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1.
Plant Physiol Biochem ; 167: 619-629, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34479030

RESUMO

Lily is one of the most economically important flowers worldwide due to its elegant appearance and appealing scent, which is mainly composed of monoterpene ocimene, linalool and benzenoids. Sugars are the primary products of plants, with fructose and hexose sugars being the substrate material for most organic compounds and metabolic pathways in plants. Herein, we isolated and functionally characterized hexokinase (LoHXK) and fructokinase (LoFRK) from Lilium 'Siberia' flower, which indicated their potential roles in floral aroma production. Real-time PCR analysis showed that LoHXK and LoFRK were highly expressed in the flower filament. Overexpression and virus-induced gene silencing (VIGS) assays revealed that LoHXK and LoFRK significantly modified the emission of ß-ocimene and linalool contents via regulation of expression of key structural volatile synthesis genes (LoTPS1 and LoTPS3). Under exogenous glucose and fructose application, the volatile contents of ß-ocimene and linalool were increased and the expression levels of key structural genes were upregulated. The emission of ß-ocimene and linalool followed a diurnal circadian rhythm. Determination of carbon fluxes via 13C-labeled glucose and 13C-labeled fructose experiments showed that the mass spectra of ocimene and linalool significantly increased, however, the m/z ratio of ethyl benzoate did not change. Furthermore, yeast two-hybrid (Y2H) and bimolecular fluorescence complementation (BiFC) assays showed that LoFRK interacted with LoMYB1 and LoMYB2 proteins. Together, these results suggest that hexokinase and fructokinase may play significant roles in the regulation of ocimene and linalool biosynthesis in Lilium 'Siberia'.


Assuntos
Frutoquinases , Hexoquinase , Lilium , Odorantes , Flores/enzimologia , Frutoquinases/genética , Regulação da Expressão Gênica de Plantas , Hexoquinase/genética , Lilium/enzimologia , Lilium/genética
2.
BMC Plant Biol ; 21(1): 373, 2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34388969

RESUMO

BACKGROUND: Flowering is an important inflection point in the transformation from vegetative to reproductive growth, and premature bolting severely decreases crop yield and quality. RESULTS: In this study, a stable early-bolting mutant, ebm3, was identified in an ethyl methanesulfonate (EMS)-mutagenized population of a Chinese cabbage doubled haploid (DH) line 'FT'. Compared with 'FT', ebm3 showed early bolting under natural cultivation in autumn, and curled leaves. Genetic analysis showed that the early-bolting phenotype was controlled by a single recessive nuclear gene. Modified MutMap sequencing, genotyping analyses and allelism test provide strong evidence that BrEBM3 (BraA04g017190.3 C), encoding the histone methyltransferase CURLY LEAF (CLF), was the strongly candidate gene of the emb3. A C to T base substitution in the 14th exon of BrEBM3 resulted in an amino acid change (S to F) and the early-bolting phenotype of emb3. The mutation occurred in the SET domain (Suppressor of protein-effect variegation 3-9, Enhancer-of-zeste, Trithorax), which catalyzes site- and state-specific lysine methylation in histones. Tissue-specific expression analysis showed that BrEBM3 was highly expressed in the flower and bud. Promoter activity assay confirmed that BrEBM3 promoter was active in inflorescences. Subcellular localization analysis revealed that BrEBM3 localized in the nucleus. Transcriptomic studies supported that BrEBM3 mutation might repress H3K27me3 deposition and activate expression of the AGAMOUS (AG) and AGAMOUS-like (AGL) loci, resulting in early flowering. CONCLUSIONS: Our study revealed that an EMS-induced early-bolting mutant ebm3 in Chinese cabbage was caused by a nonsynonymous mutation in BraA04g017190.3 C, encoding the histone methyltransferase CLF. These results improve our knowledge of the genetic and genomic resources of bolting and flowering, and may be beneficial to the genetic improvement of Chinese cabbage.


Assuntos
Substituição de Aminoácidos , Brassica rapa/enzimologia , Histona Metiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Aminoácidos/metabolismo , Brassica rapa/genética , Brassica rapa/crescimento & desenvolvimento , Flores/enzimologia , Flores/genética , Flores/crescimento & desenvolvimento , Histona Metiltransferases/química , Histona Metiltransferases/genética , Mutação , Proteínas de Plantas/genética , Transcriptoma
3.
BMC Plant Biol ; 21(1): 376, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399701

