RESUMEN

BACKGROUND: Terpenes are important components of plant aromas, and terpene synthases (TPSs) are the key enzymes driving terpene diversification. In this study, we characterized the volatile terpenes in five different Chrysanthemum nankingense tissues. In addition, genome-wide identification and expression analysis of TPS genes was conducted utilizing an improved chromosome-scale genome assembly and tissue-specific transcriptomes. The biochemical functions of three representative TPSs were also investigated. RESULTS: We identified tissue-specific volatile organic compound (VOC) and volatile terpene profiles. The improved Chrysanthemum nankingense genome assembly was high-quality, including a larger assembled size (3.26 Gb) and a better contig N50 length (3.18 Mb) compared to the old version. A total of 140 CnTPS genes were identified, with the majority representing the TPS-a and TPS-b subfamilies. The chromosomal distribution of these TPS genes was uneven, and 26 genes were included in biosynthetic gene clusters. Closely-related Chrysanthemum taxa were also found to contain diverse TPS genes, and the expression profiles of most CnTPSs were tissue-specific. The three investigated CnTPS enzymes exhibited versatile activities, suggesting multifunctionality. CONCLUSIONS: We systematically characterized the structure and diversity of TPS genes across the Chrysanthemum nankingense genome, as well as the potential biochemical functions of representative genes. Our results provide a basis for future studies of terpene biosynthesis in chrysanthemums, as well as for the breeding of improved chrysanthemum varieties.

Asunto(s)

Transferasas Alquil y Aril , Chrysanthemum , Genoma de Planta , Familia de Multigenes , Terpenos , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo , Chrysanthemum/genética , Chrysanthemum/enzimología , Terpenos/metabolismo , Filogenia , Compuestos Orgánicos Volátiles/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma

RESUMEN

Acacetin, a flavonoid compound, possesses a wide range of pharmacological effects, including antimicrobial, immune regulation, and anticancer effects. Some key steps in its biosynthetic pathway were largely unknown in flowering plants. Here, we present the first haplotype-resolved genome of Chrysanthemum indicum, whose dried flowers contain abundant flavonoids and have been utilized as traditional Chinese medicine. Various phylogenetic analyses revealed almost equal proportion of three tree topologies among three Chrysanthemum species (C. indicum, C. nankingense, and C. lavandulifolium), indicating that frequent gene flow among Chrysanthemum species or incomplete lineage sorting due to rapid speciation might contribute to conflict topologies. The expanded gene families in C. indicum were associated with oxidative functions. Through comprehensive candidate gene screening, we identified five flavonoid O-methyltransferase (FOMT) candidates, which were highly expressed in flowers and whose expressional levels were significantly correlated with the content of acacetin. Further experiments validated two FOMTs (CI02A009970 and CI03A006662) were capable of catalyzing the conversion of apigenin into acacetin, and these two genes are possibly responsible acacetin accumulation in disc florets and young leaves, respectively. Furthermore, combined analyses of ancestral chromosome reconstruction and phylogenetic trees revealed the distinct evolutionary fates of the two validated FOMT genes. Our study provides new insights into the biosynthetic pathway of flavonoid compounds in the Asteraceae family and offers a model for tracing the origin and evolutionary routes of single genes. These findings will facilitate in vitro biosynthetic production of flavonoid compounds through cellular and metabolic engineering and expedite molecular breeding of C. indicum cultivars.

Asunto(s)

Chrysanthemum , Evolución Molecular , Flavonas , Genoma de Planta , Filogenia , Proteínas de Plantas , Chrysanthemum/genética , Chrysanthemum/metabolismo , Chrysanthemum/enzimología , Flavonas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta/genética , Haplotipos , Diploidia , Flavonoides/metabolismo , Flavonoides/biosíntesis , Flores/genética , Flores/enzimología , Flores/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo

RESUMEN

As the most prominent proton pumps in plants, vacuolar H+-ATPases (VHAs) comprise multiple subunits that are important for physiological processes and stress tolerance in plants. However, few studies on the roles of subunit genes of VHAs in chrysanthemum have been reported to date. In this study, the gene of A subunit of V-ATPase in chrysanthemum (CmVHA-A) was cloned and identified. CmVHA-A was conserved with VHA-A proteins from other plants. Expression analysis showed that CmVHA-A was highly expressed in most tissues of chrysanthemum except for the flower bud, and was readily induced by polyethylene glycol (PEG) treatment. Functional analysis demonstrated that CmVHA-A exerted a negative influence on the growth and development of shoot and root of chrysanthemum under normal conditions. RNA-sequencing (RNA-seq) analysis revealed the possible explanations for phenotypic differences between transgenic and wild-type (WT) plants. Under drought conditions, CmVHA-A positively affected the drought tolerance of chrysanthemum by enhancing antioxidase activity and alleviating photosynthetic disruption. Overall, CmVHA-A plays opposite roles in plant growth and drought tolerance of chrysanthemums under different growing conditions.

