,fiber content,and disease resistance,and accelerated genetic improvement of cultivars.In recent years,scientific achievements have also been made in sugarcane genome sequencing,molecular marker development,genetic linkage map construction,localization of quantitative trait locus(QTL),and trait-associated gene identification.This review focuses on the progress in sugarcane genetic research,analyzes the technical difficulties faced,presents opportunities and challenges,and provides guidance and references for future sugarcane genetics research and cultivar breeding.Finally,it offers directions for future on sugarcane genetics.展开更多
Addressing global challenges such as energy sustainability,food security,and environmental conservation requires innovative agricultural solutions.Modern sugarcane(Saccharum hybrid)is a crucial crop that contributes n...Addressing global challenges such as energy sustainability,food security,and environmental conservation requires innovative agricultural solutions.Modern sugarcane(Saccharum hybrid)is a crucial crop that contributes not only to the sugar industry but also to bioenergy systems.Beyond its traditional role,sugarcane supports global food security,environmental sustainability,and economic empowerment of farmers.Over 80%of the worldwide sugarcane production is dedicated to sugar,a dietary staple(OECD-FAO,2024).The remaining 19%aid biofuel production,with sugarcane accounting for 24%of the global ethanol feedstock by 2033.As a C4 plant,sugarcane efficiently captures atmospheric carbon and acts as an important carbon sink.Additionally,sugarcane cultivation can lower local temperatures by nearly 1°C compared to pastures/natural vegetation(Loarie et al.,2011).Economically,sugarcane is a high-value cash crop,generating$43 billion annually in Brazil alone(Voora et al.,2023).展开更多
Pineapple is the third most crucial tropical fruit worldwide and available in five varieties.Genomes of different pineapple varieties have been released to date;however,none of them are complete,with all exhibiting su...Pineapple is the third most crucial tropical fruit worldwide and available in five varieties.Genomes of different pineapple varieties have been released to date;however,none of them are complete,with all exhibiting substantial gaps and representing only two of the five pineapple varieties.This significantly hinders the advancement of pineapple breeding efforts.In this study,we sequenced the genomes of three varieties:a wild pineapple variety,a fiber pineapple variety,and a globally cultivated edible pineapple variety.We constructed the first gap-free reference genome(Ref)for pineapple.By consolidating multiple sources of evidence and manually revising each gene structure annotation,we identified 26,656 proteincoding genes.The BUSCO evaluation indicated a completeness of 99.2%,demonstrating the high quality of the gene structure annotations in this genome.Utilizing these resources,we identified 7,209 structural variations across the three varieties.Approximately 30.8%of pineapple genes were located within±5 kb of structural variations,including 30 genes associated with anthocyanin synthesis.Further analysis and functional experiments demonstrated that the high expression of AcMYB528 aligns with the accumulation of anthocyanins in the leaves,both of which may be affected by a 1.9-kb insertion fragment.In addition,we developed the Ananas Genome Database,which offers data browsing,retrieval,analysis,and download functions.The construction of this database addresses the lack of pineapple genome resource databases.In summary,we acquired a seamless pineapple reference genome with highquality gene structure annotations,providing a solid foundation for pineapple genomics and a valuable reference for pineapple breeding.展开更多
基金supported by grants from the Wuhan Science and Technology Major Project on Key techniques of biological breeding and Breeding of new varieties(Grant No.2022021302024851)the special project for sustainable development agenda of innovation demonstration zone(Grant No.202204AC100001-A04)the National Key R&D Program of China(Grant No.2022YFD1200400)。
文摘Many economically important crops and vegetables belonging to the cruciferous family are heavily endangered by clubroot disease caused by Plasmodiophora brassicae infection.Breeding of clubroot resistant cultivars based on mapping and cloning of resistant genes is commonly regarded as the most cost-effective and efficient way to fight against this disease.The traditional way of R gene functional validation requires stable transformation that is both time-and labor-consuming.In this study,a rapid and efficient hairy-root transgenic protocol mediated by Agrobacterium rhizogenes was developed.The transformation positive rate was over 80%in Brassica napus showed by GUS reporter gene and this transformation only took 1/6 of the time compared with stable transformation.The system was applicable to different B.napus varieties and other cruciferous crops including Brassica rapa and Brassica oleracea.In particular,two known CR genes,CRA3.7.1 and CRA8.2.4 were used respectively,as example to show that the system works well for CR gene study combined with subsequent P.brassicae infection in B.napus.Most importantly,it works both in over-expression that led to disease resistance,as well as in RNAi which led to disease susceptible phenotype.Therefore,this system can be used in batch-wise identification of CR genes,and also offered the possibility of manipulating key genes within the P.brassicae genome that could improve our knowledge on host-pathogen interaction.
