Fig fruit firmness decreases rapidly during ripening and after harvest,resulting in poor storability and transportation loss,which severely restricts development of the fresh fig industry.APETALA2/ethylene-responsive ...Fig fruit firmness decreases rapidly during ripening and after harvest,resulting in poor storability and transportation loss,which severely restricts development of the fresh fig industry.APETALA2/ethylene-responsive factor(AP2/ERF)transcription factors are downstream components of the ethylene-signaling pathway that play crucial roles in quality formation during fruit ripening.In this study,Ficus carica(Fc)ERF12 was clustered in repressor subfamily VIII of ERFs through phylogenetic analysis,and further recruited by its two EAR motifs and expression pattern during fig ripening.DNA affinity purification sequencing analysis indicated that FcERF12 binds to the promoter or gene body regions of multiple ripening-related genes,including cell wall-modification genes FcPG,FcXTH and FcPME,and ethylene-biosynthesis genes FcACS and FcACO.Yeast two-hybrid assay demonstrated that FcERF12 interacts with TOPLESS(TPL)co-repressors FcTPL1,FcTPL4 and FcTPL5,and histone deacetylases FcHDA6 and FcHDA19;interaction with FcTPL4 and FcTPL5 relied on the C-terminal EAR motif.Overexpressing FcERF12 in tomato did not change fruit size or yield,but resulted in an 18.37%increment in fruit firmness and a 49.62%reduction in ethylene-release rate at fruit ripening,accompanied by a significant decrease in seed number per fruit.Transcriptomic analysis revealed downregulation of tomato cell wallmodification genes SlPL,SlEXP and SlPG,and ethylene-synthesis genes SlACO and SlACS.Metabolomic profiling identified 82 differentially accumulated flavonoid metabolites,61 of them showing significantly decreased contents.Taken together,our results exhibit the negative regulatory role of FcERF12 in fig ethylene-signal transduction,providing new information on precise control of fruit firmness and other quality traits at ripening.展开更多
Kiwifruit (Actinidia deliciosa (A. Chev.) C. F. Liang et A. R. Ferguson cv. Bruno) was used toinvestigate the effects of acetylsalicylic acid (ASA, 1.0 mmol/L, pH 3.5) and ethylene (100 mL/L) treat-ments on changes at...Kiwifruit (Actinidia deliciosa (A. Chev.) C. F. Liang et A. R. Ferguson cv. Bruno) was used toinvestigate the effects of acetylsalicylic acid (ASA, 1.0 mmol/L, pH 3.5) and ethylene (100 mL/L) treat-ments on changes at endogenous salicylic acid (SA) levels and other senescence-related factors duringfruit ripening and softening at 20 ℃. The level of endogenous SA in ripening fruits declined and a closerelationship was observed between the change at endogenous SA level and the rate of fruit ripening andsoftening. ASA treatment elevated SA level in the fruit, slowed down the increases in lipoxygenase (LOX)and allene oxide synthase (AOS) activities, decreased the O22-. production in the preclimacteric phase andthe early phase of ethylene climacteric rise, maintained the stability of cell membrane, inhibited ethylenebiosynthesis, postponed the onset of the ethylene climacteric, and delayed the process of fruit ripeningand softening. On the contrary, application of ethylene to ripening kiwifruit resulted at a lower SA level, anaccelerated increases in the activities of LOX and AOS and the rate of O22-. production, an elevated relativeelectric conductivity and an advanced onset of ethylene climacteric, and a quicker fruit ripening andsoftening. It is suggested that the effects of ASA on ripening kiwifruit can be attributed to its ability toscavenge O22-. and/or to maintain stability of cell membrane.展开更多
Autophagy is a universal cellular process in eukaryotes that plays a critical role in plant growth and stress response.However,the role of autophagy in fruit ripening is largely unknown.Here,we demonstrated that most ...Autophagy is a universal cellular process in eukaryotes that plays a critical role in plant growth and stress response.However,the role of autophagy in fruit ripening is largely unknown.Here,we demonstrated that most autophagy-related genes(ATGs)were up-regulated during tomato(Solanum lycopersicum L.)fruit ripening.By using mutants of different autophagy pathway genes(ATG6,ATG10,ATG18a),we revealed that the deficiency of autophagy delayed the ripening of fruit.Compared with wild-type(WT),the production of ethylene was significantly reduced and the accumulation of lycopene was delayed in atg mutants during fruit ripening.We also observed the contents of glucose and fructose were both significantly decreased in atg mutants compared with WT,while the content of organic acids showed the opposite trend.Additionally,the negative regulator of ethylene production,APETALA2a(AP2a),interacted with ATG8 through a specific ATG8-interacting motif(AIM)and could be degraded through the autophagy pathway.These results demonstrate that autophagy plays a critical role in fruit ripening by regulating ethylene production and the accumulation of pigments,sugars and organic acids in tomato.展开更多
Melon(Cucumis melo)is an economically important horticultural crop cultivated worldwide.NAC(NAM/ATAC/CUC)transcription factors play crucial roles in the transcriptional regulation of various developmental stages in pl...Melon(Cucumis melo)is an economically important horticultural crop cultivated worldwide.NAC(NAM/ATAC/CUC)transcription factors play crucial roles in the transcriptional regulation of various developmental stages in plant growth and fruit development,but their gene functions in melon remain largely unknown.Here,we identified 78 CmNAC family genes with an integrated and conserved no apical meristem(NAM)domain in the melon genome by performing genome-wide identification and bioinformatics analysis.Transcriptome data analysis and qRTPCR results showed that most CmNACs are specifically enriched in either the vegetative or reproductive organs of melon.Through genetic transformation,we found that overexpression of CmNAC34 in melons led to early ripening fruits,suggesting its positive role in promoting fruit maturation.Using yeast two-hybrid and bimolecular fluorescence complementation assays,we verified the direct protein interaction between CmNAC34 and CmNACNOR.The expression patterns of CmNAC34 and CmNAC-NOR were similar in melon tissues,and subcellular localization revealed their nuclear protein characteristics.We transformed CmNAC-NOR in melon and found that its overexpression resulted in early ripening fruits.Then,the yeast one-hybrid and dual luciferase reporter gene assays showed that the CmNAC34 protein can bind to the promoters of two glyoxalase(GLY)genes,which are involved in the abscisic acid signal pathway and associated with fruit regulation.These findings revealed the molecular characteristics,expression profiles,and functional patterns of the NAC family genes and provide new insights into the molecular mechanism by which CmNAC34 regulates climacteric fruit ripening.展开更多
Brassinosteroids（BRs）, a class of steroidal phytohormones are essential for many biological processes in plant. However, little is known about their roles in fruit development. Tomato is a highly valuable vegetable ...Brassinosteroids（BRs）, a class of steroidal phytohormones are essential for many biological processes in plant. However, little is known about their roles in fruit development. Tomato is a highly valuable vegetable and has been adopted as the model species for studying fruit growth, development, and ripening. To understand the role of endogenous BRs in the development of tomato fruit, the expression patterns of three homologues of DWF4 gene were investigated and the transgenic tomato plants were generated in which the Gh DWF4 gene from upland cotton（Gossypium hirsutum L.） was ectopically expressed. The contents of main quality components were analyzed in fruits of transgenic tomato line and non-transgenic line（control plant, CP） when the fruit was mature. Sl CYP90B3 that possesses high homology with Gh DWF4 preferentially expressed in mature fruit. Significantly higher contents of soluble sugar, soluble proteins, and vitamin C were obtained in fruit of transgenic tomato lines compared with those in the CP. Furthermore, overexpressing Gh DWF4 promoted fruit growth and ripening. The weight per fruit was increased by about 23% in transgenic lines. In addition, overexpressing Gh DWF4 promoted the germination of transgenic tomato seeds and hypocotyl elongation of seedlings. These results indicated that overexpressing Gh DWF4 gene in tomato could increase the contents of many nutrients in fruit and accelerate fruit ripening. It is suggested that increased endogenous BRs in fruit affect the growth and development of tomato fruit and therefore improved the nutrient quality of tomato.展开更多