Asunto(s)

Chrysanthemum , Proteínas de Plantas , ATPasas de Translocación de Protón Vacuolares , Chrysanthemum/genética , Chrysanthemum/fisiología , Chrysanthemum/crecimiento & desarrollo , Chrysanthemum/enzimología , ATPasas de Translocación de Protón Vacuolares/genética , ATPasas de Translocación de Protón Vacuolares/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sequías , Regulación de la Expresión Génica de las Plantas , Filogenia , Plantas Modificadas Genéticamente/genética , Estrés Fisiológico/genética , Resistencia a la Sequía

RESUMEN

Male sterility, as a common reproductive characteristic in plants, plays an important role in breeding, in which pollen abortion is a key factor leading to male sterility. Here, based on a low expression level gene CmACOS5 in transcriptome of pollen abortive chrysanthemum, a new transcription factor CmLBD2 of the Lateral Organ Boundaries Domain family, which could bind the promoter of CmACOS5 by yeast one-hybrid library was screened. This study revealed the origin and expression pattern of CmLBD2 in chrysanthemum and verified the functions of two genes in pollen development by transgenic means. Inhibiting the expression of CmACOS5 or CmLBD2 can lead to a large reduction in pollen and even abortion in chrysanthemum. Using yeast one-/two-hybrid, electrophoretic mobility shift assays, and luciferase reporter assays, it was verified that CmLBD2 directly binds to the promoter of CmACOS5. These results suggest that LBD2 is a novel, key transcription factor regulating pollen development. This result will provide a new research background for enriching the function of LBD family proteins and also lay a new foundation for the breeding of male sterile lines and the mechanism of pollen development.

Asunto(s)

Chrysanthemum/crecimiento & desarrollo , Chrysanthemum/genética , Coenzima A Ligasas/genética , Proteínas de Plantas/genética , Polen/crecimiento & desarrollo , Factores de Transcripción/genética , Chrysanthemum/enzimología , Chrysanthemum/metabolismo , Coenzima A Ligasas/metabolismo , Proteínas de Plantas/metabolismo , Polen/genética , Factores de Transcripción/metabolismo

RESUMEN

Chrysanthemum (Chrysanthemum morifolium (Ramat.) Kitamura) plants have great ornamental value, but their flowers can also be a source of pollen contamination. Previously, morphological and cytological studies have shown that anthers of some chrysanthemum cultivars such as 'Qx-115' fail to dehisce, although the underlying mechanism is largely unknown. In this study, we investigated the molecular basis of anther indehiscence in chrysanthemum via transcriptome analysis of a dehiscent cultivar ('Qx-097') and an indehiscent cultivar ('Qx-115'). We also measured related physiological indicators during and preceding the period of anther dehiscence. Our results showed a difference in pectinase accumulation and activity between the two cultivars during dehiscence. Detection of de-esterified pectin and highly esterified pectin in anthers during the period preceding anther dehiscence using LM19 and LM20 monoclonal antibodies showed that both forms of pectin were absent in the stomium region of 'Qx-097' anthers but were abundant in that of 'Qx-115' anthers. Analysis of transcriptome data revealed a significant difference in the expression levels of two transcription factor-encoding genes, CmLOB27 and CmERF72, between 'Qx-097' and 'Qx-115' during anther development. Transient overexpression of CmLOB27 and CmERF72 separately in tobacco leaves promoted pectinase biosynthesis. We conclude that CmLOB27 and CmERF72 are involved in the synthesis of pectinase, which promotes the degradation of pectin. Our results lay a foundation for further investigation of the role of CmLOB27 and CmERF72 transcription factors in the process of anther dehiscence in chrysanthemum.

Asunto(s)

Chrysanthemum , Flores , Perfilación de la Expresión Génica , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación de la Expresión Génica de las Plantas/fisiología , Pectinas , Proteínas de Plantas , Poligalacturonasa , Chrysanthemum/enzimología , Chrysanthemum/genética , Flores/enzimología , Flores/genética , Pectinas/genética , Pectinas/metabolismo , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/genética , Poligalacturonasa/biosíntesis , Poligalacturonasa/genética

