Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 140
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Protoplasma ; 256(6): 1507-1517, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31168667

RESUMO

Gibberellins (GAs), as one of the important hormones in regulating the growth and development of higher plants, can significantly promote cell elongation and expansion. Celery is a widely grown leafy vegetable crop with rich nutritional value. However, the effect of gibberellins on celery leaves is unclear. In this paper, the celery variety "Jinnan Shiqin" plants were treated with gibberellic acid (GA3) and paclobutrazol (PBZ, a gibberellin inhibitor). Our results showed that GA3 treatment promoted the growth of celery leaves and caused lignification of celery leaf tissue. In addition, the transcript levels of genes associated with gibberellins, auxin, cytokinins, ethylene, jasmonic acid, abscisic acid, and brassinolide were altered in response to increased or decreased exogenous gibberellins or inhibitor. GA3 may regulate celery growth by interacting with other hormones through crosstalk mechanisms. This study provided a reference for further study of the regulation mechanism of gibberellins metabolism, and exerted effects on understanding the role of gibberellins in the growth and development of celery.

2.
Plant Physiol ; 181(1): 195-207, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31213511

RESUMO

The original domesticated carrots (Daucus carota) are thought to have been purple, accumulating large quantities of anthocyanins in their roots. A quantitative trait locus associated with anthocyanin pigmentation in purple carrot roots has been identified on chromosome 3 and includes two candidate genes, DcMYB6 and DcMYB7 Here, we characterized the functions of DcMYB6 and DcMYB7 in carrots. Overexpression of DcMYB7, but not DcMYB6, in the orange carrot 'Kurodagosun' led to anthocyanin accumulation in roots. Knockout of DcMYB7 in the solid purple (purple periderm, phloem, and xylem) carrot 'Deep Purple' using the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 system resulted in carrots with yellow roots. DcMYB7 could activate the expression of its DcbHLH3 partner, a homolog of the anthocyanin-related apple (Malus × domestica) bHLH3, and structural genes in the anthocyanin biosynthetic pathway. We determined that the promoter sequence of DcMYB7 in nonpurple carrots was interrupted either by DcMYB8, a nonfunctional tandem duplication of DcMYB7, or by two transposons, leading to the transcriptional inactivation of DcMYB7 in nonpurple carrot roots. As a result, nonpurple carrots fail to accumulate anthocyanins in their roots. Our study supports the hypothesis that another genetic factor suppresses DcMYB7 expression in the phloem and xylem of purple peridermal carrot root tissues. DcMYB7 also regulated the glycosylation and acylation of anthocyanins by directly activating DcUCGXT1 and DcSAT1 We reveal the genetic factors conditioning anthocyanin pigmentation in purple versus nonpurple carrot roots. Our results also provide insights into the mechanisms underlying anthocyanin glycosylation and acylation.

3.
Planta ; 250(4): 1265-1280, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31236696

RESUMO

MAIN CONCLUSION: This study analyzed the AP2/ERF transcription factors in celery and showed that two dehydration-responsive-element-binding (DREB) transcription factors, AgDREB1 and AgDREB2, contribute to the enhanced resistance to abiotic stress in transgenic Arabidopsis. The AP2/ERF family is a large family of transcription factors (TFs) in higher plants that plays a central role in plant growth, development, and response to environmental stress. Here, 209 AP2/ERF family members were identified in celery based on genomic and transcriptomic data. The TFs were classified into four subfamilies (i.e., DREB, ERF, RAV, and AP2) and Soloist. Evolution analysis indicated that the AP2/ERF TFs are ancient molecules and have expanded in the long-term evolution process of plants and whole-genome duplication events. AgAP2/ERF proteins may be associated with multiple biological processes as predicted by the interaction network. The expression profiles and sequence alignment analysis of the TFs in the DREB-A1 group showed that eight genes could be divided into four branches. Two genes, AgDREB1 and AgDREB2, from the DREB-A1 group were selected for further analysis. Subcellular localization assay suggested that the two proteins are nuclear proteins. Yeast one hybrid assay demonstrated that the two proteins could bind to the dehydration-responsive element (DRE). The overexpression of AgDREB1 and AgDREB2 in Arabidopsis induced the increased tolerance to cold treatment and the up-regulation of the COR genes expression. AgDREB1 and AgDREB2 might function as transcriptional activators in regulating the downstream genes by binding to corresponding DRE to enhance stress tolerance in celery.