基金Supported by Hainan Provincial Natural Science Foundation of China(321QN313,323MS103)Earmarked Fund for China Agricultural Research System(CARS-17).
文摘[Objectives]The paper was to explore the occurrence and mixed infection of sugarcane bacilliform virus disease in Hainan sugarcane-growing area.[Methods]A total of 348 sugarcane leaf samples were collected from 7 sugarcane-growing areas in Hainan Province.Molecular detection of sugarcane bacilliform virus(SCBV)was carried out by PCR using specific primers.[Results]SCBV was detected in 244 out of 348 sugarcane samples,with an average detection rate of 70.11%.The highest detection rate was 76.66%in the Danzhou sugarcane-growing area,while the lowest was 57.14%in the Baisha sugarcane-growing area.The SCBV-positive samples were subjected to testing for SCYLV,SCSMV,SrMV,and SCMV,respectively.The results indicated that 106 out of 244 positive samples exhibited a single infection with SCBV,while 138 samples exhibited mixed infections with SCBV and other sugarcane viruses.The proportion of mixed infections among the SCBV-positive samples was as high as 56.56%.Among the various types of mixed infections,two-virus and three-virus mixed infections were the most prevalent.[Conclusions]SCBV has emerged as a significant threat to the secure production of sugarcane in the Hainan sugarcane-growing region.It presents an explosive infection in the Hainan sugarcane-growing region and frequently combines with other sugarcane viruses to infect sugarcane.The findings of this study will provide a theoretical foundation for the prevention and control of sugarcane bacilliform virus disease.
基金supported by grants from the National Natural Science Foundation of China(32460505)China Agriculture Research System(CARS-11)+2 种基金the Chinese Academy of Tropical Agricultural Sciences for the Science and Technology Innovation Team of the National Tropical Agricultural Science Center(CATASCXTD202301)Additional support was provided by the Hainan Province Graduate Innovation Research Project(Hyb2020-09)the Key Laboratory of Tropical Fruits and Vegetables Quality and Safety for State Market Regulation(KF-2023016).
文摘The high content of cyanogenic glycosides(CG)in cassava tubers affects food safety.CG are involved in the plant growth and development and protect cassava leaves from herbivorous predators.However,the regulatory mechanism of CG biosynthesis remains poorly understood.Here,yeast one-hybrid assays were performed using a mixed cDNA library of cassava tubers and leaves as prey and the promoter of MeCYP79D2 as bait.MeCYP79D2,a cytochrome P450 protein,is the rate-limiting enzyme for CG synthesis in cassava.From this information,a candidate regulator of MeCYP79D2 was selected and identified as transcription factor MePHD1.2.MePHD1.2,located in the nucleus and exhibiting an inhibitory transcription activity directly bound to an AT-rich motif in the promoter of MeCYP79D2.In cassava,the transcriptional activity of MeCYP79D2 was considerably enhanced in mephd1.2 mutant lines leading to increased linamarin and lotaustralin contents.Deletion of MePHD1.2 promoted the production of CGs in cassava and decreased transcription inhibition on MeCYP79D2,exposing a novel regulatory module governing biosynthesis of CGs.
基金supported by grants from the National Key R&D Program of China(Grant No.2019YFD1000900)the Hainan Province Science and Technology Special Fund(Grant No.ZDYF2022XDNY253)the earmarked fund for CARS(Grant No.CARS-32-01)。
文摘Litchi(Litchi chinensis Sonn.)is a type of commercially prevalent subtropical and tropical fruit.Since litchi has a highly heterozygous genetic background and a long reproductive cycle,conventional breeding methods(such as hybridization)have limited ability to nurture new litchi cultivars.Here,an efficient and stable Agrobacterium tumefaciens-mediated genetic transformation of embryogenic callus was established in‘Feizixiao’litchi.Transgenic materials were verified using polymerase chain reaction(PCR)analysis,β-glucuronidase(GUS)assay,and green fluorescent protein(GFP)assay.To implement the technology of the Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)/associated protein 9(CRISPR/Cas9)technology in‘Feizixiao’litchi and verify the validity of these transformation systems,the litchi polyphenol oxidase gene(LcPPO,JF926153)was knocked out.Various categories of mutations,covering base insertions,deletions,and substitutions,were found in transgenic materials via sequence analysis.The transformation system achieved high feasibility and efficiency,and the system of CRISPR/Cas9 was successfully employed to edit genes in‘Feizixiao’litchi.This work provides an essential foundation for investigating the functions of genes and accelerating litchi genetic improvement.