RESUMEN

Three Chrysanthemum-chalcone-isomerase genes( CmCHI) were successfully cloned by PCR from the database of Chrysanthemum transcriptome and named CmCHI1,CmCHI2 and CmCHI3,respectively. Bioinformatics analysis showed that the base numbers of CmCHI1-3 open reading frame were 708,633 and 681 bp,encoding 235,210 and 226 amino acids,respectively. Three fusion proteins of about 30 kDa were successfully induced by prokaryotic expression technology,and the corresponding recombinant fusion proteins were isolated and purified by Ni-NTA resin column. Clustering analysis showed that the 3 CmCHI were homologous with Compositae plants,and CmCHI1 and CmCHI3 belonged to type Ⅰ CHI. CmCHI2 belongs to type Ⅳ CHI. Using ß-actin as an internal reference gene,RT-qPCR was used to detect and analyze the expression of CmCHI1-3 genes in Hangju. The results showed that the expression levels of CmCHI1 and CmCHI3 were higher,while the expression levels of CmCHI2 were lower. It was concluded that CmCHI1 and CmCHI3 were the main chalcone isomerase genes involved in the synthesis of flavonoids in Hangju,and CmCHI2 was a helper gene. Flooding treatment significantly promoted the expression of CmCHI1 and CmCHI3 genes,but had no regulatory effect on CmCHI2. The above results provided a basis for further study of the molecular regulation mechanism of CHI gene in the metabolism of flavonoids in Hangju,which laid a foundation for improving the content of flavonoids in Hangju and finally improving the medicinal quality of Hangju.

Asunto(s)

Chrysanthemum/genética , Liasas Intramoleculares/genética , Proteínas de Plantas/genética , Chrysanthemum/enzimología , Clonación Molecular

RESUMEN

We cloned flavonol synthase gene (named as CmFLS) by RACE from Chrysanthemum morifolium cv. 'Hangju' based on transcriptome database. Sequencing results showed that 1 235 bp sequence was acquired with the largest open reading frame (ORF) of 1 008 bp, which encoded 335 amino acids. The predicted CmFLS encoded protein had an isoelectric point (pI) of 5.41. The phylogenetic tree analysis indicated that CmFLS was highly homologous to other FLSs, which identified from the species of Compositae. The recombinant fusion protein, with a molecular mass of 43 kDa, was successfully expressed by prokaryotic expression system. Meanwhile, Ni-NTA resin was used to purify the recombinant fusion protein, and the Ni-Native Buffer containing 250 mmol·L⁻¹ imidazole was most favorable for elution. The purified recombinant fusion protein was subjected to in vitro catalytic reaction, and then the products were extracted and analyzed by HPLC. The results showed that the recombinant fusion protein CmFLS was able to catalyze the production of quercetin by dihydroquercetin under specific buffer and reaction conditions, which indicated that the functional protein encoded by CmFLS had dioxygenase activity in the biosynthetic pathway of flavonoids biosynthesis in Ch. morifolium cv. 'Hangju'. The above results laid the foundation for further studying on CmFLS, and provided new ideas for the regulation of flavonoids metabolism from the molecular level and the catalytic synthesis of flavonols in vitro.

Asunto(s)

Chrysanthemum/enzimología , Oxidorreductasas/química , Proteínas de Plantas/química , Clonación Molecular , Filogenia

RESUMEN

To investigate the effects of the expression of flavonoid 3' hydroxylase gene (F3'H) and active ingredients in Chrysanthemum morifolium under flooding stress, we cloned F3'H from Hangju (temporarily named CmF3'H) and conducted bioinformatics analysis. During the flower bud differentiation stage, we flooded the Ch. morifolium and then used the Real-time PCR to detect the relative expression of CmF3'H; Finally, active ingredients of the inflorescence were measured by HPLC.The sequencing results showed that 1 562 bp sequence was acquired with the largest open reading frame of 1 527 bp, which encoded 508 amino acids. The phylogenetic tree found that CmF3'H was highly homologous to other species of Compositae. Real-time PCR results showed that CmF3'H had a significant response to flooding stress and had the highest expression level after flooding for 24 h, which was about 9 times as that of the control group. The results of HPLC showed that luteolin and luteoloside, the downstream products catalyzed by the F3'H, were significantly higher than those in the control group. It was also found that the contents of chlorogenic acid and 3,5-O-di-caffeoylquinic acid were also significantly higher than those of the control group. Therefore, Ch. morifolium regulates the synthesis of downstream products by regulating the expression of CmF3'H in the flavonoid synthesis pathway under flooding stress, thereby responding to flooding stress. The flooding stress during flower bud differentiation can significantly enhance the accumulation of active ingredients.