RESUMO

BACKGROUND: Glycolytic pathway is common in all plant organs, especially in oxygen-deficient tissues. Phosphofructokinase (PFK) is a rate-limiting enzyme in the glycolytic pathway and catalyses the phosphorylation of fructose-6-phosphate to fructose-1,6-bisphosphate. Cassava (M. esculenta) root is a huge storage organ with low amount of oxygen. However, less is known about the functions of PFK from M. esculenta (MePFK). We conducted a systematic analysis of MePFK genes to explore the function of the MePFK gene family under hypoxic stress. RESULTS: We identified 13 MePFK genes and characterised their sequence structure. The phylogenetic tree divided the 13 genes into two groups: nine were MePFKs and four were pyrophosphate-fructose-6-phosphate phosphotransferase (MePFPs). We confirmed by green fluorescent protein fusion protein expression that MePFK03 and MePFPA1 were localised in the chloroplast and cytoplasm, respectively. The expression profiles of the 13 MePFKs detected by quantitative reverse transcription polymerase chain reaction revealed that MePFK02, MePFK03, MePFPA1, MePFPB1 displayed higher expression in leaves, root and flower. The expression of MePFK03, MePFPA1 and MePFPB1 in tuber root increased gradually with plant growth. We confirmed that hypoxia occurred in the cassava root, and the concentration of oxygen was sharply decreasing from the outside to the inside root. The expression of MePFK03, MePFPA1 and MePFPB1 decreased with the decrease in the oxygen concentration in cassava root. Waterlogging stress treatment showed that the transcript level of PPi-dependent MePFP and MeSuSy were up-regulated remarkably and PPi-dependent glycolysis bypass was promoted. CONCLUSION: A systematic survey of phylogenetic relation, molecular characterisation, chromosomal and subcellular localisation and cis-element prediction of MePFKs were performed in cassava. The expression profiles of MePFKs in different development stages, organs and under waterlogging stress showed that MePFPA1 plays an important role during the growth and development of cassava. Combined with the transcriptional level of MeSuSy, we found that pyrophosphate (PPi)-dependent glycolysis bypass was promoted when cassava was under waterlogging stress. The results would provide insights for further studying the function of MePFKs under hypoxic stress.


Assuntos
Genoma de Planta , Manihot/enzimologia , Manihot/genética , Fosfofrutoquinases/genética , Fosfofrutoquinases/metabolismo , Cloroplastos/enzimologia , Mapeamento Cromossômico , Cromossomos de Plantas , Sequência Conservada , Citoplasma/enzimologia , Éxons , Flores/enzimologia , Íntrons , Família Multigênica , Oxigênio/metabolismo , Filogenia , Folhas de Planta/enzimologia , Raízes de Plantas/enzimologia , Regiões Promotoras Genéticas , Estresse Fisiológico/genética , Transcriptoma
4.
Mol Biol Rep ; 48(4): 3451-3461, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33934248

RESUMO

Saffron is a well-known Chinese traditional herb, and crocin biosynthesis is related to the yield and quality of saffron. This study aimed to screen differentially expressed genes (DEGs) in saffron at different flowering stages and identify cytochrome P450 (CYP) genes involved in crocin biosynthesis. Saffron samples at different flowering stages were used for RNA sequencing, and DEGs between the samples at three days before the flowering stage (- 3da) and two days after the flowering stage (+ 2da) were screened. Thereafter, significantly differentially expressed CYP genes were identified, and CYP gene expression at different flowering stages and in various tissues of saffron was determined using real-time quantitative polymerase chain reaction (RT-qPCR). After sequencing and analysis, 1508 DEGs between the samples at - 3da and + 2da were identified, including 487 upregulated and 1021 downregulated genes, which were enriched in 16 biological processes, 5 cellular components, 3 molecular functions, and 11 KEGG pathways, including protein processing in endoplasmic reticulum, pentose and glucuronate interconversions, starch and sucrose metabolism, estrogen signaling pathway, and mitogen-activated protein kinase signaling pathway. In addition, 12 significantly differentially expressed CYP genes were identified. The RT-qPCR results showed that CYP76C4, CYP72A15, CYP72A219, CYP97B2, CYP714C2, CYP71A1, CYP94C1, and CYP86A8 were all expressed in the pistils, and CYP72A219, CYP72A15, CYP97B2, CYP71A1, and CYP86A8 were highly expressed in the pistils. Our study established a transcriptome library of saffron and found that CYP72A219, CYP72A15, CYP97B2, CYP71A1, and CYP86A8 may be candidates involved crocin biosynthesis in saffron.


