A two-year field experiment(2014-2016;Zanjan,Iran)was conducted to monitor potential diversity pattern and adaptability power among 18 Iranian saffron ecotypes under Zanjan climatological conditions using seven flower...A two-year field experiment(2014-2016;Zanjan,Iran)was conducted to monitor potential diversity pattern and adaptability power among 18 Iranian saffron ecotypes under Zanjan climatological conditions using seven flower-related and three qualitative traits(crocin,picrocrocin,and safranal,determined by UV-visible spectra),and analyzed by supervised and unsupervised approaches.A range of variability was recorded among the ecotypes,and despite some exceptions,overall,saffron corms produced higher amounts of studied features across the second year.The Feizabad ecotype was recommended to acquire maximum qualitative criteria(category I;based on ISO Normative 3632 grading system),while for flower-related parameters several ecotypes(e.g.,Ghaien,Bardeskan,Torbat-Jam,and Gonabad)could be applied for Zanjan climatological conditions.Based on the results of Leave-One-Out Cross-Validation(LOOCV),various prediction values were computed for all 10 classifiers of LDA,QDA,FDA,MDA,RDA,Naive Bayes,Decision Tree,Linear SVM,Radial SVM,and Random Forest in terms of accuracy,sensitivity and specificity parameters.Among which,Random Forest and LDA with the values of 0.91 and 0.78 possessed the highest and the lowest amounts of accuracy,respectively.Finally,considering the highest accuracy value of the superior classification model of Random forest,both feature subsets of“FFW,FDW,Picrocrocin,Safranal,and Crocin”and“SFW,FDW,Picrocrocin,Safranal,and Crocin”were nominated as the most powerful elements(comparing to the remaining 1021 feature subsets)to make accurate discrimination between Khorasan and non-Khorasan saffron ecotypes.The results,overall,revealed that saffron ecotypes followed different responses under Zanjan climatological circumstances,and Random Forest is more suitable for accurately predicting saffron corms from different provenances.展开更多
Crocus sativus (saffron) is a globally autumn-flowering plant, and its stigmas are the most expensive spice and valuable herb medicine. Crocus specialized metabolites, crocins, are biosynthesized in distant species, G...Crocus sativus (saffron) is a globally autumn-flowering plant, and its stigmas are the most expensive spice and valuable herb medicine. Crocus specialized metabolites, crocins, are biosynthesized in distant species, Gardenia (eudicot) and Crocus (monocot), and the evolution of crocin biosynthesis remains poorly understood. With the chromosome-level Crocus genome assembly, we revealed that two rounds of lineage-specific whole genome triplication occurred, contributing important roles in the production of carotenoids and apocarotenoids. According to the kingdom-wide identification, phylogenetic analysis, and functional assays of carotenoid cleavage dioxygenases (CCDs), we deduced that the duplication, site positive selection, and neofunctionalization of Crocus-specific CCD2 from CCD1 members are responsible for the crocin biosynthesis. In addition, site mutation of CsCCD2 revealed the key amino acids, including I143, L146, R161, E181, T259, and S292 related to the catalytic activity of zeaxanthin cleavage. Our study provides important insights into the origin and evolution of plant specialized metabolites, which are derived by duplication events of biosynthetic genes.展开更多
Anchorene,identified as an endogenous bioactive carotenoid-derived dialdehyde and diapocarotenoid,affects root development by modulating auxin homeostasis.However,the precise interaction between anchorene and auxin,as...Anchorene,identified as an endogenous bioactive carotenoid-derived dialdehyde and diapocarotenoid,affects root development by modulating auxin homeostasis.However,the precise interaction between anchorene and auxin,as well as the mechanisms by which anchorene modulates auxin levels,remain largely elusive.In this study,we conducted a comparative analysis of anchorene's bioactivities alongside auxin and observed that anchorene induces multifaceted auxin-like effects.Through genetic and pharmacological examinations,we revealed that anchorene's auxin-like activities depend on the indole-3-pyruvate-dependent auxin biosynthesis pathway,as well as the auxin inactivation pathway mediated by Group II Gretchen Hagen 