A 1 250 bp cDNA fragment encoding β-mannanase, named MaMAN, was cloned from banana （Musa spp cv. Baxi） fruit using degenerate primers designed with reference to the conserved nucleic acid sequences of known β-mann...A 1 250 bp cDNA fragment encoding β-mannanase, named MaMAN, was cloned from banana （Musa spp cv. Baxi） fruit using degenerate primers designed with reference to the conserved nucleic acid sequences of known β-mannanase genes by RT-PCR. Sequence analysis showed that MaMAN cDNA encompassed a 1 085 bp open-reading frame （ORF）, encoding a predicted polypeptide of 395 amino acids. Alignment of the deduced amino acid sequence of MaMAN and other putative β-mannanases showed that MaMAN has an identity of 86, 70, 69, 54, and 57%, respectively, to β-mannanases from tomato, lettuce, arabidopsis, carrot and oryza sativa. The catalytic residues： Asn203, Glu204, Glu318 and the active site residues： Arg86, His277, Tyr279, and Trp360, which were strictly conserved in the glycoside hydrolase family 5 to which all β-mannanases belonged, were found in MaMAN. Semi-quantitative RT-PCR revealed that the level of MaMAN transcript in the pulp increased during banana fruit ripening, suggesting that MaMAN was likely to be involved highly in banana fruit softening.展开更多
The regulation of apple(Malus domestica)fruit texture during ripening is complex and a fundamental determinant of its commercial quality.In climacteric fruit,ripening-related processes are regulated by ethylene(ET),an...The regulation of apple(Malus domestica)fruit texture during ripening is complex and a fundamental determinant of its commercial quality.In climacteric fruit,ripening-related processes are regulated by ethylene(ET),and jasmonate(JA)is also involved in the ethylene biosynthesis pathway,mainly through the transcription factor MYC2.However,the molecular genetic mechanism for fruit ripening processes between the JA and ET signaling pathways still needs to be elucidated.In order to explore how JA regulates apple fruit ripening through ERF4,we used’Gala’and’Ralls Janet’fruit at different developmental stages as experimental materials to determine the fruit firmness and related gene expression analysis.Meanwhile,we carried out different hormone treatments on’Gala’fruit at ripening stage.Here,we show that ERF4 is a core JA signaling hub protein JASMONATE ZIM-DOMAIN(JAZ)interactor that affects ethylene signaling pathways.During fruit development,ERF4 represses the expression of ACS1 and ACO1 by interacting with JAZ,as well as with the JA-activated transcription factor MYC2.Ripening is promoted in JAZ-suppressed apples.Thus,ERF4 acts as a molecular link between ethylene and JA hormone signals,and the natural variation of the ERF4Ethylene-responsive binding factor-associated amphiphilic repression(EAR)motif decreases repression of ethylene biosynthesis genes.展开更多
Tomato is one of the most important vegetable crops in the world and is a model plant used to study the ripening of climacteric fleshy fruit.During the ripening process of tomato fruit,flavor and aroma metabolites,col...Tomato is one of the most important vegetable crops in the world and is a model plant used to study the ripening of climacteric fleshy fruit.During the ripening process of tomato fruit,flavor and aroma metabolites,color,texture and plant hormones undergo significant changes.However,low temperatures delayed the ripening process of tomato fruit,inhibiting flavor compounds and ethylene production.Metabolomics and transcriptomics analyses of tomato fruit stored under low temperature(LT,5°C)and room temperature(RT,25°C)were carried out to investigate the effects of storage temperature on the physiological changes in tomato fruit after harvest.The results of transcriptomics changes revealed that the differentially expressed genes(DEGs)involved in tomato fruit ripening,including several kinds of transcription factors(TFs)(TCP,WRKY,MYB and bZIP),enzymes involved in cell wall metabolism[beta-galactosidase(β-GAL),pectinesterase(PE)and pectate lyase(PL),cellulose and cellulose synthase(CESA)],enzymes associated with fruit flavor and aroma[acetyltransferase(AT),malic enzyme(ME),lipoxygenase(LOX),aldehyde dehydrogenase(ALDH),alcohol dehydrogenase(ADH)and hexokinase(HK)],genes associated with heat stress protein 70 and genes involved in the production of plant hormones such as Ethylene responsive factor 1(ERF1),Auxin/indoleacetic acids protein(AUX/IAA),gibberellin regulated protein.Based on the above results,we constructed a regulatory network model of the effects of different temperatures during the fruit ripening process.According to the analysis of the metabolomics results,it was found that the contents of many metabolites in tomato fruit were greatly affected by storage temperature,including,organic acids(L-tartaric acid,a-hydroxyisobutyric acid and 4-acetamidobutyric acid),sugars(melezitose,beta-Dlactose,D-sedoheptulose 7-phosphate,2-deoxyribose 1-phosphate and raffinose)and phenols(coniferin,curcumin and feruloylputrescine).This study revealed the effects of storage temperature on postharvest tomato fruit and provided a basis for further understanding of the molecular biology and biochemistry of fruit ripening.展开更多
Fruit softening in tomato(Solanum lycopersicum)is closely associated with cell wall disassembly,which is brought about through the action of a range of cell wall structure-related enzymes and other proteins such as ex...Fruit softening in tomato(Solanum lycopersicum)is closely associated with cell wall disassembly,which is brought about through the action of a range of cell wall structure-related enzymes and other proteins such as expansins.Xyloglucan endotransglucosylase/hydrolase(XTH)(EC 2.4.1.207 and/or EC 3.2.1.151)has been proposed to be key player involved in xyloglucan metabolism.SlXTH5 showed the highest expression level among all SlXTHs during tomato ripening.In this study,the role of SlXTH5 involved in tomato softening was investigated in CRISPR-based knockout mutants of SlXTH5.Loss-of-function of SlXTH5 in transgenic tomato lines resulted in slightly firmer fruit pericarp,but significantly decreased their color index compared with azygous wild type(WT)control fruits.Increased paste viscosity was detected in CRISPR mutants,indicating that the activity of SlXTH5 is responsible for maintaining cell wall structural integrity.Immunocytochemistry studies were performed using the monoclonal antibody probe LM25 to examine the localization and distribution of xyloglucan in the pericarp cells of the CRISPR mutant fruits.The data indicated more xyloglucan was retained in the pericarp of CRISPR mutant fruit than in WT control fruit.This study revealed the link between SlXTH5 and xyloglucan metabolism and indicated the potential of manipulating SlXTH5 to regulate fruit softening.展开更多
Fruit development and ripening is a complex procedure(Malus×domestica Borkh.)and can be caused by various factors such as cell structure,cell wall components,and cell wall hydrolytic enzymes.In our study,we focus...Fruit development and ripening is a complex procedure(Malus×domestica Borkh.)and can be caused by various factors such as cell structure,cell wall components,and cell wall hydrolytic enzymes.In our study,we focused on the variations in fruit firmness,cell wall morphology and components,the activity of cell wall hydrolytic enzymes and the expression patterns of associated genes during fruit development in two different types of apple cultivars,the hard-crisp cultivar and the loose-crisp cultivar.In this paper,the aim was to find out the causes of the texture variations between the different type cultivars.Cell wall materials(CWMs),hemicellulose and cellulose content were strongly associated with variations in fruit firmness during the fruit development.The content of water soluble pectin(WSP)and chelator soluble pectin(CSP)gradually increased,while the content of ionic soluble pectin(ISP)showed inconsistent trends in the four cultivars.The activities of polygalacturonase(PG),β-galactosidase(β-gal),cellulase(CEL),and pectate lyase(PL)gradually increased in four cultivars.And the activities of PG,β-gal,and CEL were higher in‘Fuji’and‘Honeycrisp’fruit with the fruit development,while the activity of PL of‘Fuji’and‘Honeycrisp’was lower than that of‘ENVY’and‘Modi’.Both four cultivars of fruit cells progressively became bigger as the fruit expanded,with looser cell arrangements and larger cell gaps.According to the qRT-PCR,the relative expression levels of MdACO and Mdβ-gal were notably enhanced.Our study showed that there were large differences in the content of ISP and hemicellulose,the activity of PL and the relative expression of Mdβ-gal between two different types of apple cultivars,and these differences might be responsible for the variations in the texture of the four cultivars.展开更多