Assuntos
Carotenoides/metabolismo , Crocus/enzimologia , Sistema Enzimático do Citocromo P-450/metabolismo , Flores/enzimologia , Regulação da Expressão Gênica de Plantas , Crocus/genética , Sistema Enzimático do Citocromo P-450/genética , Flores/genética , Perfilação da Expressão Gênica , Redes e Vias Metabólicas , Análise de Sequência de RNA , Transdução de Sinais
5.
Plant Cell ; 33(2): 306-321, 2021 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-33793793

RESUMO

Unisexual flowers provide a useful system for studying plant sex determination. In cucumber (Cucumis sativus L.), three major Mendelian loci control unisexual flower development, Female (F), androecious [a; 1-aminocyclopropane-1-carboxylate {ACC} synthase 11, acs11], and Monoecious (M; ACS2), referred to here as the Female, Androecious, Monoecious (FAM) model, in combination with two genes, gynoecious (g, the WIP family C2H2 zinc finger transcription factor gene WIP1) and the ethylene biosynthetic gene ACC oxidase 2 (ACO2). The F locus, conferring gynoecy and the potential for increasing fruit yield, is defined by a 30.2-kb tandem duplication containing three genes. However, the gene that determines the Female phenotype, and its mechanism, remains unknown. Here, we created a set of mutants and revealed that ACS1G is responsible for gynoecy conferred by the F locus. The duplication resulted in ACS1G acquiring a new promoter and expression pattern; in plants carrying the F locus duplication, ACS1G is expressed early in floral bud development, where it functions with ACO2 to generate an ethylene burst. The resulting ethylene represses WIP1 and activates ACS2 to initiate gynoecy. This early ACS1G expression bypasses the need for ACS11 to produce ethylene, thereby establishing a dominant pathway for female floral development. Based on these findings, we propose a model for how these ethylene biosynthesis genes cooperate to control unisexual flower development in cucumber.


Assuntos
Cucumis sativus/enzimologia , Cucumis sativus/genética , Flores/enzimologia , Flores/genética , Liases/genética , Sequência de Aminoácidos , Regulação da Expressão Gênica de Plantas , Loci Gênicos , Genoma de Planta , Genótipo , Glucuronidase/metabolismo , Liases/química , Fenótipo , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
6.
Plant Sci ; 305: 110835, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33691969

RESUMO

Anthocyanins are important flavonoid pigments in plants. Malonyl CoA is an important intermediate in anthocyanin synthesis, and citrate, formed by citrate synthase (CS) catalysing oxaloacetate, is the precursor for the formation of malonyl-CoA. CS is composed of two isoforms, mitochondrial citrate synthase (mCS), a key enzyme of the tricarboxylic acid (TCA) cycle, and citrate synthase (CSY) localizated in microbodies in plants. However, no CS isoform involvement in anthocyanin synthesis has been reported. In this study, we identified the entire CS family in petunia (Petunia hybrida): PhmCS, PhCSY1 and PhCSY2. We obtained petunia plants silenced for the three genes. PhmCS silencing resulted in abnormal development of leaves and flowers. The contents of citrate and anthocyanins were significantly reduced in flowers in PhmCS-silenced plants. However, silencing of PhCSY1 and/or PhCSY2 did not cause a visible phenotype change in petunia. These results showed that PhmCS is involved in anthocyanin synthesis and the development of leaves and flowers, and that the citrate involved in anthocyanin synthesis mainly derived from mitochondria rather than microbodies in petunia.


Assuntos
Antocianinas/biossíntese , Antocianinas/genética , Citrato (si)-Sintase/genética , Citrato (si)-Sintase/metabolismo , Flores/enzimologia , Flores/genética , Petunia/enzimologia , Petunia/genética , Regulação da Expressão Gênica de Plantas , Genes Mitocondriais
7.
Food Chem ; 345: 128741, 2021 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-33601650

RESUMO

Bovine whey protein was hydrolysed using cardosins A and B purified from dried flowers of Cynara cardunculus by combining diafiltration, anion-exchange chromatography and ultrafiltration. The proteolysis experiments were performed using different whey protein concentrations and enzyme/substrate (E/S) ratios. Complete hydrolysis of the main whey proteins, ß-Lactoglobulin (ß-Lg) and α-lactalbumin (α-La), was achieved after 4 h, at E/S ratios of 1/150 U/mg, regardless the initial protein concentration. In previous reports, the authors suggested that cardosins could not hydrolyse ß-lactoblogulin. However, our promising results open up new possibilities to further explore the action of cardosins on whey proteins for the production of bioactive peptides.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Cynara/enzimologia , Lactoglobulinas/metabolismo , Proteínas de Plantas/metabolismo , Animais , Antioxidantes/metabolismo , Ácido Aspártico Endopeptidases/isolamento & purificação , Bovinos , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Flores/enzimologia , Flores/metabolismo , Hidrólise , Lactalbumina/metabolismo , Lactoglobulinas/análise , Proteínas de Plantas/isolamento & purificação , Especificidade por Substrato
8.
Plant Cell Rep ; 40(2): 361-374, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33392730

