The phenolic acids in free phenolic acid (FPHA), methanol-soluble phenolic ester (MSPE), and methanol-soluble phenolic glycoside (MSPG) fractions of two carob products, natural carob-pod flour (CPF) and commercial car...The phenolic acids in free phenolic acid (FPHA), methanol-soluble phenolic ester (MSPE), and methanol-soluble phenolic glycoside (MSPG) fractions of two carob products, natural carob-pod flour (CPF) and commercial carob-pod flour (CCPF), were identified and quantified using high-performance liquid chromatography-mass spectrometry (HPLC-MS). Six phenolic acids were identified in the carob flours (gallic acid, protocatechuic acid, gentisic acid, syringic acid, p- coumaric acid, and sinapic acid). Gallic acid was the major phenolic acid;and its concentrations in CCPF were substantially higher than in CPF (135 - 166 and 85.2 - 91.3 mg/g dw, respectively). The concentrations of p-coumaric acid and sinapic acid were also higher in CCPF than in CPF. In contrast, the concentrations of protocatechuic acid and gentisic acid were generally lower in CCPF than in CPF, with the only exception being gentisic acid glycosides. Both carob-pod flours contained almost the same amount of sinapic acid and syringic acid. The total phenolic contents of the FPHA, MSPE, and MSPG fractions of CPF were found to be 44%, 38%, and 69% that of the respective fractions of CCPF. Correspondingly, the FPHA, MSPE, and MSPG fractions of CCPF had higher free radical-scavenging activity (28.4%, 33.1%, and 26.2%, respectively) than the corresponding fractions of CPF (9.2%, 28.0%, and 9.2%, respectively). Notably, the FPHA and MSPG fractions of each sample had very similar scavenging activity while the MSPE fraction always had higher activity. The FPHA and MSPG fractions of CPF had the lowest activities.展开更多
Plants have evolved several strategies to cope with the ever-changing environment.One example of this is given by seed germination,which must occur when environmental conditions are suitable for plant life.In the mode...Plants have evolved several strategies to cope with the ever-changing environment.One example of this is given by seed germination,which must occur when environmental conditions are suitable for plant life.In the model system Arabidopsis thaliana seed germination is induced by light;however,in nature,seeds of several plant species can germinate regardless of this stimulus.While the molecular mechanisms underlying light-induced seed germination are well understood,those governing germination in the dark are still vague,mostly due to the lack of suitable model systems.Here,we employ Cardamine hirsuta,a close relative of Ara-bidopsis,as a powerful model system to uncover the molecular mechanisms underlying light-independent germination.By comparing Cardamine and Arabidopsis,we show that maintenance of the pro-germination hormone gibberellin(GA)levels prompt Cardamine seeds to germinate under both dark and light conditions.Using genetic and molecular biology experiments,we show that the Cardamine DOF transcriptional repressor DOF AFFECTING GERMINATION 1(ChDAG1),homologous to the Arabidopsis transcription factor DAG1,is involved in this process functioning to mitigate GA levels by negatively regulating GA biosynthetic genes ChGA3OX1 and ChGA3OX2,independently of light conditions.We also demonstrate that this mechanism is likely conserved in other Brassicaceae species capable of germinating in dark conditions,such as Lepidium sativum and Camelina sativa.Our data support Cardamine as a new model system suitable for studying light-independent germination studies.Exploiting this system,we have also resolved a long-standing question about the mechanisms controlling light-independent germination in plants,opening new frontiers for future research.展开更多
A series of reticulated Arabidopsis thaliana mutants were previously described. All mutants show a reticulate leaf pattern, namely green veins on a pale leaf lamina. They have an aberrant mesophyll structure but an in...A series of reticulated Arabidopsis thaliana mutants were previously described. All mutants show a reticulate leaf pattern, namely green veins on a pale leaf lamina. They have an aberrant mesophyll structure but an intact layer of bundle sheath cells around the veins. Here, we unravel the function of the previously described reticulated EMS-mutant dovl （differential development of vascular associated cells 1）. By positional cloning, we identified the mutated gene, which encodes glutamine phosphoribosyl pyrophosphate aminotransferase 2 （ATase2）, an enzyme catalyzing the first step of purine nucleotide biosynthesis, dovl is allelic to the previously characterized cial-2 mutant that was isolated in a screen for mutants with impaired chloroplast protein import. We show that purine-derived total cytokinins are lowered in clovl and crosses with phytohormone reporter lines revealed differential reporter activity patterns in dovl. Metabolite profiling unraveled that amino acids that are involved in purine biosynthesis are increased in dovl. This study identified the mo- lecular basis of an established mutant line, which has the potential for further investigation of the interaction between metabolism and leaf development.展开更多
基金Some of the chemicals,reagents,and instrumentation were purchased using funds awarded by the Research Fund of Karadeniz Technical University(Project Nos.2003.111.004.5 and 2005.111.004.2) the Scientific and Technological Research Council of Turkey(TUBI-TAK+3 种基金TBAG Project No.103T152)JG and MS were supported by the Academy of Sciences of the Czech Re-public(KAN 200380801)the Centre of the Region Hanáfor Biotechnological and Agricultural Research(grant No.ED0007/01/01)and by the Czech Science Founda-tion(GACR P503/12/P166).The authors gratefully ac-knowledge this support.