基金supported by the National Natural Science Foundation of China (32260737)the Project of Sanya Yazhou Bay Science and Technology City, China (SCKJJYRC-2022-84 and SCKJ-JYRC-2022-93)the Hainan Provincial Natural Science Foundation of China (320QN305, 321MS091 and 320RC686)。
文摘Passion fruit(Passiflora edulis Sims) is a vine of the Passiflora genus in the Passifloraceae family. The extracted components include flavonoids and terpenoids, which have good anti-anxiety and anti-inflammatory effects in humans.In this study, we analyzed the transcriptomes of four tissues of the ‘Zixiang’ cultivar using RNA-Seq, which provided a dataset for functional gene mining. The de novo assembly of these reads generated 96 883 unigenes, among which 61 022 unigenes were annotated(62.99% yield). In addition to its edible value, another important application of passion fruit is its medicinal value. The flavonoids and terpenoids are mainly derivatives of luteolin, apigenin, cycloartane triterpenoid saponins and other active substances in leaf extracts. A series of candidate unigenes in the transcriptome data that are potentially involved in the flavonoid and terpenoid synthesis pathways were screened using homologybased BLAST and phylogenetic analysis. The results showed that the biosynthesis of triterpenoids in passion fruit comes from the branches of the mevalonate(MVA) and 2-C-methyl-D-erythritol 4-phosphate/1-deoxy-D-xylulose 5-phosphate(MEP/DOXP) pathways, which is different from the MVA pathway that is used in other fruit trees. Most of the candidate genes were found to be highly expressed in the leaves and/or flowers. Quantitative real-time PCR(qRT-PCR) verification was carried out and confirmed the reliability of the RNA-Seq data. Further amplification and functional analysis of these putative unigenes will provide additional insight into the biosynthesis of flavonoids and terpenoids in passion fruit.
基金supported by the National Key Research and Development Program of China(2022YFD2301100 and 2019YFD1000503)the Natural Science Foundation of Fujian Province(2021J01137)+1 种基金the Special Fund for Science and Technology Innovation of Fujian Agriculture and Forestry University(CXZX2020081A)the China Agriculture Research System(CARS-17).
文摘WRKY transcription factors,transcriptional regulators unique to plants,play an important role in defense response to pathogen infection.However,the resistance mechanisms of WRKY genes in sugarcane remain unclear.In the present study,gene ontology(GO)enrichment analysis revealed that WRKY gene family in sugarcane was extensively involved in the response to biotic stress and in defense response.We identified gene ScWRKY4,a classⅡc member of the WRKY gene family,in sugarcane cultivar ROC22.This gene was induced by salicylic acid(SA)and methyl jasmonate(MeJA)stress.Interestingly,expression of ScWRKY4 was down-regulated in smut-resistant sugarcane cultivars but up-regulated in smutsusceptible sugarcane cultivars infected with Sporisorium scitamineum.Moreover,stable overexpression of the ScWRKY4 gene in Nicotiana benthamiana enhanced susceptibility to Fusarium solani var.coeruleum and caused down-regulated expression of immune marker-related genes.Transcriptome analysis indicated suppressed expression of most JAZ genes in the signal transduction pathway.ScWRKY4 interacted with ScJAZ13 to repress its expression.We thus hypothesized that the ScWRKY4 gene was involved in the regulatory network of plant disease resistance,most likely through the JA signaling pathway.The present study depicting the molecular involvement of ScWRKY4 in sugarcane disease resistance lays a foundation for future investigation.