RESUMO

KEY MESSAGE: MANNANASE7 gene in Brassica napus L. encodes a hemicellulose which located at cell wall or extracellular space and dehiscence-resistance can be manipulated by altering the expression of MANNANASE7. Silique dehiscence is an important physiological process in plant reproductive development, but causes heavy yield loss in crops. The lack of dehiscence-resistant germplasm limits the application of mechanized harvesting and greatly restricts the rapeseed (Brassica napus L.) production. Hemicellulases, together with cellulases and pectinases, play important roles in fruit development and maturation. The hemicellulase gene MANNANASE7 (MAN7) was previously shown to be involved in the development and dehiscence of Arabidopsis (Arabidopsis thaliana) siliques. Here, we cloned BnaA07g12590D (BnMAN7A07), an AtMAN7 homolog from rapeseed, and demonstrate its function in the dehiscence of rapeseed siliques. We found that BnMAN7A07 was expressed in both vegetative and reproductive organs and significantly highly expressed in leaves, flowers and siliques where the abscission or dehiscence process occurs. Subcellular localization experiment showed that BnMAN7A07 was localized in the cell wall. The biological activity of the BnMAN7A07 protein isolated and purified through prokaryotic expression system was verified to catalyse the decomposition of xylan into xylose. Phenotypic studies of RNA interference (RNAi) lines revealed that down-regulation of BnMAN7A07 in rapeseed could significantly enhance silique dehiscence-resistance. In addition, the expression of upstream silique development regulators is altered in BnMAN7A07-RNAi plants, suggesting that a possible feedback regulation mechanism exists in the regulation network of silique dehiscence. Our results demonstrate that dehiscence-resistance can be manipulated by altering the expression of hemicellulase gene BnMAN7A07, which could provide an available genetic resource for breeding practice in rapeseed which is beneficial to mechanized harvest.


Assuntos
Brassica napus/enzimologia , Glicosídeo Hidrolases/metabolismo , Polissacarídeos/metabolismo , Arabidopsis/enzimologia , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica napus/genética , Parede Celular/enzimologia , Regulação para Baixo , Espaço Extracelular/enzimologia , Flores/enzimologia , Flores/genética , Regulação da Expressão Gênica de Plantas , Glicosídeo Hidrolases/genética , Manosidases/genética , Manosidases/metabolismo , Melhoramento Vegetal , Folhas de Planta/enzimologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
9.
Biomolecules ; 11(2)2021 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-33503885

RESUMO

Lipoxygenases are widespread enzymes that catalyze oxidation of polyunsaturated fatty acids (linoleic, linolenic, and arachidonic acid) to produce hydroperoxides. Lipoxygenase reactions can be desirable, but also lipoxygenases can react in undesirable ways. Most of the products of lipoxygenase reactions are aromatic compounds that can affect food properties, especially during long-term storage. Lipoxygenase action on unsaturated fatty acids could result in off-flavor/off-odor development, causing food spoilage. In addition, lipoxygenases are present in the human body and play an important role in stimulation of inflammatory reactions. Inflammation is linked to many diseases, such as cancer, stroke, and cardiovascular and neurodegenerative diseases. This review summarized recent research on plant families and species that can inhibit lipoxygenase activity.


Assuntos
Ácidos Graxos Insaturados/química , Inflamação/tratamento farmacológico , Inibidores de Lipoxigenase/farmacologia , Oxigênio/química , Extratos Vegetais/farmacologia , Animais , Araquidonato 15-Lipoxigenase/biossíntese , Araquidonato 5-Lipoxigenase/biossíntese , Ácido Araquidônico , Ácidos Graxos , Flores/enzimologia , Humanos , Peróxido de Hidrogênio/química , Concentração Inibidora 50 , Lipoxigenase/metabolismo , Inibidores de Lipoxigenase/química , Oxirredução , Folhas de Planta/enzimologia , Polifenóis/química
10.
Int J Mol Sci ; 21(22)2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33202940

RESUMO

In addition to the well-known diterpenoid steviol glycosides, Stevia rebaudiana (Stevia) produces many labdane-type diterpenoids and a wide range of mono- and sesquiterpenoids. However, biosynthesis of mono- and sesquiterpenoids in Stevia remains unknown. Here we analyzed the extracts of Stevia leaves, flowers, stems, and roots by Gas Chromatography-Mass Spectrometry and putatively identified a total of 69 volatile organic compounds, most of which were terpenoids with considerably varied quantities among the four tissues of Stevia. Using Stevia transcriptomes, we identified and functionally characterized five terpene synthases (TPSs) that produced major mono- and sesquiterpenoids in Stevia. Transcript levels of these Stevia TPSs and levels of corresponding terpenoids correlated well in Stevia tissues. Particularly, the root-specific SrTPS4 and SrTPS5 catalyzed the formation of γ-curcumene/zingiberene/ß-sesquiphellandrene and α-longipinene/ß-himachalene/himachalol as multifunctional sesqui-TPSs, respectively. Most of the SrTPSs were highly responsive to various environmental stresses in a tissue-specific manner. Taken together, our results provide new insights into how Stevia produces diverse terpenoids to confer differential responses to various environmental factors in each tissue.