Asunto(s)

Chrysanthemum/enzimología , Sistema Enzimático del Citocromo P-450/genética , Inundaciones , Proteínas de Plantas/genética , Estrés Fisiológico , Chrysanthemum/genética , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Glucósidos/biosíntesis , Luteolina/biosíntesis , Filogenia

RESUMEN

Aphids are pests of chrysanthemum that employ plant volatiles to select host plants and ingest cell contents to probe host quality before engaging in prolonged feeding and reproduction. Changes in volatile and nonvolatile metabolite profiles can disrupt aphid-plant interactions and provide new methods of pest control. Chrysanthemol synthase (CHS) from Tanacetum cinerariifolium represents the first committed step in the biosynthesis of pyrethrin ester insecticides, but no biological role for the chrysanthemol product alone has yet been documented. In this study, the TcCHS gene was over-expressed in Chrysanthemum morifolium and resulted in both the emission of volatile chrysanthemol (ca. 47 pmol/h/gFW) and accumulation of a chrysanthemol glycoside derivative, identified by NMR as chrysanthemyl-6-O-malonyl-ß-D-glucopyranoside (ca. 1.1 mM), with no detrimental phenotypic effects. Dual-choice assays separately assaying these compounds in pure form and as part of the headspace and extract demonstrated independent bioactivity of both components against the cotton aphid (Aphis gossypii). Performance assays showed that the TcCHS plants significantly reduced aphid reproduction, consistent with disturbance of aphid probing activities on these plants as revealed by electropenetrogram (EPG) studies. In open-field trials, aphid population development was very strongly impaired demonstrating the robustness and high impact of the trait. The results suggest that expression of the TcCHS gene induces a dual defence system, with both repellence by chrysanthemol odour and deterrence by its nonvolatile glycoside, introducing a promising new option for engineering aphid control into plants.

Asunto(s)

Transferasas Alquil y Aril/metabolismo , Áfidos/patogenicidad , Chrysanthemum/enzimología , Chrysanthemum/parasitología , Proteínas de Plantas/metabolismo , Animales , Chrysanthemum/metabolismo , Glicósidos/metabolismo , Terpenos/metabolismo

RESUMEN

The study is aimed at determine the content of anthocyanins and expressions of relative genes and activity of relative enzymes. The effects of flood stress on anthocyanins synthesis with relative genes and enzymes of Chrysanthemum morifolium cv. 'Hangju' were analyzed. The expression of CHS and the content of CHS presented the trend of first rising and after downward with the increase of flowering degree. The content of anthocyanins, the expression of DFR and the activity of DFR presented the trend of first downward and after rising with the increase of flowering degree. There was a positive correlation among anthocyanins,DFR gene and DFR. However there was no significant correlation among anthocyanins,CHS gene and CHS. Flood stress has significant effects on anthocyanins synthesis with relative genes and enzymes of Ch. morifolium cv. 'Hangju',but don't change the patterns of genes expression and anthocyanins and enzymes accumulation. DFR and DFR are the key gene and key enzyme of anthocyanins synthesis.

Asunto(s)

Antocianinas/biosíntesis , Chrysanthemum/enzimología , Inundaciones , Aciltransferasas/genética , Chrysanthemum/genética , Chrysanthemum/fisiología , Flores/fisiología , Regulación de la Expresión Génica de las Plantas , Genes de Plantas

RESUMEN

Salinity-stressed plants of salinity sensitive ('Qx096') and tolerant ('Qx097') chrysanthemum cultivar were treated with a range of concentrations of spermidine (Spd). Plant performance, as indicated by various parameters associated with growth, was improved by the treatment, as was the tissue content of soluble protein and proline. The extent of both Na(+) accumulation and K(+) loss was reduced. Activity levels of the stress-related enzymes SOD, POD, APX and CAT were significantly increased and the production of malondialdehyde (MDA) decreased. The suggestion was that treatment with 1.5 mM Spd would be an effective means alleviating salinity-stress induced injury through its positive effect on photosynthetic efficiency, reactive oxygen species scavenging ability and the control of ionic balance and osmotic potential. Its protective capacity was more apparent in 'Qx096' than in 'Qx097'.

Asunto(s)

Chrysanthemum/fisiología , Salinidad , Plantones/fisiología , Espermidina/farmacología , Estrés Fisiológico/efectos de los fármacos , Antioxidantes/metabolismo , Chrysanthemum/efectos de los fármacos , Chrysanthemum/enzimología , Chrysanthemum/crecimiento & desarrollo , Electrólitos/metabolismo , Malondialdehído/metabolismo , Fotosíntesis/efectos de los fármacos , Desarrollo de la Planta/efectos de los fármacos , Proteínas de Plantas/metabolismo , Potasio/metabolismo , Prolina/metabolismo , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Sodio/metabolismo , Solubilidad