Fruit ripening has been reported to be related to calcium(Ca),but the underlying mechanisms by which Ca regulates this process remain largely unknown.In order to study the changes of proteins and enriched phosphopepti...Fruit ripening has been reported to be related to calcium(Ca),but the underlying mechanisms by which Ca regulates this process remain largely unknown.In order to study the changes of proteins and enriched phosphopeptides,we conducted TMT labeling,bio-material-based PTM enrichment based on mass spectrometry in Ca-treated‘Golden Delicious’(GD)apple fruit(Malus×domestica).This dataset presents a comprehensive overview of the critical pathways involved in fruit ripening.A total of 47 proteins and 124 phosphoproteins significantly changed in Ca-treated fruit,which are crucial for regulating the cell wall and cytoskeleton,Ca-mediated signaling and transport,ethylene production,protein fate,especially ubiquitination-based protein degradation,and primary and secondary metabolisms.Our results indicated that Ca inhibited the abundance of polygalacturonase(PG)activity and increased the phosphorylation level of CSLD3.PG and phosphorylation were involved in cell wall degradation,thereby delaying fruit softening.As a secondary messenger,Ca-mediated signaling subsequently triggered downstream mitogen-activated protein kinases(MAPK)cascades and activated the membrane,transport,and ROS signaling.Moreover,MdEIN2,a key enzyme involved in the ubiquitin of protein modification,increased at Ser753 and Ser758 in Ca-treated fruit.Furthermore,diverse primary and secondary metabolisms including glycolysis,fatty acid metabolism,and oxidation respiratory chain were modulated to prevent fruit softening.These results provide basic information from protein and phosphorylation levels for apple fruit ripening during storage,which may be helpful for apple fruit storage control.展开更多
Abscisic acid(ABA)is a major regulator of non-climacteric fruit ripening;however,the role of ABA in the ripening of climacteric fruit is not clear.Here,as a typical climacteric fruit,apricots were used to investigate ...Abscisic acid(ABA)is a major regulator of non-climacteric fruit ripening;however,the role of ABA in the ripening of climacteric fruit is not clear.Here,as a typical climacteric fruit,apricots were used to investigate the role of ABA in fruit ripening.Based on weighted gene coexpression network analysis(WGCNA)of our previous transcriptome data,we treated‘Danxing’fruit with exogenous ABA and obtained ABA receptor genes,genes related to ABA biosynthesis and signal transduction,and analyzed the response of these candidate genes to exogenous ABA during fruit ripening.Subsequently,the full length of candidate PYLs genes were cloned,and their putative function were analyzed by phylogenetic analysis and protein structure domain analysis.And then the function of one candidate gene PaPYL9 was verified by using transgenic tomato.Furthermore,the response genes in transgenic tomato were screened by transcriptome sequencing,and ultimately the related regulatory network was proposed.The results showed that the injection of exogenous 1.89 mmol·L^(-1) ABA remarkably promoted fruit coloration,and increased the color index for red grapes(CIRG)and the total soluble solids(TSS)content,but significantly decreased the firmness and titratable acid(TA)content(p<0.01).Nordihydroguaiaretic acid(NDGA),the inhibitor of ABA,appeared to have the converse role in TA,TSS,CIRG and firmness,during the ripening process.One NCED(9-cis-epoxycarotenoiddioxygenase)and five ABA receptor genes related to signal transduction were mined from the transcriptome data of apricot fruit through WGCNA.Compared with the control,the expression levels of NCED1,PYL9(PYR/PYL/RCAR),SnRK2(SUCROSE NON-FERMENTING1(SNF1)-RELATED PROTEIN KINASE 2S),and ABF2(ABRE-binding bZIP transcription)were induced dramatically by ABA treatment(p<0.01),while NDGA treatment significantly inhibited their expression.Based on gene expression and protein domain analysis,we inferred that PaPYL9 is putatively involved in apricot fruit ripening.Overexpression of PaPYL9 in Micro-TOM tomatoes resulted in the promotion of early ripening.Simultaneously,the expression levels of genes related ethylene biosynthesis,chlorophyll degradation,fruit softening,flavor formation,pigment synthesis,and metabolism were all significantly induced in overexpression of PaPYL9 tomatoes.This indicates the central role of ABA in climacteric fruit ripening.A regulatory network was tentatively proposed,laying the foundation to unveil the molecular mechanism of the regulatory role of PaPYL9 in fruit ripening.展开更多
Salicylic acid(SA) plays a pivotal role in delaying fruit ripening and senescence. However, little is known about its underlying mechanism of action. In this study, RNA sequencing was conducted to analyze and compare ...Salicylic acid(SA) plays a pivotal role in delaying fruit ripening and senescence. However, little is known about its underlying mechanism of action. In this study, RNA sequencing was conducted to analyze and compare the transcriptome profiles of SA-treated and control pear fruits. We found a total of 159 and 419 genes differentially expressed between the SA-treated and control pear fruits after 12 and 24 h of treatment, respectively. Among these differentially expressed genes(DEGs), 125 genes were continuously differentially expressed at both treatment times, and they were identified as candidate genes that might be associated with SA-regulated fruit ripening and senescence. Bioinformatics analysis results showed that 125 DEGs were mainly associated with plant hormone biosynthesis and metabolism, cell wall metabolism and modification, antioxidant systems, and senescence-associated transcription factors. Additionally, the expression of several candidate DEGs in ripening and senescent pear fruits after SA treatments were further validated by quantitative real-time PCR(qRT-PCR). This study provides valuable information and enhances the understanding of the comprehensive mechanisms of SA-meditated pear fruit ripening and senescence.展开更多
The characteristics of fruit ripening and expression of ripening-related genes were investigated in epi, an ethylene overproduction mutant of tomato (Lycopersicon esculentum Mill.). The epi produces apparently more et...The characteristics of fruit ripening and expression of ripening-related genes were investigated in epi, an ethylene overproduction mutant of tomato (Lycopersicon esculentum Mill.). The epi produces apparently more ethylene than its wild type VFN8 at every stage of vegetative and fruit growth and ripening; compared to VFN8, the epi fruit showed higher CO2 evolution, faster descending of chlorophyll, slightly quicker increase of carotenoid and lycopene, and faster reduction in pericarp firmness during maturation and ripening; and the mRNAs of three ripening-related genes including E8, pTOM5 and pTOM6 were at higher levels in epi. The ripening-related characteristics changing of the fruit are consistent with the increase of ethylene production and ripening-related genes expression. These results suggest that epi mutation possibly did not affect the ethylene perception and signaling during fruit ripening, and that the modified characteristics of fruit ripening possibly resulted from the ethylene over- production and increased expression of ripening-related genes.展开更多