Assuntos
Alquil e Aril Transferases/biossíntese , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/biossíntese , Stevia/enzimologia , Alquil e Aril Transferases/genética , Flores/enzimologia , Flores/genética , Folhas de Planta/enzimologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Raízes de Plantas/enzimologia , Raízes de Plantas/genética , Stevia/genética , Terpenos/metabolismo
11.
Int J Mol Sci ; 21(19)2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32977586

RESUMO

Floral scent is a key ornamental trait that determines the quality and commercial value of orchids. Geraniol, an important volatile monoterpene in orchids that attracts pollinators, is also involved in responses to stresses but the geraniol synthase (GES) responsible for its synthesis in the medicinal orchid Dendrobium officinale has not yet been identified. In this study, three potential geraniol synthases were mined from the D. officinale genome. DoGES1, which was localized in chloroplasts, was characterized as a geraniol synthase. DoGES1 was highly expressed in flowers, especially in petals. DoGES1 transcript levels were high in the budding stage of D. officinale flowers at 11:00 a.m. DoGES1 catalyzed geraniol in vitro, and transient expression of DoGES1 in Nicotiana benthamiana leaves resulted in the accumulation of geraniol in vivo. These findings on DoGES1 advance our understanding of geraniol biosynthesis in orchids, and lay the basis for genetic modification of floral scent in D. officinale or in other ornamental orchids.


Assuntos
Proteínas de Cloroplastos , Cloroplastos , Dendrobium , Flores , Odorantes , Monoéster Fosfórico Hidrolases , Proteínas de Cloroplastos/genética , Proteínas de Cloroplastos/metabolismo , Cloroplastos/enzimologia , Cloroplastos/genética , Dendrobium/enzimologia , Dendrobium/genética , Flores/enzimologia , Flores/genética , Monoéster Fosfórico Hidrolases/genética , Monoéster Fosfórico Hidrolases/metabolismo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Tabaco/enzimologia , Tabaco/genética
12.
Plant J ; 104(4): 932-949, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32808386

RESUMO

Brassica napus is currently cultivated as an important ornamental crop in China. Flower color has attracted much attention in rapeseed genetics and breeding. Here, we characterize an orange-flowered mutant of B. napus that exhibits an altered carotenoid profile in its petals. As revealed by map-based cloning, the change in color from yellow to orange is attributed to the loss of BnaC09.ZEP (zeaxanthin epoxidase) and a 1695-bp deletion in BnaA09.ZEP. HPLC analysis, genetic complementation and CRISPR/Cas9 experiments demonstrated that BnaA09.ZEP and BnaC09.ZEP have similar functions, and the abolishment of both genes led to a substantial increase in lutein content and a sharp decline in violaxanthin content in petals but not leaves. BnaA09.ZEP and BnaC09.ZEP are predominantly expressed in floral tissues, whereas their homologs, BnaA07.ZEP and BnaC07.ZEP, mainly function in leaves, indicating redundancy and tissue-specific diversification of BnaZEP function. Transcriptome analysis in petals revealed differences in the expression of carotenoid and flavonoid biosynthesis-related genes between the mutant and its complementary lines. Flavonoid profiles in the petals of complementary lines were greatly altered compared to the mutant, indicating potential cross-talk between the regulatory networks underlying the carotenoid and flavonoid pathways. Additionally, our results indicate that there is functional compensation by BnaA07.ZEP and BnaC07.ZEP in the absence of BnaA09.ZEP and BnaC09.ZEP. Cloning and characterization of BnaZEPs provide insights into the molecular mechanisms underlying flower pigmentation in B. napus and would facilitate breeding of B. napus varieties with higher ornamental value.


Assuntos
Brassica napus/genética , Carotenoides/metabolismo , Regulação da Expressão Gênica de Plantas , Oxirredutases/metabolismo , Brassica napus/enzimologia , Brassica napus/fisiologia , Sistemas CRISPR-Cas , Flavonoides/metabolismo , Flores/enzimologia , Flores/genética , Flores/fisiologia , Inativação Gênica , Luteína/metabolismo , Oxirredutases/genética , Pigmentação/genética , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Xantofilas/metabolismo
13.
J Plant Physiol ; 252: 153245, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32750644