3(GH3)proteins that mainly facilitate the conjugation of indole-3-acetic acid(IAA)to amino acids,leading to the formation of inactivated storage forms.Our measurements indicated that anchorene treatment elevates IAA levels while reducing the quantities of inactivated IAA–amino acid conjugates and ox IAA.RNA sequencing further revealed that anchorene triggers the expression of numerous auxin-responsive genes in a manner reliant on Group II GH3s.Additionally,our in vitro enzymatic assays and biolayer interferometry(BLI)assay demonstrated anchorene's robust suppression of GH3.17-mediated IAA conjugation with glutamate.Collectively,our findings highlight the significant role of carotenoid-derived metabolite anchorene in modulating auxin homeostasis,primarily through the repression of GH3-mediated IAA conjugation and inactivation pathways,offering novel insights into the regulatory mechanisms of plant bioactive apocarotenoids.展开更多
Abscisic acid(ABA)is an important carotenoid-derived phytohormone that plays essential roles in plant response to biotic and abiotic stresses as well as in various physiological and developmental processes.In Arabidop...Abscisic acid(ABA)is an important carotenoid-derived phytohormone that plays essential roles in plant response to biotic and abiotic stresses as well as in various physiological and developmental processes.In Arabidopsis,ABA biosynthesis starts with the epoxidation of zeaxanthin by the ABA DEFICIENT 1(ABA1)enzyme,leading to epoxycarotenoids;e.g.,violaxanthin.The oxidative cleavage of 9-cis-epoxycaro-tenoids,a key regulatory step catalyzed by 9-C/S-EPOXYCAROTENOID DIOXYGENASE,forms xanthoxin,which is converted in further rea.ctions mediated by ABA DEFICIENT 2(ABA2),ABA DEFICIENT 3(ABA3),and ABSCISIC ALDEHYDE OXIDASE 3(AAO3)into ABA.By combining genetic and biochemical approaches,we unravel here an ABA1-independent ABA biosynthetic pathway starting upstream of zeaxanthin.We iden-tified the carotenoid cleavage products(i.e.,apocarotenoids,β-apo-11-carotenal,9-cis-β-apo-11-carotenal,3-OH-β-apo-11-carotenal,and 9-cis-3-OH-β-apo-11-carotenal)as intermediates of this ABA1-independent ABA biosynthetic pathway.Using labeled compounds,we showed thatβ-apo-11-carotenal,9-cis-β-apo-11-carotenal,and 3-OH-β-apo-11-carotenal are successively converted into 9-cis-3-OH-β-apo-11-carotenal,xanthoxin,and finally into ABA in both Arabidopsis and rice.When applied to Arabidopsis,theseβ-apo-11-carotenoids exert ABA biological functions,such as maintaining seed dormancy and inducing the expression of ABA-responsive genes.Moreover,the transcdptomic analysis revealed a high overlap of differentially expressed genes regulated byβ-apo-11-carotenoids and ABA,suggesting thatβ-apo-11-carot-enoids exert ABA-independent regulatory activities.Taken together,our study identifies a biological function for the common plant metabolites,β-apo-11-carotenoids,extends our knowledge about ABA biosynthesis,and provides new insights into plant apocarotenoid metabolic networks.展开更多
Zaxinone is an apocarotenoid regulatory metabolite required for normal rice growth and development.In addition,zaxinone has a large application potential in agriculture,due to its growth-promoting activity and capabil...Zaxinone is an apocarotenoid regulatory metabolite required for normal rice growth and development.In addition,zaxinone has a large application potential in agriculture,due to its growth-promoting activity and capability to alleviate infestation by the root parasitic plant Striga through decreasing strigolactone(SL)production.However,zaxinone is poorly accessible to the scientific community because of its laborious organic synthesis that impedes its further investigation and utilization.In this study,we developed easy-to-synthesize and highly efficient mimics of zaxinone(MiZax).We performed a structure-activity relationship study using a series of apocarotenoids distinguished from zaxinone by different structural features.Using the obtained results,we designed several phenyl-based compounds synthesized with a high-yield through a simple method.Activity tests showed that MiZax3 and MiZax5 exert zaxinone activity in rescuing root growth of a zaxinone-deficient rice mutant,promoting growth,and reducing SL content in roots and root exudates of wild-type plants.Moreover,these compounds were at least as efficient as zaxinone in suppressing transcript level of SL biosynthesis genes and in alleviating Striga infestation under greenhouse conditions,and did not negatively impact mycorrhization.Taken together,MiZax are a promising tool for elucidating zaxinone biology and investigating rice development,and suitable candidates for combating Striga and increasing crop growth.展开更多