RESUMEN

Sustained monoculture often leads to a decline in soil quality, in particular to the build-up of pathogen populations, a problem that is conventionally addressed by the use of either fungicide and/or soil fumigation. This practice is no longer considered to be either environmentally sustainable or safe. While the application of organic fertilizer is seen as a means of combating declining soil fertility, it has also been suggested as providing some control over certain soil-borne plant pathogens. Here, a greenhouse comparison was made of the Fusarium wilt control efficacy of various treatments given to a soil in which chrysanthemum had been produced continuously for many years. The treatments comprised the fungicide carbendazim (MBC), the soil fumigant dazomet (DAZ), the incorporation of a Paenibacillus polymyxa SQR21 (P. polymyxa SQR21, fungal antagonist) enhanced bio-organic fertilizer (BOF), and applications of BOF combined with either MBC or DAZ. Data suggest that all the treatments evaluated show good control over Fusarium wilt. The MBC and DAZ treatments were effective in suppressing the disease, but led to significant decrease in urease activity and no enhancement of catalase activity in the rhizosphere soils. BOF including treatments showed significant enhancement in soil enzyme activities and microbial communities compared to the MBC and DAZ, evidenced by differences in bacterial/fungi (B/F) ratios, Shannon-Wiener indexes and urease, catalase and sucrase activities in the rhizosphere soil of chrysanthemum. Of all the treatments evaluated, DAZ/BOF application not only greatly suppressed Fusarium wilt and enhanced soil enzyme activities and microbial communities but also promoted the quality of chrysanthemum obviously. Our findings suggest that combined BOF with DAZ could more effectively control Fusarium wilt disease of chrysanthemum.

Asunto(s)

Bencimidazoles/farmacología , Carbamatos/farmacología , Chrysanthemum/microbiología , Fertilizantes/microbiología , Fusarium/efectos de los fármacos , Paenibacillus/crecimiento & desarrollo , Enfermedades de las Plantas/prevención & control , Tiadiazinas/farmacología , Chrysanthemum/enzimología , Fumigación/métodos , Fungicidas Industriales/farmacología , Efecto Invernadero , Enfermedades de las Plantas/microbiología , Raíces de Plantas/enzimología , Rizosfera , Suelo/química , Microbiología del Suelo

RESUMEN

The paper mainly studied the effects of enhanced UV-B radiation on the nutritional and active ingredient contents during the floral development of medicinal chrysanthemum. The experiment included two levels of UV-B radiation (0 and 400µWcm(-2)). The contents of hydrogen peroxide (H2O2), anthocyanin, UV-B absorbing compounds, total chlorophyll and carotenoids, and the activities of phenylalanine ammonia lyase enzyme (PAL) and cinnamic acid-4-hydroxylase enzyme (C4H) in flowers significantly decreased with the floral development. However, the contents of soluble sugar, amino acid and total vitamin C in flowers significantly increased with the floral development. The contents of flavonoid and chlorogenic acid were significantly different in the four stages of floral development, and their highest contents were found in the bud stage (stage 2). In the four stages of floral development, enhanced UV-B radiation significantly increased the contents of H2O2, UV-B absorbing compounds, chlorophyll, carotenoids, soluble sugar, amino acid, vitamin C, flavonoid and chlorogenic acid, and the activities of PLA and C4H in flowers. The results indicated that the highest contents of active and nutrient ingredients in flowers were found not to be in the same developmental stages of flowers. Comprehensive analysis revealed that the best harvest stage of chrysanthemum flowers was between the bud stage and the young flower stage (stage 2 and stage 3), which could simultaneously gain the higher contents of active and nutritional ingredients in flowers.

Asunto(s)

Chrysanthemum/metabolismo , Flores/crecimiento & desarrollo , Plantas Medicinales/metabolismo , Rayos Ultravioleta , Chrysanthemum/enzimología , Chrysanthemum/crecimiento & desarrollo , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Plantas Medicinales/enzimología , Plantas Medicinales/crecimiento & desarrollo