4.
Crit Rev Biotechnol ; 39(5): 680-692, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31068014

RESUMO

Biotic stress is one of the key factors that restrict the growth and development of plants. Fruit crops are mostly perennial, so they are more seriously endangered by biotic stress. Plant responses to different types of biotic stresses such as pathogens and insects are controlled by a very complex regulatory and defense system. High-throughput sequencing (next-generation sequencing) has brought powerful research strategies and methods to the research fields of genomics and post-genomics. Functional genomics, transcriptomics, proteomics, metabolomics, and deep-sequencing of small RNAs provides a new path to better understand the complex regulatory and defense systems behind biotic stress in plants. In this review, we summarized recent progresses in research on fruit crops responses to biotic stress using genomics, transcriptomics, proteomics, metabolomics, and deep-sequencing approaches. This paper also summarized the information of SNP marker resources and the transcription factors that are involved in the regulation of biotic stress responses obtained from genome sequencing, and discusses the differential expression of related genes and proteins identified by transcriptome and proteome sequencing. At the same time, the roles of signaling pathways and metabolites involved in plant biotic stress revealed by the metabolome have also been discussed. In addition, the application of small RNA deep sequencing in the study of fruit crop response to biotic stress has also been included in this review. These omics and deep sequencing methods will greatly support the biotic resistance-resistant breeding of fruit crops.


Assuntos
Frutas/genética , Frutas/metabolismo , Genoma de Planta , Estresse Fisiológico , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Genômica , Metabolômica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transcriptoma
5.
BMC Plant Biol ; 19(1): 173, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046667

RESUMO

BACKGROUND: In higher plants, salicylic acid (SA) plays important roles in inducing resistance to biotic and abiotic stresses. Tomato yellow leaf curl virus (TYLCV) causes a highly devastating viral disease in plants, particularly in tomato. However, the roles of SA in inducing tomato plant resistance to TYLCV remain unclear. RESULTS: In this study, we investigated whether the exogenous application of SA can improve the resistance of tomato plants to TYLCV in two tomato cultivars, resistant 'Zhefen-702' and susceptible 'Jinpeng-1'. The impacts of SA on the accumulation of ascorbic acid (AsA) and biosynthetic gene expression, the activity of some important reactive oxygen species (ROS)-scavenging enzymes, and the expression patterns of stress-related genes were also determined. Results indicated that SA can effectively regulate the accumulation of AsA, especially in 'Jinpeng-1'. Similarly, the expression patterns of most of the AsA biosynthetic genes showed a negative relationship with AsA accumulation in the resistant and susceptible tomato cultivars. In the two tomato cultivars, the activities of ascorbate peroxidase (APX) and peroxidase (POD) in the SA + TYLCV treated plants were increased during the experiment period except at 14 days (APX in 'Jinpeng-1' was also at 4 days) post infected (dpi) with TYLCV. Simultaneously, the activity of SOD was reduced in 'Jinpeng-1' and increased in 'Zhefen-702' after treatment with SA + TYLCV. SA can substantially induce the expression of ROS-scavenging genes at different extents. From 2 to 10 dpi, the virus content in the SA + TYLCV treated plants was remarkably lower than those in the TYLCV treated plants in 'Jinpeng-1'and Zhefen-702'. CONCLUSIONS: The above results suggest that SA can enhance tomato plant resistance by modulating the expression of genes encoding for ROS-scavenging players, altering the activity of resistance-related enzymes, and inducing the expression of pathogenesis-related genes to produce systemic acquired resistance. Simultaneously, these results confirm that SA is a resistance-inducing factor against TYLCV infection that can be effectively applied in tomato plants.


Assuntos
Begomovirus , Doenças das Plantas/virologia , Ácido Salicílico/metabolismo , Resistência à Doença , Suscetibilidade a Doenças , Doenças das Plantas/genética
6.
Mol Biotechnol ; 61(3): 191-199, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30644027

RESUMO

The clustered regularly interspaced short palindromic repeats (CRISPR)-associated protein 9 (Cas9) system has been successfully used for precise genome editing in many plant species, including in carrot cells, very recently. However, no stable gene-editing carrot plants were obtained with CRISPR/Cas9 system to date. In the present study, four sgRNA expression cassettes, individually driven by four different promoters and assembled in a single CRISPR/Cas9 vector, were transformed into carrots using Agrobacterium-mediated genetic transformation. Four sites of DcPDS and DcMYB113-like genes were chosen as targets. Knockout of DcPDS in orange carrot 'Kurodagosun' resulted in the generation of albino carrot plantlets, with about 35.3% editing efficiency. DcMYB113-like was also successfully edited in purple carrot 'Deep purple', resulting in purple depigmented carrot plants, with about 36.4% rate of mutation. Sequencing analyses showed that insertion, deletion, and substitution occurred in the target sites, generating heterozygous, biallelic, and chimeric mutations. The highest efficiency of mutagenesis was observed in the sites targeted by AtU6-29-driven sgRNAs in both DcPDS- and DcMYB113-like-knockout T0 plants, which always induced double-strand breaks in the target sites. Our results proved that CRISPR/Cas9 system could be for generating stable gene-editing carrot plants.