Carotenoids and apocarotenoids act as phytohormones and volatile precursors that influence plant development and confer aesthetic and nutritional value critical to consumer preference.Citrus fruits display considerabl...Carotenoids and apocarotenoids act as phytohormones and volatile precursors that influence plant development and confer aesthetic and nutritional value critical to consumer preference.Citrus fruits display considerable natural variation in carotenoid and apocarotenoid pigments.In this study,using an integrated genetic approach we revealed that a 5;c/s-regulatory change at CCD4b encoding CAROTENOID CLEAVAGE DIOXYGENASE 4b is a major genetic determinant of natural variation in C3 0 apocarotenoids responsible for red coloration of citrus peel.Functional analyses demonstrated that in addition the known role in synthesizing 3-citraurin,CCD4b is also responsible for the production of another important C3 0 apocarotenoid pigment,p-citraurinene.Furthermore,analyses of the CCD4b promoter and transcripts from various citrus germplasm accessions established a tight correlation between the presence of a putative 5'c/s-regulatory enhancer within an MITE transposon and the enhanced allelic expression of CCD4b in C3 0 apocarotenoid-rich red-peeled accessions.Phylogenetic analysis provided further evidence that functional diversification of CCD4b and naturally occurring variation of the CCD4b promoter resulted in the stepwise evolution of red peels in mandarins and their hybrids.Taken together,our findings provide new insights into the genetic and evolutionary basis of apocarotenoid diversity in plants,and would facilitate breeding efforts that aim to improve the nutritional and aesthetic value of citrus and perhaps other fruit crops.展开更多
文摘A two-year field experiment(2014-2016;Zanjan,Iran)was conducted to monitor potential diversity pattern and adaptability power among 18 Iranian saffron ecotypes under Zanjan climatological conditions using seven flower-related and three qualitative traits(crocin,picrocrocin,and safranal,determined by UV-visible spectra),and analyzed by supervised and unsupervised approaches.A range of variability was recorded among the ecotypes,and despite some exceptions,overall,saffron corms produced higher amounts of studied features across the second year.The Feizabad ecotype was recommended to acquire maximum qualitative criteria(category I;based on ISO Normative 3632 grading system),while for flower-related parameters several ecotypes(e.g.,Ghaien,Bardeskan,Torbat-Jam,and Gonabad)could be applied for Zanjan climatological conditions.Based on the results of Leave-One-Out Cross-Validation(LOOCV),various prediction values were computed for all 10 classifiers of LDA,QDA,FDA,MDA,RDA,Naive Bayes,Decision Tree,Linear SVM,Radial SVM,and Random Forest in terms of accuracy,sensitivity and specificity parameters.Among which,Random Forest and LDA with the values of 0.91 and 0.78 possessed the highest and the lowest amounts of accuracy,respectively.Finally,considering the highest accuracy value of the superior classification model of Random forest,both feature subsets of“FFW,FDW,Picrocrocin,Safranal,and Crocin”and“SFW,FDW,Picrocrocin,Safranal,and Crocin”were nominated as the most powerful elements(comparing to the remaining 1021 feature subsets)to make accurate discrimination between Khorasan and non-Khorasan saffron ecotypes.The results,overall,revealed that saffron ecotypes followed different responses under Zanjan climatological circumstances,and Random Forest is more suitable for accurately predicting saffron corms from different provenances.
基金This work was supported by the National Natural Science Foundation of China(81973424,82073966,82204346)the CAMS Innovation Fund for Medical Sciences(CIFMS)(Grant No.2021-I2M-1-029,China)+2 种基金the National Key R&D Program of China(2023YFC3504800)the Fundamental Research Funds for the Central public welfare research institutes(ZZ16-YQ-047,ZZ16-ND-10-02,China)the Key Scientific Research Foundation of the Higher Education Institutions of Anhui Province,China(KJ2021A0235).