The purpose of this study is to explore the influence of co-suppressing tomato ACC oxidase Ⅰ on the expression of fruit ripening-related and pathogenesis-related protein genes, and on the biosynthesis of endogenous e...The purpose of this study is to explore the influence of co-suppressing tomato ACC oxidase Ⅰ on the expression of fruit ripening-related and pathogenesis-related protein genes, and on the biosynthesis of endogenous ethylene and storage ability of fruits. Specific fragments of several fruit ripening-related and pathogenesis-related protein genes from tomato （Lycopersicon esculentum） were cloned, such as the l-aminocyclopropane-1-carboxylic acid oxidase 1 gene （LeAC01）, 1- aminocyclopropane-l-carboxylic acid oxidase 3 gene （LeAC03）, EIN3-binding F-box 1 gene （LeEBF1）, pathogenesis-related protein 1 gene （LePR1）, pathogenesis-related protein 5 gene （LePR5）, and pathogenesis-related protein osmotin precursor gene （LeNP24） by PCR or RT-PCR. Then these specific DNA fragments were used as probes to hybridize with the total RNAs extracted from the wild type tomato Ailsa Craig （AC＋＋） and the LeAC01 co-suppression tomatoes （V1187 and T4B）, respectively. At the same time, ethylene production measurement and storage experiment of tomato fruits were carded out. The hybridization results indicated that the expression of fruit ripening-related genes such as LeACO3 and LeEBF1, and pathogenesis-related protein genes such as LePR1, LePR5, and LeNP24, were reduced sharply, and the ethylene production in the fruits, wounded leaves decreased and the storage time of ripening fruits was prolonged, when the expression of LeACO1 gene in the transgenic tomato was suppressed. In the co-suppression tomatoes, the expression of fruit ripening-related and pathogenesis-related protein genes were restrained at different degrees, the biosynthesis of endogenous ethylene decreased and the storage ability of tomato fruits increased.展开更多
Activities of NAD kinase(NADK)and NADP phosphatase and relationship between the two enzymes and temperature, respiration, ethylene production and trifluoperazine(TFP) were studied during ripening and senescence of str...Activities of NAD kinase(NADK)and NADP phosphatase and relationship between the two enzymes and temperature, respiration, ethylene production and trifluoperazine(TFP) were studied during ripening and senescence of strawberry and tomato fruits after harvest at 4℃ and 20℃. The activity of NAD kinase in strawberry decreased slowly during first four days, then increased gradually. The NADP phosphatase activity increased at the second day, decreased the next day,then increased again. In tomato fruit, the activities of NAD kinase and NADP phosphatase increased at the second day, decreased with the ripening and senescence of the fruit. The change trend of NAD kinase and respiration in the two fruits were similar, the same were NADP phosphatase and ethylene production. TFP enhanced the activity of NAD kinase and had little effect on NADP phosphatase. Low temperature(4℃) activated the NAD kinase and reduced the activity of NADP phosphatase. These results indicated that the NAD kinase and NADP phosphatase were related to the ripening and senescence of strawberry and tomato fruits. The activation of NAD kinase probably postponed the ripening and senescence of the fruits.展开更多
The fruits of peach cultivar Yuhua 3 were used as materials to investigate the changes of active oxygen and related enzymes in mitochondria respiratory metabolism during ripening of peach fruit,involving their influen...The fruits of peach cultivar Yuhua 3 were used as materials to investigate the changes of active oxygen and related enzymes in mitochondria respiratory metabolism during ripening of peach fruit,involving their influence on the proceeding of peach fruit senescence.The results showed that the large decrease in firmness occurred between maturity II and IV.The decrease in firmness coincided with an increase in respiratory intensity.Obvious peaks of respiratory intensity lagging to the rapid change of fruit firmness could be shown during peach ripening.Reactive oxygen species(ROS)had a cumulative process and positively correlated with respiratory intensity.During peach ripening,the content of Ca^2+increased,the activities of succinic dehydrogenase(SDH),cytochrome C oxidase(CCO),H+-ATPase,and Ca^2+-ATPase decreased varying in different degree at the later step of ripening.These suggested a close relationship existed between ROS metabolism and mitochondrial respiration,namely,both ROS metabolism and mitochondrial respiration probably played important roles in ripening and senescing of peach fruit.展开更多
Fruit ripening is a complex process and is regulated by many factors. Ethylene and polygalacturonase （PG）, lipoxygenase （LOX）, expansin （EXP） are all critical regulating factors in fruit ripening and softening p...Fruit ripening is a complex process and is regulated by many factors. Ethylene and polygalacturonase （PG）, lipoxygenase （LOX）, expansin （EXP） are all critical regulating factors in fruit ripening and softening process. With antisense ACS tomato, Nr mutant tomato and cultivated tomato as materials, Northern blot hybridization showed that PG, LeEXP1 and LOXexpressed differently in different parts of cultivated tomato fruit during ripening, which was related to fruit ripening. The ripening process of columella and radial pericarp was faster than pericarp. In both Nr mutant and antisense ACS transgenic tomato fruit, expression levels ofPG, LeEXPI and LOXwere generally lower than those in cultivated fruit but still related to fruit ripening. The expression levels ofPG, LeEXP1 and LOX increased in the mature green tomato fruits after 0.5 h treatment with ethylene （100 μL/L）. These results indicate that gene expression ofPG, LeEXP1 and LOXwere positively regulated by ethylene. The time and cumulative effect of the concentration exists in the expression of PG regulated by ethylene. The regulation of LOX expression mainly depended on the fruit development after great amount of ethylene was produced. PG played a major role in ripening and softening of tomato fruit, and cooperated with the regulation of EXP and LOX.展开更多
Fruit ripening is a programmed process involving dramatic physiological changes.It is regulated by various phytohormones such as ethylene and abscisic acid(ABA),which activate ripening-related gene expression and affe...Fruit ripening is a programmed process involving dramatic physiological changes.It is regulated by various phytohormones such as ethylene and abscisic acid(ABA),which activate ripening-related gene expression and affect respiration,metabolism,and cell homeostasis(Liu et al.,2015).Autophagy is a key cellular recycling mechanism that is induced during cellular reprogramming(Sun et al.,2021),and its activity is also upregulated during fruit ripening in many species.However,a few independent studies have come up with different conclusions,adding complexity to the understanding of the contribution of autophagy to fruit ripening.Here,we focus on recent discoveries and discuss possible roles of autophagy in fruit ripening.展开更多
Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperat...Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperated with MaHDA1 to precisely regulate the transcription of ripening-associated genes via histone deacetylation.However,whether MaERF11 is subjected to post-translational modification during banana ripening is largely unknown.In this study,we found that MaERF11 targeted a subset of starch degradation-related genes using the DNA affinity purification sequence(DAP-Seq)approach.Electrophoretic mobility shift assay(EMSA)and dual-luciferase reporter assay(DLR)demonstrated that MaERF11 could specifically bind and repress the expression of the starch degradation-related genes MaAMY3,MaBAM2 and MaGWD1.Further analyses of yeast two-hybrid(Y2H),bimolecular fluorescence complementation(BiFC)and Luciferase complementation imaging(LCI)assays indicated that MaERF11 interacted with the ubiquitin E3 ligase MaRFA1,and this interaction weakened the MaERF11-mediated transcriptional repression capacity.Collectively,our results suggest an additional regulatory layer in which MaERF11 regulates banana fruit ripening and expands the regulatory network in fruit ripening at the post-translational modification level.展开更多
基金supported by the key research project for fig development of Weiyuan County(Grant No.1002-69199007),China.