基金supported by the China Agriculture Research System (CARS11-HNCX)the Major Science and Technology Plan of Hainan Province (ZDKJ2021012)+3 种基金the Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences (1630052022008)the National Key Research and Development Program of China (2018YFD1000501)the National Natural Science Foundation of China (31501378)the Hainan Yazhou Bay Seed Lab (B21HJ0303)。
文摘Drought stress impairs plant growth and other physiological functions. MeHDZ14, a homeodomainleucine zipper I transcription factor, is strongly induced by drought stress in various cassava cultivars.However, the role of MeHDZ14 in cassava growth regulation has remained unclear. Here we report that MeHDZ14 affected plant height, such that a dwarf phenotype and altered internode elongation were observed in transgenic cassava lines. MeHDZ14 was found to negatively regulate the biosynthesis of lignin. Its overexpression resulted in abaxially rolled leaves. The morphogenesis of leaf epidermal cells was inhibited by overexpression of MeHDZ14, with decreased auxin and gibberellin and increased cytokinin contents. MeHDZ14 was found to regulate many drought-responsive genes, including genes involved in cell wall synthesis and expansion. MeHDZ14 bound to the promoter of caffeic acid 3-Omethyltransferase 1(MeCOMT1), acting as a transcriptional repressor of genes involved in cell wall development. MeHDZ14 appears to act as a negative regulator of internode elongation and epidermal cell morphogenesis during cassava leaf development.
基金supported by the Hainan Provincial Natural Science Foundation of China (322RC798)the National Key Research and Development Program of China (2018YFD1000501)+1 种基金the Major Science and Technology Plan of Hainan Province (ZDKJ2021012)the China Agriculture Research System (CARS11-HNCX)。
文摘Chilling-induced accumulation of reactive oxygen species(ROS) is harmful to plants,which usually produce anthocyanins to scavenge ROS as protection from chilling stress.As a tropical crop,cassava is hypersensitive to chilling,but the biochemical basis of this hypersensitivity remains unclear.We previously generated Me MYB2-RNAi transgenic cassava with increased chilling tolerance.Here we report that Me MYB2-RNAi transgenic cassava accumulated less ROS but more cyanidin-3-O-glucoside than the wild type under early chilling stress.Under this stress,the anthocyanin biosynthesis pathway was more active in Me MYB2-RNAi lines than in the wild type,and several genes involved in the pathway,including Me TT8,were up-regulated by Me MYB2-RNAi in the transgenic cassava.Me MYB2 bound to the Me TT8 promoter and blocked its expression under both normal and chilling conditions,thereby inhibiting anthocyanin accumulation.Me TT8 was shown to bind to the promoter of Dihydroflavonol 4-reductase(Me DFR-2)and increased Me DFR-2 expression.Me MYB2 appears to act as an inhibitor of chilling-induced anthocyanin accumulation during the rapid response of cassava to chilling stress.
基金This study was funded by Shenzhen Science and Technology Program(Grant No.RCYX20210706092103024)the Key-Area Research and Development Program of Guangdong Province(2020B020220004).
文摘In plants,5mC DNA methylation is an important and conserved epistatic mark involving genomic stability,gene transcriptional regulation,developmental regulation,abiotic stress response,metabolite synthesis,etc.However,the roles of 5mC DNA methylation modification(5mC methylation)in tea plant growth and development(in pre-harvest processing)and flavor substance synthesis in pre-and post-harvest processing are unknown.We therefore conducted a comprehensive methylation analysis of four key pre-harvest tissues(root,leaf,flower,and fruit)and two processed leaves during oolong tea post-harvest processing.We found that differential 5mC methylation among four key tissues is closely related to tissue functional differentiation and that genes expressed tissue-specifically,responsible for tissue-specific functions,maintain relatively low 5mC methylation levels relative to non-tissue-specifically expressed genes.Importantly,hypomethylation modifications of CsAlaDC and TS/GS genes in roots provided the molecular basis for the dominant synthesis of theanine in roots.In addition,integration of 5mC DNA methylationomics,metabolomics,and transcriptomics of post-harvest leaves revealed that content changes in flavor metabolites during oolong tea processing were closely associated with transcription level changes in corresponding metabolite synthesis genes,and changes in transcript levels of these important synthesis genes were strictly regulated by 5mC methylation.We further report that some key genes during processing are regulated by 5mC methylation,which can effectively explain the content changes of important aroma metabolites,includingα-farnesene,nerolidol,lipids,and taste substances such as catechins.Our results not only highlight the key roles of 5mC methylation in important flavor substance synthesis in pre-and post-harvest processing,but also provide epimutation-related gene targets for future improvement of tea quality or breeding of whole-tissue high-theanine varieties.
基金This study was funded by Shenzhen Science and Technology Program(Grant No.RCYX20210706092103024)Key-Area Research and Development Program of Guangdong Province(2020B020220004).
文摘Dear Editor,Tea plant(Camellia sinensis(L.)O.Kuntze)is one of the world’s most important non-alcoholic beverages,with great economic,health,and cultural value.Recently,several genomes of C.sinensis var.assamica(CSA)(Yunkang 10),C.sinensis var.sinensis(CSS)(Shuchazao,Biyun,Longjing 43,Tieguanyin,Huangdan),and ancient tea plant(DASZ)have been deciphered[1-3].