文摘The phenolic acids in free phenolic acid (FPHA), methanol-soluble phenolic ester (MSPE), and methanol-soluble phenolic glycoside (MSPG) fractions of two carob products, natural carob-pod flour (CPF) and commercial carob-pod flour (CCPF), were identified and quantified using high-performance liquid chromatography-mass spectrometry (HPLC-MS). Six phenolic acids were identified in the carob flours (gallic acid, protocatechuic acid, gentisic acid, syringic acid, p- coumaric acid, and sinapic acid). Gallic acid was the major phenolic acid;and its concentrations in CCPF were substantially higher than in CPF (135 - 166 and 85.2 - 91.3 mg/g dw, respectively). The concentrations of p-coumaric acid and sinapic acid were also higher in CCPF than in CPF. In contrast, the concentrations of protocatechuic acid and gentisic acid were generally lower in CCPF than in CPF, with the only exception being gentisic acid glycosides. Both carob-pod flours contained almost the same amount of sinapic acid and syringic acid. The total phenolic contents of the FPHA, MSPE, and MSPG fractions of CPF were found to be 44%, 38%, and 69% that of the respective fractions of CCPF. Correspondingly, the FPHA, MSPE, and MSPG fractions of CCPF had higher free radical-scavenging activity (28.4%, 33.1%, and 26.2%, respectively) than the corresponding fractions of CPF (9.2%, 28.0%, and 9.2%, respectively). Notably, the FPHA and MSPG fractions of each sample had very similar scavenging activity while the MSPE fraction always had higher activity. The FPHA and MSPG fractions of CPF had the lowest activities.
基金supported by the project SEMINE-POR FESR Lazio 2014-2020-Azione 1.2.1-approvato con Determinazione no.G08487 del 19/07/2020-pubblicato sul BURL N.93 del 23/07/2020-modificato con Determinazione no.G10624/2020-pubblicato sul BURL no.116 del 22/09/2020-Italy(to S.S.)the project TowArds Next GENeration Crops,reg.no.CZ.02.01.01/00/22_008/0004581 of the ERDF Programme Johannes Amos Comenius-Czech Republic(to D.T.).
文摘Plants have evolved several strategies to cope with the ever-changing environment.One example of this is given by seed germination,which must occur when environmental conditions are suitable for plant life.In the model system Arabidopsis thaliana seed germination is induced by light;however,in nature,seeds of several plant species can germinate regardless of this stimulus.While the molecular mechanisms underlying light-induced seed germination are well understood,those governing germination in the dark are still vague,mostly due to the lack of suitable model systems.Here,we employ Cardamine hirsuta,a close relative of Ara-bidopsis,as a powerful model system to uncover the molecular mechanisms underlying light-independent germination.By comparing Cardamine and Arabidopsis,we show that maintenance of the pro-germination hormone gibberellin(GA)levels prompt Cardamine seeds to germinate under both dark and light conditions.Using genetic and molecular biology experiments,we show that the Cardamine DOF transcriptional repressor DOF AFFECTING GERMINATION 1(ChDAG1),homologous to the Arabidopsis transcription factor DAG1,is involved in this process functioning to mitigate GA levels by negatively regulating GA biosynthetic genes ChGA3OX1 and ChGA3OX2,independently of light conditions.We also demonstrate that this mechanism is likely conserved in other Brassicaceae species capable of germinating in dark conditions,such as Lepidium sativum and Camelina sativa.Our data support Cardamine as a new model system suitable for studying light-independent germination studies.Exploiting this system,we have also resolved a long-standing question about the mechanisms controlling light-independent germination in plants,opening new frontiers for future research.
文摘A series of reticulated Arabidopsis thaliana mutants were previously described. All mutants show a reticulate leaf pattern, namely green veins on a pale leaf lamina. They have an aberrant mesophyll structure but an intact layer of bundle sheath cells around the veins. Here, we unravel the function of the previously described reticulated EMS-mutant dovl （differential development of vascular associated cells 1）. By positional cloning, we identified the mutated gene, which encodes glutamine phosphoribosyl pyrophosphate aminotransferase 2 （ATase2）, an enzyme catalyzing the first step of purine nucleotide biosynthesis, dovl is allelic to the previously characterized cial-2 mutant that was isolated in a screen for mutants with impaired chloroplast protein import. We show that purine-derived total cytokinins are lowered in clovl and crosses with phytohormone reporter lines revealed differential reporter activity patterns in dovl. Metabolite profiling unraveled that amino acids that are involved in purine biosynthesis are increased in dovl. This study identified the mo- lecular basis of an established mutant line, which has the potential for further investigation of the interaction between metabolism and leaf development.