RESUMEN

Genetic engineering of roses and other plants of floricultural importance to give them a truly blue petal color is arguably one of the holy grails of plant biotechnology. Toward this goal, bluish carnations and roses were previously engineered by establishing an exclusive accumulation of delphinidin (Dp)-type anthocyanins in their petals via the heterologous expression of a flavonoid 3',5'-hydroxylase gene. Very recently, purple-blue varieties of chrysanthemums were also genetically engineered via a similar biochemical strategy. Although the floral colors of these transgenic plants still lack a true blue color, the basis for the future molecular breeding of truly blue flowers is via the engineering of anthocyanin pathways. Anthocyanins with multiple aromatic acyl groups (often referred to as polyacylated anthocyanins) in the 3'- or 7-position tend to display a more stable blue color than non-acylated anthocyanins. The 7-polyacylation process during the biosynthesis of purple-blue anthocyanins in delphinium (Delphinium grandiflorum) was found to occur in vacuoles using acyl-glucose as both the glucosyl and acyl donor. Glucosyltransferases and acyltransferases involved in anthocyanin 7-polyacylation in delphinium are vacuolar acyl-glucose-dependent enzymes belonging to the glycoside hydrolase family 1 and serine carboxypeptidae-like protein family, respectively. The 7-polyacylation proceeds through the alternate glucosylation and p-hydroxybenzoylation catalyzed by these enzymes. p-Hydroxybenzoyl-glucose serves as the p-hydroxybenzoyl and glucosyl donor to produce anthocyanins modified with a p-hydroxybenzoyl-glucose concatemer at the 7-position. This novel finding has provided a potential breakthrough for the genetic engineering of truly blue flowers, where polyacylated Dp-type anthocyanins are accumulated exclusively in the petals.

Asunto(s)

Antocianinas/química , Chrysanthemum/química , Flores/química , Rosa/química , Aciltransferasas/genética , Aciltransferasas/metabolismo , Antocianinas/metabolismo , Chrysanthemum/enzimología , Chrysanthemum/genética , Color , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Barajamiento de ADN , Delphinium/química , Delphinium/metabolismo , Flores/enzimología , Flores/genética , Ingeniería Genética , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Pigmentación , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Rosa/enzimología , Rosa/genética

RESUMEN

The article studied UV-B effects on biochemical parameters and active ingredients in flowers of Qi chrysanthemum and Huai chrysanthemum during the bud stage. The experiment included four UV-B radiation levels (CK, ambient UV-B; T1, T2 and T3 indicated a 5%, 10% and 15% increase in ambient UV-BBE, respectively) to determine the optimal UV-B radiation intensity in regulating active ingredients level in flowers of two chrysanthemum varieties. Flower dry weight of two cultivars was not affected by UV-B radiation under experimental conditions reported here. UV-B treatments significantly increased the rate of superoxide radical production, hydrogen peroxide (H2O2) (except for T1) and malondialdehyde concentration in flowers of Huai chrysanthemum and H2O2 concentration in flowers of Qi chrysanthemum. T2 and T3 treatments induced a significant increase in phenylalanine ammonia lyase enzyme (PAL) activity, anthocyanins, proline, ascorbic acid, chlorogenic acid and flavone content in flowers of two chrysanthemum varieties, and there were no significant differences in PAL activity, ascorbic acid, flavone and chlorogenic acid content between the two treatments. These results indicated that appropriate UV-B radiation intensity did not result in the decrease in flower yield, and could regulate PAL activity and increase active ingredients content in flowers of two chrysanthemum varieties.

Asunto(s)

Chrysanthemum/efectos de la radiación , Flores/efectos de la radiación , Rayos Ultravioleta , Antocianinas/metabolismo , Ácido Ascórbico/metabolismo , Ácido Clorogénico/metabolismo , Chrysanthemum/enzimología , Chrysanthemum/metabolismo , Flavonas/metabolismo , Flores/enzimología , Flores/metabolismo , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Fenilanina Amoníaco-Liasa/metabolismo , Prolina/metabolismo , Superóxidos/metabolismo

RESUMEN

BACKGROUND: Chrysanthemum is one of the most important ornamental crops in the world and drought stress seriously limits its production and distribution. In order to generate a functional genomics resource and obtain a deeper understanding of the molecular mechanisms regarding chrysanthemum responses to dehydration stress, we performed large-scale transcriptome sequencing of chrysanthemum plants under dehydration stress using the Illumina sequencing technology. RESULTS: Two cDNA libraries constructed from mRNAs of control and dehydration-treated seedlings were sequenced by Illumina technology. A total of more than 100 million reads were generated and de novo assembled into 98,180 unique transcripts which were further extensively annotated by comparing their sequencing to different protein databases. Biochemical pathways were predicted from these transcript sequences. Furthermore, we performed gene expression profiling analysis upon dehydration treatment in chrysanthemum and identified 8,558 dehydration-responsive unique transcripts, including 307 transcription factors and 229 protein kinases and many well-known stress responsive genes. Gene ontology (GO) term enrichment and biochemical pathway analyses showed that dehydration stress caused changes in hormone response, secondary and amino acid metabolism, and light and photoperiod response. These findings suggest that drought tolerance of chrysanthemum plants may be related to the regulation of hormone biosynthesis and signaling, reduction of oxidative damage, stabilization of cell proteins and structures, and maintenance of energy and carbon supply. CONCLUSIONS: Our transcriptome sequences can provide a valuable resource for chrysanthemum breeding and research and novel insights into chrysanthemum responses to dehydration stress and offer candidate genes or markers that can be used to guide future studies attempting to breed drought tolerant chrysanthemum cultivars.