RESUMO

Volatile benzenoids/phenylpropanoids are characteristic scent compounds in petunia flowers and are reported to be stored as glycosides in the vacuoles of petal cells. Here, we used transcriptomics and co-expression approaches with volatile benzenoid/phenylpropanoid biosynthetic genes to identify three petunia genes (UGT85A96, UGT85A97, and UGT85A98) encoding UDP-glycosyltransferase. The analyses of spatiotemporal gene expression revealed that all UGT85 genes were highly expressed in floral tissues such as petals and pistils. Functional characterization of recombinant UGT85A96 and UGT85A98 proteins expressed in Escherichia coli showed that UGT85A98 could transfer a glucosyl moiety from UDP-glucose to the hydroxyl group of various substrates including volatile benzenoids/phenylpropanoids, terpene alcohol, flavonoids, and C6 alcohol, whereas UGT85A96 specifically catalyzes the glucosylation of 2-phenylethanol and benzyl alcohol. This report describes the first experimental evidence to identify UGT enzymes that catalyze the glycosylation of volatile benzenoids/phenylpropanoids in petunia flowers.


Assuntos
Glucosiltransferases/metabolismo , Petunia/enzimologia , Uridina Difosfato Glucose/química , Clonagem Molecular , Flores/enzimologia
14.
Plant Sci ; 297: 110529, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32563467

RESUMO

The aerial parts of apple are protected against environmental stress by cuticular wax. Although it has been suggested that several long-chain acyl-CoA synthetases are involved in wax biosynthesis, the molecular pathway of apple cuticular wax biosynthesis remains unclear. In this study, an MdLACS4 protein with long-chain acyl-CoA synthetase activity was isolated from apple. The MdLACS4 gene was highly expressed in pericarp, stem, and mature leaf tissues. Ectopic expression of MdLACS4 in Arabidopsis induced early flowering. Compared with wild-type plants, MdLACS4 transgenic Arabidopsis exhibited lower water loss rates, reduced epidermal permeability, increased cuticular wax in stems and leaves, and altered cuticular ultrastructure. Furthermore, the accumulation of cuticular wax enhanced the resistance of MdLACS4 transgenic plants to drought and salt stress. Finally, predicted protein functional interaction networks for LACS4 suggested that the molecular regulation pathway of MdLACS4 mediates wax biosynthesis in apple.


Assuntos
Coenzima A Ligases/fisiologia , Flores/crescimento & desenvolvimento , Malus/enzimologia , Proteínas de Plantas/fisiologia , Arabidopsis/enzimologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Coenzima A Ligases/genética , Sequência Conservada/genética , Flores/enzimologia , Cromatografia Gasosa-Espectrometria de Massas , Genes de Plantas/genética , Genes de Plantas/fisiologia , Liases/genética , Liases/fisiologia , Malus/genética , Microscopia Eletrônica de Varredura , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Estresse Fisiológico
15.
Planta ; 251(5): 98, 2020 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-32306103

RESUMO

MAIN CONCLUSION: This work reveals information about new peroxisomal targeting signals type 1 and identifies trehalose-6-phosphate phosphatase I as multitargeted and is implicated in plant development, reproduction, and stress response. A putative, non-canonical peroxisomal targeting signal type 1 (PTS1) Pro-Arg-Met > was identified in the extreme C-terminus of trehalose-6-phosphate phosphatase (TPP)I. TPP catalyzes the final step of trehalose synthesis, and the enzyme was previously characterized to be nuclear only (Krasensky et al. in Antioxid Redox Signal 21(9):1289-1304, 2014). Here we show that the TPPI C-terminal decapeptide ending with Pro-Arg-Met > or Pro-Lys-Met > can indeed function as a PTS1. Upon transient expression in two plant expression systems, the free C- or N-terminal end led to the full-length TPPI targeting to peroxisomes and plastids, respectively. The nucleus and nucleolus targeting of the full-length TPPI was observed in both cases. The homozygous T-DNA insertion line of TPPI showed a pleiotropic phenotype including smaller leaves, shorter roots, delayed flowering, hypersensitivity to salt, and a sucrose dependent seedling development. Our results identify novel PTS1s, and TPPI as a protein multi-targeted to peroxisomes, plastids, nucleus, and nucleolus. Altogether our findings implicate an essential role for TPPI in development, reproduction, and cell signaling.


Assuntos
Arabidopsis/enzimologia , Flores/enzimologia , Sinais de Orientação para Peroxissomos , Monoéster Fosfórico Hidrolases/metabolismo , Transdução de Sinais , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/fisiologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Núcleo Celular/metabolismo , Biologia Computacional , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Peroxissomos/enzimologia , Monoéster Fosfórico Hidrolases/genética , Filogenia , Plastídeos/metabolismo , Reprodução
16.
J Agric Food Chem ; 68(10): 3214-3219, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32079394

RESUMO

Four terpene synthases for the biosynthesis of volatile terpenoids were identified from the transcriptome of Stellera chamaejasme L. flowers, including SchTPS1, SchTPS2, SchTPS3, and SchTPS4. Their functions were characterized by synthetic biology approaches in Escherichia coli and in vitro enzymatic assays. SchTPS1, SchTPS2, and SchTPS3 are guaiene synthases, while SchTPS4 is an (E,E)-geranyl linalool synthase. Next, SchTPS1 and α-guaiene 2-oxidase VvSTO2 were co-expressed in Saccharomyces cerevisiae to reconstruct the biosynthetic pathway of (-)-rotundone, which is a unique aroma compound in fruits, vegetables, and wines. This is the first report for the construction of a (-)-rotundone-producing microbial platform.