文摘Crocus sativus (saffron) is a globally autumn-flowering plant, and its stigmas are the most expensive spice and valuable herb medicine. Crocus specialized metabolites, crocins, are biosynthesized in distant species, Gardenia (eudicot) and Crocus (monocot), and the evolution of crocin biosynthesis remains poorly understood. With the chromosome-level Crocus genome assembly, we revealed that two rounds of lineage-specific whole genome triplication occurred, contributing important roles in the production of carotenoids and apocarotenoids. According to the kingdom-wide identification, phylogenetic analysis, and functional assays of carotenoid cleavage dioxygenases (CCDs), we deduced that the duplication, site positive selection, and neofunctionalization of Crocus-specific CCD2 from CCD1 members are responsible for the crocin biosynthesis. In addition, site mutation of CsCCD2 revealed the key amino acids, including I143, L146, R161, E181, T259, and S292 related to the catalytic activity of zeaxanthin cleavage. Our study provides important insights into the origin and evolution of plant specialized metabolites, which are derived by duplication events of biosynthetic genes.
基金supported by the National Natural Science Foundation of China(32170271)by the Natural Science Foundation of Henan Province(222300420024)the Project of Sanya Yazhou Bay Science and Technology City(SCKJ-JYRC-2022-19)。
文摘Anchorene,identified as an endogenous bioactive carotenoid-derived dialdehyde and diapocarotenoid,affects root development by modulating auxin homeostasis.However,the precise interaction between anchorene and auxin,as well as the mechanisms by which anchorene modulates auxin levels,remain largely elusive.In this study,we conducted a comparative analysis of anchorene's bioactivities alongside auxin and observed that anchorene induces multifaceted auxin-like effects.Through genetic and pharmacological examinations,we revealed that anchorene's auxin-like activities depend on the indole-3-pyruvate-dependent auxin biosynthesis pathway,as well as the auxin inactivation pathway mediated by Group II Gretchen Hagen 3(GH3)proteins that mainly facilitate the conjugation of indole-3-acetic acid(IAA)to amino acids,leading to the formation of inactivated storage forms.Our measurements indicated that anchorene treatment elevates IAA levels while reducing the quantities of inactivated IAA–amino acid conjugates and ox IAA.RNA sequencing further revealed that anchorene triggers the expression of numerous auxin-responsive genes in a manner reliant on Group II GH3s.Additionally,our in vitro enzymatic assays and biolayer interferometry(BLI)assay demonstrated anchorene's robust suppression of GH3.17-mediated IAA conjugation with glutamate.Collectively,our findings highlight the significant role of carotenoid-derived metabolite anchorene in modulating auxin homeostasis,primarily through the repression of GH3-mediated IAA conjugation and inactivation pathways,offering novel insights into the regulatory mechanisms of plant bioactive apocarotenoids.
基金This work was supported by baseline funding and the Research Grants Prog ram-Round 4(CRG4)baseline funding from King Abdullah University of Science and Technology to S.A.-B.National Natural Science Foundation of China(funds 31900245 and 32170271)given to K.-P.J.
文摘Abscisic acid(ABA)is an important carotenoid-derived phytohormone that plays essential roles in plant response to biotic and abiotic stresses as well as in various physiological and developmental processes.In Arabidopsis,ABA biosynthesis starts with the epoxidation of zeaxanthin by the ABA DEFICIENT 1(ABA1)enzyme,leading to epoxycarotenoids;e.g.,violaxanthin.The oxidative cleavage of 9-cis-epoxycaro-tenoids,a key regulatory step catalyzed by 9-C/S-EPOXYCAROTENOID DIOXYGENASE,forms xanthoxin,which is converted in further rea.ctions mediated by ABA DEFICIENT 2(ABA2),ABA DEFICIENT 3(ABA3),and ABSCISIC ALDEHYDE OXIDASE 3(AAO3)into ABA.By combining genetic and biochemical approaches,we unravel here an ABA1-independent ABA biosynthetic pathway starting upstream of zeaxanthin.We iden-tified the carotenoid cleavage products(i.e.,apocarotenoids,β-apo-11-carotenal,9-cis-β-apo-11-carotenal,3-OH-β-apo-11-carotenal,and 9-cis-3-OH-β-apo-11-carotenal)as intermediates of this ABA1-independent ABA biosynthetic pathway.Using labeled compounds,we showed thatβ-apo-11-carotenal,9-cis-β-apo-11-carotenal,and 3-OH-β-apo-11-carotenal are successively converted into 9-cis-3-OH-β-apo-11-carotenal,xanthoxin,and finally into ABA in both Arabidopsis and rice.When applied to Arabidopsis,theseβ-apo-11-carotenoids exert ABA biological functions,such as maintaining seed dormancy and inducing the expression of ABA-responsive genes.Moreover,the transcdptomic analysis revealed a high overlap of differentially expressed genes regulated byβ-apo-11-carotenoids and ABA,suggesting thatβ-apo-11-carot-enoids exert ABA-independent regulatory activities.Taken together,our study identifies a biological function for the common plant metabolites,β-apo-11-carotenoids,extends our knowledge about ABA biosynthesis,and provides new insights into plant apocarotenoid metabolic networks.