文摘Fig fruit firmness decreases rapidly during ripening and after harvest,resulting in poor storability and transportation loss,which severely restricts development of the fresh fig industry.APETALA2/ethylene-responsive factor(AP2/ERF)transcription factors are downstream components of the ethylene-signaling pathway that play crucial roles in quality formation during fruit ripening.In this study,Ficus carica(Fc)ERF12 was clustered in repressor subfamily VIII of ERFs through phylogenetic analysis,and further recruited by its two EAR motifs and expression pattern during fig ripening.DNA affinity purification sequencing analysis indicated that FcERF12 binds to the promoter or gene body regions of multiple ripening-related genes,including cell wall-modification genes FcPG,FcXTH and FcPME,and ethylene-biosynthesis genes FcACS and FcACO.Yeast two-hybrid assay demonstrated that FcERF12 interacts with TOPLESS(TPL)co-repressors FcTPL1,FcTPL4 and FcTPL5,and histone deacetylases FcHDA6 and FcHDA19;interaction with FcTPL4 and FcTPL5 relied on the C-terminal EAR motif.Overexpressing FcERF12 in tomato did not change fruit size or yield,but resulted in an 18.37%increment in fruit firmness and a 49.62%reduction in ethylene-release rate at fruit ripening,accompanied by a significant decrease in seed number per fruit.Transcriptomic analysis revealed downregulation of tomato cell wallmodification genes SlPL,SlEXP and SlPG,and ethylene-synthesis genes SlACO and SlACS.Metabolomic profiling identified 82 differentially accumulated flavonoid metabolites,61 of them showing significantly decreased contents.Taken together,our results exhibit the negative regulatory role of FcERF12 in fig ethylene-signal transduction,providing new information on precise control of fruit firmness and other quality traits at ripening.
文摘Kiwifruit (Actinidia deliciosa (A. Chev.) C. F. Liang et A. R. Ferguson cv. Bruno) was used toinvestigate the effects of acetylsalicylic acid (ASA, 1.0 mmol/L, pH 3.5) and ethylene (100 mL/L) treat-ments on changes at endogenous salicylic acid (SA) levels and other senescence-related factors duringfruit ripening and softening at 20 ℃. The level of endogenous SA in ripening fruits declined and a closerelationship was observed between the change at endogenous SA level and the rate of fruit ripening andsoftening. ASA treatment elevated SA level in the fruit, slowed down the increases in lipoxygenase (LOX)and allene oxide synthase (AOS) activities, decreased the O22-. production in the preclimacteric phase andthe early phase of ethylene climacteric rise, maintained the stability of cell membrane, inhibited ethylenebiosynthesis, postponed the onset of the ethylene climacteric, and delayed the process of fruit ripeningand softening. On the contrary, application of ethylene to ripening kiwifruit resulted at a lower SA level, anaccelerated increases in the activities of LOX and AOS and the rate of O22-. production, an elevated relativeelectric conductivity and an advanced onset of ethylene climacteric, and a quicker fruit ripening andsoftening. It is suggested that the effects of ASA on ripening kiwifruit can be attributed to its ability toscavenge O22-. and/or to maintain stability of cell membrane.
基金supported by the National Natural Science Foundation of China(Grant Nos.32302642,32272790)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(Grant No.SN-ZJU-SIAS-0011)+1 种基金Collaborative Promotion Program of Zhejiang Provincial Agricultural Technology of China(Grant No.2023ZDXT05)the Fundamental Research Funds for the Central Universities(Grant No.226-2022-00122).
文摘Autophagy is a universal cellular process in eukaryotes that plays a critical role in plant growth and stress response.However,the role of autophagy in fruit ripening is largely unknown.Here,we demonstrated that most autophagy-related genes(ATGs)were up-regulated during tomato(Solanum lycopersicum L.)fruit ripening.By using mutants of different autophagy pathway genes(ATG6,ATG10,ATG18a),we revealed that the deficiency of autophagy delayed the ripening of fruit.Compared with wild-type(WT),the production of ethylene was significantly reduced and the accumulation of lycopene was delayed in atg mutants during fruit ripening.We also observed the contents of glucose and fructose were both significantly decreased in atg mutants compared with WT,while the content of organic acids showed the opposite trend.Additionally,the negative regulator of ethylene production,APETALA2a(AP2a),interacted with ATG8 through a specific ATG8-interacting motif(AIM)and could be degraded through the autophagy pathway.These results demonstrate that autophagy plays a critical role in fruit ripening by regulating ethylene production and the accumulation of pigments,sugars and organic acids in tomato.
基金funded by the National Natural Science Foundation of China(32202513)the Applied Technology Research and Development Foundation of Inner Mongolia Autonomous Region,China(2021PT0001)+3 种基金the Natural Science Foundation of Inner Mongolia Autonomous Region,China(2021BS03002)the Inner Mongolia Autonomous Region Universities“Young Science and Technology Talent Support Project”,China(NJYT24067)the Inner Mongolia University High-Level Talent Research Program,China(10000-21311201/056)the Inner Mongolia Autonomous Region Department of Education First-class Scientific Research Project,China(YLXKZX-ND-030)。
文摘Melon(Cucumis melo)is an economically important horticultural crop cultivated worldwide.NAC(NAM/ATAC/CUC)transcription factors play crucial roles in the transcriptional regulation of various developmental stages in plant growth and fruit development,but their gene functions in melon remain largely unknown.Here,we identified 78 CmNAC family genes with an integrated and conserved no apical meristem(NAM)domain in the melon genome by performing genome-wide identification and bioinformatics analysis.Transcriptome data analysis and qRTPCR results showed that most CmNACs are specifically enriched in either the vegetative or reproductive organs of melon.Through genetic transformation,we found that overexpression of CmNAC34 in melons led to early ripening fruits,suggesting its positive role in promoting fruit maturation.Using yeast two-hybrid and bimolecular fluorescence complementation assays,we verified the direct protein interaction between CmNAC34 and CmNACNOR.The expression patterns of CmNAC34 and CmNAC-NOR were similar in melon tissues,and subcellular localization revealed their nuclear protein characteristics.We transformed CmNAC-NOR in melon and found that its overexpression resulted in early ripening fruits.Then,the yeast one-hybrid and dual luciferase reporter gene assays showed that the CmNAC34 protein can bind to the promoters of two glyoxalase(GLY)genes,which are involved in the abscisic acid signal pathway and associated with fruit regulation.These findings revealed the molecular characteristics,expression profiles,and functional patterns of the NAC family genes and provide new insights into the molecular mechanism by which CmNAC34 regulates climacteric fruit ripening.
基金supported by the Natural Science Foundation of Chongqing, China (CSTC, 2011BB1007)the Genetically Modified Organisms Breeding Major Projects of China (2009ZX08009-118B)
文摘Brassinosteroids（BRs）, a class of steroidal phytohormones are essential for many biological processes in plant. However, little is known about their roles in fruit development. Tomato is a highly valuable vegetable and has been adopted as the model species for studying fruit growth, development, and ripening. To understand the role of endogenous BRs in the development of tomato fruit, the expression patterns of three homologues of DWF4 gene were investigated and the transgenic tomato plants were generated in which the Gh DWF4 gene from upland cotton（Gossypium hirsutum L.） was ectopically expressed. The contents of main quality components were analyzed in fruits of transgenic tomato line and non-transgenic line（control plant, CP） when the fruit was mature. Sl CYP90B3 that possesses high homology with Gh DWF4 preferentially expressed in mature fruit. Significantly higher contents of soluble sugar, soluble proteins, and vitamin C were obtained in fruit of transgenic tomato lines compared with those in the CP. Furthermore, overexpressing Gh DWF4 promoted fruit growth and ripening. The weight per fruit was increased by about 23% in transgenic lines. In addition, overexpressing Gh DWF4 promoted the germination of transgenic tomato seeds and hypocotyl elongation of seedlings. These results indicated that overexpressing Gh DWF4 gene in tomato could increase the contents of many nutrients in fruit and accelerate fruit ripening. It is suggested that increased endogenous BRs in fruit affect the growth and development of tomato fruit and therefore improved the nutrient quality of tomato.