Asunto(s)

Chrysanthemum/genética , Chrysanthemum/fisiología , Genoma de Planta/genética , Análisis de Secuencia de ADN , Estrés Fisiológico/genética , Transcriptoma/genética , Ácido Abscísico/biosíntesis , Secuencia de Bases , Vías Biosintéticas/genética , Chrysanthemum/enzimología , Bases de Datos Genéticas , Deshidratación , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Anotación de Secuencia Molecular , Prolina/biosíntesis , Proteínas Quinasas/genética , Proteínas Quinasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/metabolismo

RESUMEN

A PCR strategy was used to isolate a full-length CgADH (alcohol dehydrogenase) cDNA from chrysanthemum. The gene putatively encodes a 378 residue polypeptides, which shares 95% homology with tomato alcohol dehydrogenase class III. Endogenous ethylene generated in waterlogged Chrysanthemum zawadskii was enhanced by exogenous ethylene but decreased by 1-methylcyclopropene (1-MCP), an inhibitor of ethylene action. In waterlogged roots, the transcription of the gene encoding alcohol dehydrogenase (ADH, EC 1.1.1.1) increased rapidly but transiently, peaking at 7.5 fold the non-waterlogged level after 2h of stress. Waterlogging elevated ADH activity after a prolonged episode of stress. The exogenous supply of 40µLL(-1) ethylene suppressed the production of ethanol, while that of 4µLL(-1) 1-MCP enhanced it. Ethylene appeared to suppress an acceleration of both CgADH expression and fermentation, and alleviates ethanolic fermentation probably through by as a signal to acceleration of waterlogging-induced aerenchyma formation. This supports the previously observed phenomenon that the expression level of ADH gene is regulated by the local level of physiologically active ethylene. The relevance of the CgADH gene in relation to chrysanthemum waterlogging was discussed as well.

Asunto(s)

Alcohol Deshidrogenasa/genética , Chrysanthemum/enzimología , Chrysanthemum/genética , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Agua/metabolismo , Alcohol Deshidrogenasa/metabolismo , Secuencia de Aminoácidos , Chrysanthemum/metabolismo , Ciclopropanos/farmacología , ADN Complementario/genética , ADN Complementario/metabolismo , Etanol/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Raíces de Plantas/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Alineación de Secuencia

RESUMEN

Herbivore-induced plant volatiles are often involved in direct and indirect plant defence against herbivores. Linalool is a common floral scent and found to be released from leaves by many plants after herbivore attack. In this study, a linalool/nerolidol synthase, FaNES1, was overexpressed in the plastids of chrysanthemum plants (Chrysanthemum morifolium). The volatiles of FaNES1 chrysanthemum leaves were strongly dominated by linalool, but they also emitted small amount of the C11-homoterpene, (3E)-4,8-dimethyl-1,3,7-nonatriene, a derivative of nerolidol. Four nonvolatile linalool glycosides in methanolic extracts were found to be significantly increased in the leaves of FaNES1 plants compared to wild-type plants. They were putatively identified by LC-MS-MS as two linalool-malonyl-hexoses, a linalool-pentose-hexose and a glycoside of hydroxy-linalool. A leaf-disc dual-choice assay with western flower thrips (WFT, Frankliniella occidentalis) showed, initially during the first 15 min of WFT release, that FaNES1 plants were significantly preferred. This gradually reversed into significant preference for the control, however, at 20-28 h after WFT release. The initial preference was shown to be based on the linalool odour of FaNES1 plants by olfactory dual-choice assays using paper discs emitting pure linalool at similar rates as leaf discs. The reversal of preference into deterrence could be explained by the initial nonvolatile composition of the FaNES1 plants, as methanolic extracts were less preferred by WFT. Considering the common occurrence of linalool and its glycosides in plant tissues, it suggests that plants may balance attractive fragrance with 'poor taste' using the same precursor compound.