基金supported by the National Key Research and Development Program of China(2022YFD2301100)National Natural Science Foundation of China(32272156)+3 种基金Natural Science Foundation of Fujian Province,China(2022J01160)Central Publicinterest Scientific Institution Basal Research Fund(1630052024003,1630052024020)Chinese Academy of Tropical Agricultural Sciences for Science and Technology Innovation Team of National Tropical Agricultural Science Center(CATASCXTD202402)China Agriculture Research System of MOF and MARA(CARS-17).
文摘Sugarcane is recognized as the fifth largest crop globally,supplying 80%of sugar and 40%of bioenergy production.However,sugarcane genetic research has significantly lagged behind other crops due to its complex genetic background,high ploidy(8-13×),aneuploidy,limited flowering,and a long growth cycle(more than one year).Cross breeding began in 1887 following the discovery that sugarcane seeds could germinate.Both self-and cross-pollination and selection were conducted by sugarcane breeders,but new cultivars were often eliminated due to disease susceptibility.Within the Saccharum genus,different species possess variable numbers of chromosomes.Wild sugarcane species intercrossed with each other,leading to development of the‘Nobilization’breeding strategy,which significantly improved yield,sucrose,fiber content,and disease resistance,and accelerated genetic improvement of cultivars.In recent years,scientific achievements have also been made in sugarcane genome sequencing,molecular marker development,genetic linkage map construction,localization of quantitative trait locus(QTL),and trait-associated gene identification.This review focuses on the progress in sugarcane genetic research,analyzes the technical difficulties faced,presents opportunities and challenges,and provides guidance and references for future sugarcane genetics research and cultivar breeding.Finally,it offers directions for future on sugarcane genetics.
文摘Addressing global challenges such as energy sustainability,food security,and environmental conservation requires innovative agricultural solutions.Modern sugarcane(Saccharum hybrid)is a crucial crop that contributes not only to the sugar industry but also to bioenergy systems.Beyond its traditional role,sugarcane supports global food security,environmental sustainability,and economic empowerment of farmers.Over 80%of the worldwide sugarcane production is dedicated to sugar,a dietary staple(OECD-FAO,2024).The remaining 19%aid biofuel production,with sugarcane accounting for 24%of the global ethanol feedstock by 2033.As a C4 plant,sugarcane efficiently captures atmospheric carbon and acts as an important carbon sink.Additionally,sugarcane cultivation can lower local temperatures by nearly 1°C compared to pastures/natural vegetation(Loarie et al.,2011).Economically,sugarcane is a high-value cash crop,generating$43 billion annually in Brazil alone(Voora et al.,2023).
基金supported by National Natural Science Foundation of China(32272677)National Key R&D Program of China(2019YFD1001104)+1 种基金Central Publicinterest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences(1630032024026,1630032024001,1630052023011)Hainan Provincial Natural Science Foundation of China(323QN279)。
文摘Pineapple is the third most crucial tropical fruit worldwide and available in five varieties.Genomes of different pineapple varieties have been released to date;however,none of them are complete,with all exhibiting substantial gaps and representing only two of the five pineapple varieties.This significantly hinders the advancement of pineapple breeding efforts.In this study,we sequenced the genomes of three varieties:a wild pineapple variety,a fiber pineapple variety,and a globally cultivated edible pineapple variety.We constructed the first gap-free reference genome(Ref)for pineapple.By consolidating multiple sources of evidence and manually revising each gene structure annotation,we identified 26,656 proteincoding genes.The BUSCO evaluation indicated a completeness of 99.2%,demonstrating the high quality of the gene structure annotations in this genome.Utilizing these resources,we identified 7,209 structural variations across the three varieties.Approximately 30.8%of pineapple genes were located within±5 kb of structural variations,including 30 genes associated with anthocyanin synthesis.Further analysis and functional experiments demonstrated that the high expression of AcMYB528 aligns with the accumulation of anthocyanins in the leaves,both of which may be affected by a 1.9-kb insertion fragment.In addition,we developed the Ananas Genome Database,which offers data browsing,retrieval,analysis,and download functions.The construction of this database addresses the lack of pineapple genome resource databases.In summary,we acquired a seamless pineapple reference genome with highquality gene structure annotations,providing a solid foundation for pineapple genomics and a valuable reference for pineapple breeding.