文摘A 1 250 bp cDNA fragment encoding β-mannanase, named MaMAN, was cloned from banana （Musa spp cv. Baxi） fruit using degenerate primers designed with reference to the conserved nucleic acid sequences of known β-mannanase genes by RT-PCR. Sequence analysis showed that MaMAN cDNA encompassed a 1 085 bp open-reading frame （ORF）, encoding a predicted polypeptide of 395 amino acids. Alignment of the deduced amino acid sequence of MaMAN and other putative β-mannanases showed that MaMAN has an identity of 86, 70, 69, 54, and 57%, respectively, to β-mannanases from tomato, lettuce, arabidopsis, carrot and oryza sativa. The catalytic residues： Asn203, Glu204, Glu318 and the active site residues： Arg86, His277, Tyr279, and Trp360, which were strictly conserved in the glycoside hydrolase family 5 to which all β-mannanases belonged, were found in MaMAN. Semi-quantitative RT-PCR revealed that the level of MaMAN transcript in the pulp increased during banana fruit ripening, suggesting that MaMAN was likely to be involved highly in banana fruit softening.
基金supported by the National Key Research and Development Program [Grant No.2018YFD1000200]the National Natural Science Foundation of China [Grant Nos.31872941,32072543]+2 种基金the Construction of Beijing Science and Technology Innovation and Service Capacity in Top Subjects [Grant No.CEFFPXM2019_014207_000032]the 111 Project [Grant No.B17043]the Engineering Research Center of Breeding and Propagation of Horticultural Crops,Ministry of Education。
文摘The regulation of apple(Malus domestica)fruit texture during ripening is complex and a fundamental determinant of its commercial quality.In climacteric fruit,ripening-related processes are regulated by ethylene(ET),and jasmonate(JA)is also involved in the ethylene biosynthesis pathway,mainly through the transcription factor MYC2.However,the molecular genetic mechanism for fruit ripening processes between the JA and ET signaling pathways still needs to be elucidated.In order to explore how JA regulates apple fruit ripening through ERF4,we used’Gala’and’Ralls Janet’fruit at different developmental stages as experimental materials to determine the fruit firmness and related gene expression analysis.Meanwhile,we carried out different hormone treatments on’Gala’fruit at ripening stage.Here,we show that ERF4 is a core JA signaling hub protein JASMONATE ZIM-DOMAIN(JAZ)interactor that affects ethylene signaling pathways.During fruit development,ERF4 represses the expression of ACS1 and ACO1 by interacting with JAZ,as well as with the JA-activated transcription factor MYC2.Ripening is promoted in JAZ-suppressed apples.Thus,ERF4 acts as a molecular link between ethylene and JA hormone signals,and the natural variation of the ERF4Ethylene-responsive binding factor-associated amphiphilic repression(EAR)motif decreases repression of ethylene biosynthesis genes.
基金supported by the Young Investigator Fund of Beijing Academy of Agricultural and Forestry Sciences(Grant No.202016)the Special innovation ability construction fund of Beijing Academy of Agricultural and Forestry Sciences(Grant Nos.20210437,20210402 and 20200427)+4 种基金the Collaborative innovation center of Beijing Academy of Agricultural and Forestry Sciences(Grant No.201915)Special innovation ability construction fund of Beijing Vegetable Research Center,Beijing Academy of Agriculture and Forestry Sciences(Grant No.2020112)the National Natural Science Foundation of China(Grant Nos.31772022 and 32072284)the China Agriculture Research System of MOF and MARA(Grant No.CARS-23)Beijing Municipal Science and Technology Commission(Grant Nos.Z191100008619004,Z191100004019010 and Z181100009618033)。
文摘Tomato is one of the most important vegetable crops in the world and is a model plant used to study the ripening of climacteric fleshy fruit.During the ripening process of tomato fruit,flavor and aroma metabolites,color,texture and plant hormones undergo significant changes.However,low temperatures delayed the ripening process of tomato fruit,inhibiting flavor compounds and ethylene production.Metabolomics and transcriptomics analyses of tomato fruit stored under low temperature(LT,5°C)and room temperature(RT,25°C)were carried out to investigate the effects of storage temperature on the physiological changes in tomato fruit after harvest.The results of transcriptomics changes revealed that the differentially expressed genes(DEGs)involved in tomato fruit ripening,including several kinds of transcription factors(TFs)(TCP,WRKY,MYB and bZIP),enzymes involved in cell wall metabolism[beta-galactosidase(β-GAL),pectinesterase(PE)and pectate lyase(PL),cellulose and cellulose synthase(CESA)],enzymes associated with fruit flavor and aroma[acetyltransferase(AT),malic enzyme(ME),lipoxygenase(LOX),aldehyde dehydrogenase(ALDH),alcohol dehydrogenase(ADH)and hexokinase(HK)],genes associated with heat stress protein 70 and genes involved in the production of plant hormones such as Ethylene responsive factor 1(ERF1),Auxin/indoleacetic acids protein(AUX/IAA),gibberellin regulated protein.Based on the above results,we constructed a regulatory network model of the effects of different temperatures during the fruit ripening process.According to the analysis of the metabolomics results,it was found that the contents of many metabolites in tomato fruit were greatly affected by storage temperature,including,organic acids(L-tartaric acid,a-hydroxyisobutyric acid and 4-acetamidobutyric acid),sugars(melezitose,beta-Dlactose,D-sedoheptulose 7-phosphate,2-deoxyribose 1-phosphate and raffinose)and phenols(coniferin,curcumin and feruloylputrescine).This study revealed the effects of storage temperature on postharvest tomato fruit and provided a basis for further understanding of the molecular biology and biochemistry of fruit ripening.
基金supported by the Biotechnology and Biological Sciences Research Council(Grant No.BB/M025918/1)National Natural Science Foundation of China(Grant No.32101656)+1 种基金Project of Guangxi Natural Science Foundation(Grant No.2020GXNSFDA297016)China Postdoctoral Science Foundation(Grant No.2021M691322).
文摘Fruit softening in tomato(Solanum lycopersicum)is closely associated with cell wall disassembly,which is brought about through the action of a range of cell wall structure-related enzymes and other proteins such as expansins.Xyloglucan endotransglucosylase/hydrolase(XTH)(EC 2.4.1.207 and/or EC 3.2.1.151)has been proposed to be key player involved in xyloglucan metabolism.SlXTH5 showed the highest expression level among all SlXTHs during tomato ripening.In this study,the role of SlXTH5 involved in tomato softening was investigated in CRISPR-based knockout mutants of SlXTH5.Loss-of-function of SlXTH5 in transgenic tomato lines resulted in slightly firmer fruit pericarp,but significantly decreased their color index compared with azygous wild type(WT)control fruits.Increased paste viscosity was detected in CRISPR mutants,indicating that the activity of SlXTH5 is responsible for maintaining cell wall structural integrity.Immunocytochemistry studies were performed using the monoclonal antibody probe LM25 to examine the localization and distribution of xyloglucan in the pericarp cells of the CRISPR mutant fruits.The data indicated more xyloglucan was retained in the pericarp of CRISPR mutant fruit than in WT control fruit.This study revealed the link between SlXTH5 and xyloglucan metabolism and indicated the potential of manipulating SlXTH5 to regulate fruit softening.