Assuntos
Alquil e Aril Transferases/metabolismo , Azulenos/metabolismo , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Sesquiterpenos de Guaiano/metabolismo , Sesquiterpenos/metabolismo , Thymelaeaceae/enzimologia , Alquil e Aril Transferases/genética , Vias Biossintéticas , Flores/enzimologia , Flores/genética , Expressão Gênica , Proteínas de Plantas/genética , Saccharomyces cerevisiae/genética , Thymelaeaceae/genética
17.
Sci Rep ; 10(1): 1299, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31992834

RESUMO

The majority of carotenoids in petals are xanthophylls and most of these xanthophylls are esterified with fatty acids. Although petunia (Petunia x hybrida) is an important ornamental plant, it cannot accumulate enough carotenoids to have deep-yellow flowers. Our previous study suggested that low esterification activity causes low carotenoid accumulation in petunia corollas. Here, we introduced xanthophyll esterase (XES) from the petals of Ipomoea obscura, tomato (Solanum lycopersicum), and marigold (Tagetes erecta) into a pale-yellow-flowered cultivar of petunia to see whether these affect carotenoid accumulation in petunia corollas. Carotenoid contents and the proportions of esterified xanthophylls were elevated in the corollas of XES-overexpressing (XES-OX) transformants. Expression analysis showed that the transcript levels of endogenous carotenoid biosynthetic genes, which included geranylgeranyl diphosphate synthase 2, ζ-carotene desaturase, and lycopene ß-ring cyclase in corolla tubes were upregulated in XES-OX plants. In addition, we discovered a difference in the composition of esterified xanthophylls among XES-OX plants, which may be caused by differences in the substrate specificity of their respective XESs. We conclude that esterification is an important process for carotenoid accumulation and XES is a useful tool for the quantitative and qualitative control of carotenoid accumulation in petals.


Assuntos
Esterases , Flores , Expressão Gênica , Petunia , Pigmentação , Proteínas de Plantas , Plantas Geneticamente Modificadas , Xantofilas/metabolismo , Esterases/biossíntese , Esterases/genética , Flores/enzimologia , Flores/genética , Petunia/enzimologia , Petunia/genética , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética
18.
Sci Rep ; 10(1): 933, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31969641

RESUMO

For a better understanding terpenoid volatile production in Camellia sinensis, global terpenoid synthase gene (TPS) transcription analysis was conducted based on transcriptomic data combined with terpenoid metabolic profiling under different abiotic stress conditions. Totally 80 TPS-like genes were identified. Twenty-three CsTPS genes possessed a complete coding sequence and most likely were functional. The remaining 57 in the currently available database lack essential gene structure or full-length transcripts. Distinct tempo-spatial expression patterns of CsTPS genes were found in tea plants. 17 genes were substantially expressed in all the tested organs with a few exceptions. The other 17 were predominantly expressed in leaves whereas additional eight were primarily expressed in flowers. Under the treatments of cold acclimation, salt and polyethylene glycol, CsTPS67, -69 and -71 were all suppressed and the inhibited expression of many others were found in multiple stress treatments. However, methyl jasmonate resulted in the enhanced expression of the majority of CsTPS genes. These transcription data were largely validated using qPCR. Moreover, volatile terpenoid profiling with leaves, flowers and stress-treated plants revealed a general association between the abundances of mono- and sesqui-terpenoids and some CsTPS genes. These results provide vital information for future studies on CsTPS regulation of terpenoid biosynthesis.