Asunto(s)

Chrysanthemum/enzimología , Hidroliasas/genética , Proteínas de Plantas/metabolismo , Thysanoptera/fisiología , Monoterpenos Acíclicos , Cromatografía Liquida , Chrysanthemum/genética , Conducta Alimentaria , Cromatografía de Gases y Espectrometría de Masas , Regulación de la Expresión Génica de las Plantas , Espectrometría de Masas , Monoterpenos/química , Monoterpenos/metabolismo , Control Biológico de Vectores , Proteínas de Plantas/genética , Olfato

RESUMEN

Chrysanthemum lavandulifolium (Fisch. ex Trautv.) Makino is a halophyte species that belongs to the Asteraceae family, and the genus Chrysanthemum. It is one of the ancestors of C.×morifolium Ramatella. Understanding the tolerance mechanism associated with salt stress in C. lavandulifolium could provide important information for explaining the salt tolerance of higher plants and could also help enhancing breeding programs of cultivated Chrysanthemum. In this study, cDNA amplified fragment length polymorphism (cDNA-AFLP) was used to detect differential gene expression in leaves of C. lavandulifolium in response to NaCl treatment. The determination of membrane permeablility, peroxidase activity (POD), malon-dialdehyde (MDA), as well as proline and leaf chlorophyll contents under different NaCl concentrations showed that a 200 mM NaCl treatment was an optimal condition for the cDNA-AFLP experiment. Using this concentration during different times (0, 3 h, 12 h, 24 h and 48 h), we obtained 1930 cDNA fragments using 64 primers. After sequencing 234 randomly chosen cDNA clones and BLASTx analyzing, we got 129 expressed sequence tags (ESTs) which had no significant homology with other sequences, 85 ESTs were homologous to genes with known functions, whereas the rest of ESTs showed homology to unclassified or putative proteins. 25 ESTs that were similar to known functional genes involved in several abiotic and biotic stresses were confirmed by semi-quantitative RT-PCR and qRT-PCR. The expression patterns of these salt-responsive genes not only responded to salt stress but also to plant hormones, such as abscisic acid (ABA), and to other abiotic stresses such as drought and cold. These results indicate an extensive cross-talk among several stresses. Our results provide interesting information for further understanding the molecular mechanisms of salt tolerance in C. lavandulifolium.

Asunto(s)

Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/métodos , Chrysanthemum/genética , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Tolerancia a la Sal/genética , Cloruro de Sodio/farmacología , Estrés Psicológico/genética , Ácido Abscísico/farmacología , Permeabilidad de la Membrana Celular/efectos de los fármacos , Clorofila/metabolismo , Chrysanthemum/efectos de los fármacos , Chrysanthemum/enzimología , Chrysanthemum/fisiología , Frío , ADN Complementario/genética , Sequías , Etiquetas de Secuencia Expresada , Genes de Plantas/genética , Malondialdehído/metabolismo , Peroxidasa/efectos de los fármacos , Peroxidasa/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/enzimología , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Plantas Tolerantes a la Sal , Análisis de Secuencia de ADN , Factores de Tiempo

RESUMEN

OBJECTIVE: To study the effect of waterlogging stress on medicinal Chrysanthemum morifolium during the seedling stage and build a reliable evaluation of flooding tolerance indicator system. METHOD: The three cultivars: C. morifolium cv. Hongxinju, C. morifolium cv. Xiaobaiju and C. morifolium cv. Changbanju were studied for the and the effect of waterlogging stress on their physiological and biochemical chracteristics. RESULT: With the extension of waterlogging, the content of chlorophyll and relative leaf water potential were decreased, meanwhile malonaldehyde (MDA), glutathione (GSH) and soluble sugar were increased. The catalase (CAT) of C. morifolium cv. Hongxinju rose at first and then dropped and CAT of C. morifolium cv. Xiaobailu and C. morifolium cv. Changbanju declined at first before decreased, and then dropped again. The peroxidase (POD) rose firstly before decrease and then increases again. After the waterlogging treatments which last for 4 days, the physiology and biochemistry characteristics can not restore to the comparison (CK) within 3 days. CONCLUSION: Four days waterlogging treatment had made serious damage on medicinal Chrysanthemum. Among three cultivars, C. morifolium Ramat. cv. Hongxinju showed the highest tolerance ability, while C. morifolium cv. Changbanju was the lowest, and C. morifolium cv. Xiaobaiu was in the middle. The malonaldehyde (MDA) and catalase (CAT) could be the main physiological and biochemical indexes to reflect the tolerance ability against waterlogging.

Asunto(s)

Chrysanthemum/química , Chrysanthemum/fisiología , Agua/metabolismo , Metabolismo de los Hidratos de Carbono , Carbohidratos/análisis , Catalasa/análisis , Catalasa/metabolismo , Chrysanthemum/enzimología , Deshidratación , Malondialdehído/análisis , Malondialdehído/metabolismo , Peroxidasa/análisis , Peroxidasa/metabolismo , Proteínas de Plantas/análisis , Proteínas de Plantas/metabolismo , Plantones/química , Plantones/enzimología , Plantones/fisiología