基金supported by the China Agriculture Research System of MOF and MARA (CARS-27)
文摘Fruit development and ripening is a complex procedure(Malus×domestica Borkh.)and can be caused by various factors such as cell structure,cell wall components,and cell wall hydrolytic enzymes.In our study,we focused on the variations in fruit firmness,cell wall morphology and components,the activity of cell wall hydrolytic enzymes and the expression patterns of associated genes during fruit development in two different types of apple cultivars,the hard-crisp cultivar and the loose-crisp cultivar.In this paper,the aim was to find out the causes of the texture variations between the different type cultivars.Cell wall materials(CWMs),hemicellulose and cellulose content were strongly associated with variations in fruit firmness during the fruit development.The content of water soluble pectin(WSP)and chelator soluble pectin(CSP)gradually increased,while the content of ionic soluble pectin(ISP)showed inconsistent trends in the four cultivars.The activities of polygalacturonase(PG),β-galactosidase(β-gal),cellulase(CEL),and pectate lyase(PL)gradually increased in four cultivars.And the activities of PG,β-gal,and CEL were higher in‘Fuji’and‘Honeycrisp’fruit with the fruit development,while the activity of PL of‘Fuji’and‘Honeycrisp’was lower than that of‘ENVY’and‘Modi’.Both four cultivars of fruit cells progressively became bigger as the fruit expanded,with looser cell arrangements and larger cell gaps.According to the qRT-PCR,the relative expression levels of MdACO and Mdβ-gal were notably enhanced.Our study showed that there were large differences in the content of ISP and hemicellulose,the activity of PL and the relative expression of Mdβ-gal between two different types of apple cultivars,and these differences might be responsible for the variations in the texture of the four cultivars.
基金supported by the National Natural Science Foundation of China (Grant Nos. 31722047, 31801848)LiaoNing Revitalization Talents Program (Grant No. XLYC1802019)
文摘Fruit ripening has been reported to be related to calcium(Ca),but the underlying mechanisms by which Ca regulates this process remain largely unknown.In order to study the changes of proteins and enriched phosphopeptides,we conducted TMT labeling,bio-material-based PTM enrichment based on mass spectrometry in Ca-treated‘Golden Delicious’(GD)apple fruit(Malus×domestica).This dataset presents a comprehensive overview of the critical pathways involved in fruit ripening.A total of 47 proteins and 124 phosphoproteins significantly changed in Ca-treated fruit,which are crucial for regulating the cell wall and cytoskeleton,Ca-mediated signaling and transport,ethylene production,protein fate,especially ubiquitination-based protein degradation,and primary and secondary metabolisms.Our results indicated that Ca inhibited the abundance of polygalacturonase(PG)activity and increased the phosphorylation level of CSLD3.PG and phosphorylation were involved in cell wall degradation,thereby delaying fruit softening.As a secondary messenger,Ca-mediated signaling subsequently triggered downstream mitogen-activated protein kinases(MAPK)cascades and activated the membrane,transport,and ROS signaling.Moreover,MdEIN2,a key enzyme involved in the ubiquitin of protein modification,increased at Ser753 and Ser758 in Ca-treated fruit.Furthermore,diverse primary and secondary metabolisms including glycolysis,fatty acid metabolism,and oxidation respiratory chain were modulated to prevent fruit softening.These results provide basic information from protein and phosphorylation levels for apple fruit ripening during storage,which may be helpful for apple fruit storage control.
基金supported by the National Natural Science Foundation of China (Grant No. 31872046)
文摘Abscisic acid(ABA)is a major regulator of non-climacteric fruit ripening;however,the role of ABA in the ripening of climacteric fruit is not clear.Here,as a typical climacteric fruit,apricots were used to investigate the role of ABA in fruit ripening.Based on weighted gene coexpression network analysis(WGCNA)of our previous transcriptome data,we treated‘Danxing’fruit with exogenous ABA and obtained ABA receptor genes,genes related to ABA biosynthesis and signal transduction,and analyzed the response of these candidate genes to exogenous ABA during fruit ripening.Subsequently,the full length of candidate PYLs genes were cloned,and their putative function were analyzed by phylogenetic analysis and protein structure domain analysis.And then the function of one candidate gene PaPYL9 was verified by using transgenic tomato.Furthermore,the response genes in transgenic tomato were screened by transcriptome sequencing,and ultimately the related regulatory network was proposed.The results showed that the injection of exogenous 1.89 mmol·L^(-1) ABA remarkably promoted fruit coloration,and increased the color index for red grapes(CIRG)and the total soluble solids(TSS)content,but significantly decreased the firmness and titratable acid(TA)content(p<0.01).Nordihydroguaiaretic acid(NDGA),the inhibitor of ABA,appeared to have the converse role in TA,TSS,CIRG and firmness,during the ripening process.One NCED(9-cis-epoxycarotenoiddioxygenase)and five ABA receptor genes related to signal transduction were mined from the transcriptome data of apricot fruit through WGCNA.Compared with the control,the expression levels of NCED1,PYL9(PYR/PYL/RCAR),SnRK2(SUCROSE NON-FERMENTING1(SNF1)-RELATED PROTEIN KINASE 2S),and ABF2(ABRE-binding bZIP transcription)were induced dramatically by ABA treatment(p<0.01),while NDGA treatment significantly inhibited their expression.Based on gene expression and protein domain analysis,we inferred that PaPYL9 is putatively involved in apricot fruit ripening.Overexpression of PaPYL9 in Micro-TOM tomatoes resulted in the promotion of early ripening.Simultaneously,the expression levels of genes related ethylene biosynthesis,chlorophyll degradation,fruit softening,flavor formation,pigment synthesis,and metabolism were all significantly induced in overexpression of PaPYL9 tomatoes.This indicates the central role of ABA in climacteric fruit ripening.A regulatory network was tentatively proposed,laying the foundation to unveil the molecular mechanism of the regulatory role of PaPYL9 in fruit ripening.
基金supported by the National Natural Science Foundation of China (31301761)the China Scholarship Council (201608130248)the Second Round of the Youth Top-Notch Talent Support Programs of Hebei Province, China (2019)。
文摘Salicylic acid(SA) plays a pivotal role in delaying fruit ripening and senescence. However, little is known about its underlying mechanism of action. In this study, RNA sequencing was conducted to analyze and compare the transcriptome profiles of SA-treated and control pear fruits. We found a total of 159 and 419 genes differentially expressed between the SA-treated and control pear fruits after 12 and 24 h of treatment, respectively. Among these differentially expressed genes(DEGs), 125 genes were continuously differentially expressed at both treatment times, and they were identified as candidate genes that might be associated with SA-regulated fruit ripening and senescence. Bioinformatics analysis results showed that 125 DEGs were mainly associated with plant hormone biosynthesis and metabolism, cell wall metabolism and modification, antioxidant systems, and senescence-associated transcription factors. Additionally, the expression of several candidate DEGs in ripening and senescent pear fruits after SA treatments were further validated by quantitative real-time PCR(qRT-PCR). This study provides valuable information and enhances the understanding of the comprehensive mechanisms of SA-meditated pear fruit ripening and senescence.
基金Project (No. 30371001) supported by the National Natural Science Foundation of China
文摘The characteristics of fruit ripening and expression of ripening-related genes were investigated in epi, an ethylene overproduction mutant of tomato (Lycopersicon esculentum Mill.). The epi produces apparently more ethylene than its wild type VFN8 at every stage of vegetative and fruit growth and ripening; compared to VFN8, the epi fruit showed higher CO2 evolution, faster descending of chlorophyll, slightly quicker increase of carotenoid and lycopene, and faster reduction in pericarp firmness during maturation and ripening; and the mRNAs of three ripening-related genes including E8, pTOM5 and pTOM6 were at higher levels in epi. The ripening-related characteristics changing of the fruit are consistent with the increase of ethylene production and ripening-related genes expression. These results suggest that epi mutation possibly did not affect the ethylene perception and signaling during fruit ripening, and that the modified characteristics of fruit ripening possibly resulted from the ethylene over- production and increased expression of ripening-related genes.