Assuntos
Alquil e Aril Transferases/genética , Camellia sinensis/enzimologia , Camellia sinensis/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica/genética , Estresse Fisiológico/genética , Terpenos/metabolismo , Aclimatação/genética , Acetatos , Camellia sinensis/metabolismo , Temperatura Baixa , Ciclopentanos , Flores/enzimologia , Flores/genética , Flores/metabolismo , Oxilipinas , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Transcrição Genética/genética , Transcriptoma/genética
19.
Plant Mol Biol ; 102(4-5): 517-535, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31927660

RESUMO

KEY MESSAGE: We reported the functional characterization of cDNAs encoding short-chain isoprenyl diphosphate synthases that control the partitioning of precursors for lavender terpenoids. Lavender essential oil is composed of regular and irregular monoterpenes, which are derived from linear precursors geranyl diphosphate (GPP) and lavandulyl diphosphate (LPP), respectively. Although this plant strongly expresses genes responsible for the biosynthesis of both monoterpene classes, it is unclear why regular monoterpenes dominate the oil. Here, we cloned and characterized Lavandula x intermedia cDNAs encoding geranyl diphosphate synthase (LiGPPS), geranylgeranyl diphosphate synthase (LiGGPPS) and farnesyl diphosphate synthase (LiFPPS). LiGPPS was heteromeric protein, consisting of a large subunit (LiGPPS.LSU) and a small subunit for which two different cDNAs (LiGPPS.SSU1 and LiGPPS.SSU2) were detected. Neither recombinant LiGPPS subunits was active by itself. However, when co-expressed in E. coli LiGPPS.LSU and LiGPPS.SSU1 formed an active heteromeric GPPS, while LiGPPS.LSU and LiGPPS.SSU2 did not form an active protein. Recombinant LiGGPPS, LiFPPS and LPP synthase (LPPS) proteins were active individually. Further, LiGPPS.SSU1 modified the activity of LiGGPPS (to produce GPP) in bacterial cells co-expressing both proteins. Given this, and previous evidence indicating that GPPS.SSU can modify the activity of GGPPS to GPPS in vitro and in plants, we hypothesized that LiGPPS.SSU1 modifies the activity of L. x intermedia LPP synthase (LiLPPS), thus accounting for the relatively low abundance of LPP-derived irregular monoterpenes in this plant. However, LiGPPS.SSU1 did not affect the activity of LiLPPS. These results, coupled to the observation that LiLPPS transcripts are more abundant than those of GPPS subunits in L. x intermedia flowers, suggest that regulatory mechanisms other than transcriptional control of LPPS regulate precursor partitioning in lavender flowers.


Assuntos
Alquil e Aril Transferases/metabolismo , Dimetilaliltranstransferase/metabolismo , Flores/enzimologia , Lavandula/enzimologia , Proteínas de Plantas/metabolismo , Alquil e Aril Transferases/genética , Catálise , Dimetilaliltranstransferase/genética , Difosfatos , Diterpenos , Escherichia coli/genética , Escherichia coli/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Teste de Complementação Genética , Lavandula/genética , Monoterpenos/metabolismo , Fases de Leitura Aberta , Fenótipo , Filogenia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Terpenos/metabolismo , Tabaco/metabolismo
20.
Pak J Biol Sci ; 23(3): 264-270, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31944087

RESUMO

BACKGROUND AND OBJECTIVE: Flavonols in plants are catalyzed by flavonol synthase (FLS) enzyme. FLS was reported expressed in flowers and fruits, i.e., Dianthus caryophyllus L. (Caryophyllaceae), Petunia hybrida Hort. (Solanaceae), Arabidopsis thaliana L. (Brassicaceae), Citrus unshiu Marc. (Rutaceae). However, none reported about FLS in medicinal plants, particularly those which possess anti-inflammatory activity. This study was aimed to extract and identify FLS in the rhizome of Boesenbergia rotunda (Zingiberaceae) and to determine quercetin in the ethanol extract of the rhizome. MATERIALS AND METHODS: The protein extraction of the rhizome was carried out by employing Laing and Christeller's (2004) and Wang's (2014) methods. The extracted-proteins were separated by using SDS-PAGE, followed by the measurement of FLS intensity by using Gel Analyzer. The FLS-1 of recombinant A. thaliana was employed as the standard. The determination of quercetin in the rhizome was carried out using LC-MS. RESULTS: The FLS occurred as a thick band at 38 kDa with intensity 116-158. The LC chromatogram of the extract indicated a small peak at 7.94 min similar to that of quercetin standard. The MS spectra at 7.94 min indicated that quercetin is present in the B. rotunda rhizome (m/z = 303.0549). The concentration of quercetin in the extract is 0.022% w/v. CONCLUSION: The FLS, an enzyme which plays an important role in producing quercetin, was detected in B. rotunda rhizome planted in Indonesia. As a consequence, quercetin in a small amount, was also quantified in the rhizome of this plant. This report will add a scientific insight of B. rotunda for biological sciences.


Assuntos
Flores/enzimologia , Frutas/enzimologia , Oxirredutases/química , Proteínas de Plantas/química , Quercetina/biossíntese , Zingiberaceae/enzimologia , Arabidopsis/enzimologia , Citrus/enzimologia , Dianthus/enzimologia , Etanol , Flavonóis/química , Indonésia , Petunia/enzimologia , Extratos Vegetais , Plantas Medicinais/enzimologia , Rizoma/enzimologia
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