基金the Bill&Melinda Gates Foundation(grant no.OPP1194472)a Competitive Research Grant(CRG2017)to S.A.-B.from King Abdullah University of Science and Technology(KAUST)+2 种基金the Core Research for Evolutional Science and Technology(CREST)Programthe SATREPS Program of the Japan Science and Technology Agency(JST)JSPS Grant-in-Aid for Scientific Research(grant no.18H03939)to T.A.
文摘Zaxinone is an apocarotenoid regulatory metabolite required for normal rice growth and development.In addition,zaxinone has a large application potential in agriculture,due to its growth-promoting activity and capability to alleviate infestation by the root parasitic plant Striga through decreasing strigolactone(SL)production.However,zaxinone is poorly accessible to the scientific community because of its laborious organic synthesis that impedes its further investigation and utilization.In this study,we developed easy-to-synthesize and highly efficient mimics of zaxinone(MiZax).We performed a structure-activity relationship study using a series of apocarotenoids distinguished from zaxinone by different structural features.Using the obtained results,we designed several phenyl-based compounds synthesized with a high-yield through a simple method.Activity tests showed that MiZax3 and MiZax5 exert zaxinone activity in rescuing root growth of a zaxinone-deficient rice mutant,promoting growth,and reducing SL content in roots and root exudates of wild-type plants.Moreover,these compounds were at least as efficient as zaxinone in suppressing transcript level of SL biosynthesis genes and in alleviating Striga infestation under greenhouse conditions,and did not negatively impact mycorrhization.Taken together,MiZax are a promising tool for elucidating zaxinone biology and investigating rice development,and suitable candidates for combating Striga and increasing crop growth.
基金the National Key R&D Program of China(2018YFD1000200)the National Natural Science Foundation of China(no.31630065,31330066 and 31521092)China Agriculture Research System(CARS-27)the 111 project(B13034),and a China Council Scholarship(to X.Z.).
文摘Carotenoids and apocarotenoids act as phytohormones and volatile precursors that influence plant development and confer aesthetic and nutritional value critical to consumer preference.Citrus fruits display considerable natural variation in carotenoid and apocarotenoid pigments.In this study,using an integrated genetic approach we revealed that a 5;c/s-regulatory change at CCD4b encoding CAROTENOID CLEAVAGE DIOXYGENASE 4b is a major genetic determinant of natural variation in C3 0 apocarotenoids responsible for red coloration of citrus peel.Functional analyses demonstrated that in addition the known role in synthesizing 3-citraurin,CCD4b is also responsible for the production of another important C3 0 apocarotenoid pigment,p-citraurinene.Furthermore,analyses of the CCD4b promoter and transcripts from various citrus germplasm accessions established a tight correlation between the presence of a putative 5'c/s-regulatory enhancer within an MITE transposon and the enhanced allelic expression of CCD4b in C3 0 apocarotenoid-rich red-peeled accessions.Phylogenetic analysis provided further evidence that functional diversification of CCD4b and naturally occurring variation of the CCD4b promoter resulted in the stepwise evolution of red peels in mandarins and their hybrids.Taken together,our findings provide new insights into the genetic and evolutionary basis of apocarotenoid diversity in plants,and would facilitate breeding efforts that aim to improve the nutritional and aesthetic value of citrus and perhaps other fruit crops.