基金supported by National Natural Science Foundation of China(30471180)Nature Science Foundation of Chongqing City,China(8045,2004-56).
文摘The purpose of this study is to explore the influence of co-suppressing tomato ACC oxidase Ⅰ on the expression of fruit ripening-related and pathogenesis-related protein genes, and on the biosynthesis of endogenous ethylene and storage ability of fruits. Specific fragments of several fruit ripening-related and pathogenesis-related protein genes from tomato （Lycopersicon esculentum） were cloned, such as the l-aminocyclopropane-1-carboxylic acid oxidase 1 gene （LeAC01）, 1- aminocyclopropane-l-carboxylic acid oxidase 3 gene （LeAC03）, EIN3-binding F-box 1 gene （LeEBF1）, pathogenesis-related protein 1 gene （LePR1）, pathogenesis-related protein 5 gene （LePR5）, and pathogenesis-related protein osmotin precursor gene （LeNP24） by PCR or RT-PCR. Then these specific DNA fragments were used as probes to hybridize with the total RNAs extracted from the wild type tomato Ailsa Craig （AC＋＋） and the LeAC01 co-suppression tomatoes （V1187 and T4B）, respectively. At the same time, ethylene production measurement and storage experiment of tomato fruits were carded out. The hybridization results indicated that the expression of fruit ripening-related genes such as LeACO3 and LeEBF1, and pathogenesis-related protein genes such as LePR1, LePR5, and LeNP24, were reduced sharply, and the ethylene production in the fruits, wounded leaves decreased and the storage time of ripening fruits was prolonged, when the expression of LeACO1 gene in the transgenic tomato was suppressed. In the co-suppression tomatoes, the expression of fruit ripening-related and pathogenesis-related protein genes were restrained at different degrees, the biosynthesis of endogenous ethylene decreased and the storage ability of tomato fruits increased.
文摘Activities of NAD kinase(NADK)and NADP phosphatase and relationship between the two enzymes and temperature, respiration, ethylene production and trifluoperazine(TFP) were studied during ripening and senescence of strawberry and tomato fruits after harvest at 4℃ and 20℃. The activity of NAD kinase in strawberry decreased slowly during first four days, then increased gradually. The NADP phosphatase activity increased at the second day, decreased the next day,then increased again. In tomato fruit, the activities of NAD kinase and NADP phosphatase increased at the second day, decreased with the ripening and senescence of the fruit. The change trend of NAD kinase and respiration in the two fruits were similar, the same were NADP phosphatase and ethylene production. TFP enhanced the activity of NAD kinase and had little effect on NADP phosphatase. Low temperature(4℃) activated the NAD kinase and reduced the activity of NADP phosphatase. These results indicated that the NAD kinase and NADP phosphatase were related to the ripening and senescence of strawberry and tomato fruits. The activation of NAD kinase probably postponed the ripening and senescence of the fruits.
基金supported by the National Natural Science Fundation of China(30840016,30570134)the Key Technologies R&D Program of China during the 11th Five-Year Plan period(2006BAD22B01)the Natural Science Fundation of Jiangsu Province,China(BK 2007076)
文摘The fruits of peach cultivar Yuhua 3 were used as materials to investigate the changes of active oxygen and related enzymes in mitochondria respiratory metabolism during ripening of peach fruit,involving their influence on the proceeding of peach fruit senescence.The results showed that the large decrease in firmness occurred between maturity II and IV.The decrease in firmness coincided with an increase in respiratory intensity.Obvious peaks of respiratory intensity lagging to the rapid change of fruit firmness could be shown during peach ripening.Reactive oxygen species(ROS)had a cumulative process and positively correlated with respiratory intensity.During peach ripening,the content of Ca^2+increased,the activities of succinic dehydrogenase(SDH),cytochrome C oxidase(CCO),H+-ATPase,and Ca^2+-ATPase decreased varying in different degree at the later step of ripening.These suggested a close relationship existed between ROS metabolism and mitochondrial respiration,namely,both ROS metabolism and mitochondrial respiration probably played important roles in ripening and senescing of peach fruit.
基金Supported by National Project of Scientific and Technical Supporting Programs Funded by Ministry of Science and Technology of China (No.2006BAD22B01)National Natural Science Foundation of China (No.30800767)Postdoctoral Fund of China (No.20080430725)
文摘Fruit ripening is a complex process and is regulated by many factors. Ethylene and polygalacturonase （PG）, lipoxygenase （LOX）, expansin （EXP） are all critical regulating factors in fruit ripening and softening process. With antisense ACS tomato, Nr mutant tomato and cultivated tomato as materials, Northern blot hybridization showed that PG, LeEXP1 and LOXexpressed differently in different parts of cultivated tomato fruit during ripening, which was related to fruit ripening. The ripening process of columella and radial pericarp was faster than pericarp. In both Nr mutant and antisense ACS transgenic tomato fruit, expression levels ofPG, LeEXPI and LOXwere generally lower than those in cultivated fruit but still related to fruit ripening. The expression levels ofPG, LeEXP1 and LOX increased in the mature green tomato fruits after 0.5 h treatment with ethylene （100 μL/L）. These results indicate that gene expression ofPG, LeEXP1 and LOXwere positively regulated by ethylene. The time and cumulative effect of the concentration exists in the expression of PG regulated by ethylene. The regulation of LOX expression mainly depended on the fruit development after great amount of ethylene was produced. PG played a major role in ripening and softening of tomato fruit, and cooperated with the regulation of EXP and LOX.
基金supported by NSFC grants(32261160371 and 92254307)the Science and Technology Project of Hubei Province(2024AFE005)+2 种基金Young Scientist Fostering Funds for the National Key Laboratory for Germplasm Innovation and Utilization of Horticultural Crops(Horti-PY-2023-001)the Postdoctoral Fellowship Program of CPSF under grant number GZC20241391a China Postdoctoral Science Foundation(2025M773723).
文摘Fruit ripening is a programmed process involving dramatic physiological changes.It is regulated by various phytohormones such as ethylene and abscisic acid(ABA),which activate ripening-related gene expression and affect respiration,metabolism,and cell homeostasis(Liu et al.,2015).Autophagy is a key cellular recycling mechanism that is induced during cellular reprogramming(Sun et al.,2021),and its activity is also upregulated during fruit ripening in many species.However,a few independent studies have come up with different conclusions,adding complexity to the understanding of the contribution of autophagy to fruit ripening.Here,we focus on recent discoveries and discuss possible roles of autophagy in fruit ripening.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.31830071,32202561)the earmarked fund for CARS(Grant No.CARS-31)。
文摘Banana fruit ripening is a highly regulatory process involving various layers consisting of transcriptional regulation,epigenetic factor,and post-translational modification.Previously,we reported that MaERF11 cooperated with MaHDA1 to precisely regulate the transcription of ripening-associated genes via histone deacetylation.However,whether MaERF11 is subjected to post-translational modification during banana ripening is largely unknown.In this study,we found that MaERF11 targeted a subset of starch degradation-related genes using the DNA affinity purification sequence(DAP-Seq)approach.Electrophoretic mobility shift assay(EMSA)and dual-luciferase reporter assay(DLR)demonstrated that MaERF11 could specifically bind and repress the expression of the starch degradation-related genes MaAMY3,MaBAM2 and MaGWD1.Further analyses of yeast two-hybrid(Y2H),bimolecular fluorescence complementation(BiFC)and Luciferase complementation imaging(LCI)assays indicated that MaERF11 interacted with the ubiquitin E3 ligase MaRFA1,and this interaction weakened the MaERF11-mediated transcriptional repression capacity.Collectively,our results suggest an additional regulatory layer in which MaERF11 regulates banana fruit ripening and expands the regulatory network in fruit ripening at the post-translational modification level.