Assuntos
Citrus sinensis/crescimento & desenvolvimento , Daucus carota/crescimento & desenvolvimento , Mutagênese Sítio-Dirigida/métodos , Proteínas de Plantas/genética , Agrobacterium , Sistemas CRISPR-Cas , Citrus sinensis/genética , Daucus carota/genética , Edição de Genes/métodos , Taxa de Mutação , RNA Guia/genética , Análise de Sequência de DNA , Transformação Bacteriana
7.
Protoplasma ; 256(3): 777-788, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30604245

RESUMO

Gibberellin (GA) is a phytohormone of a biguanide compound that plays an important role throughout the life cycle of a plant. Lignin, a phenylalanine-derived aromatic polymer, can enhance the water transport function and structural resistance of cell walls. This function is also the core on biology of higher terrestrial plants. An appropriate lignin level is important to the quality of leafy vegetables, such as celery. The relationship between gibberellin levels and the occurrence of lignification has not been reported in celery. In this study, the leaf blades and petioles of celery cultivars 'Liuhe Huangxinqin' and 'Jinnan Shiqin' were used as materials, and different concentrations of exogenous gibberellin were applied to analyze the growth and lignin distribution of leaf blades and petioles. It was found that gibberellin treatment could influence the lignin content in celery leaves. Autofluorescence analysis under ultraviolet (UV) excitation showed that gibberellin treatment caused lignification of celery leaf tissue. The expression profiles of 12 genes related to lignin synthesis changed with the increase of gibberellin concentration. Our results showed that gibberellin played a significant role in the accumulation of lignin in the development of celery leaves. This provides a basis for further study on the regulation of lignin metabolism in plants and exerts a vital part in the application of plant growth regulators to production.


Assuntos
Apium/metabolismo , Giberelinas/farmacologia , Lignina/metabolismo , Folhas de Planta/metabolismo , Apium/anatomia & histologia , Apium/genética , Apium/crescimento & desenvolvimento , Vias Biossintéticas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estudos de Associação Genética , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Mapas de Interação de Proteínas/efeitos dos fármacos
9.
Plant Physiol Biochem ; 135: 87-98, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30529171

RESUMO

Salt stress is one of the environmental factors that evidently limit plant growth and yield. Despite the fact that understanding plant response to salt stress is important to agricultural practice, the molecular mechanisms underlying salt tolerance in garlic remain unclear. In this study, garlic seedlings were exposed to 200 mM NaCl stress for 0, 1, 4, and 12 h, respectively. RNA-seq was applied to analyze the transcriptional response under salinity conditions. A total of 13,114 out of 25,530 differentially expressed unigenes were identified to have pathway annotation, which were mainly involved in purine metabolism, starch and sucrose metabolism, plant hormone signal transduction, flavone and flavonol biosynthesis, isoflavonoid biosynthesis, MAPK signaling pathway, and circadian rhythm. In addition, 272 and 295 differentially expressed genes were identified to be cell wall and hormone signaling-related, respectively, and their interactions under salinity stress were extensively discussed. The results from the current work would provide new resources for the breeding aimed at improving salt tolerance in garlic.


Assuntos
Parede Celular/fisiologia , Alho/fisiologia , Reguladores de Crescimento de Planta/fisiologia , Alho/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Ontologia Genética , Genes de Plantas/genética , Genes de Plantas/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Estresse Salino , Plântula/fisiologia , Análise de Sequência de RNA , Transdução de Sinais/fisiologia , Transcriptoma
11.
Plant Sci ; 277: 110-120, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30466576

RESUMO

Brassinosteroid (BR) is a predominant plant hormone in regulating cell elongation and cell size. BR-deficient mutants display reduced plant growth and dwarfism in Arabidopsis and rice. In carrot, BRs promote petiole elongation, but its underlying mechanism involving exogenous BR remains unknown. Here, weighted gene co-expression network analysis and promoter region analysis were adopted to identify the potential genes that interacted with DcBZR1/BES1. Bioactive gibberellin (GA) level and cellulose deposition were also determined in the control and treated plants. Quantitative real-time PCR was performed to detect the expression profiles of GA biosynthesis-related genes, GA signaling genes, and cellulose synthase genes. Bioactive GA level and cellulose deposition were upregulated after the petioles were treated with 24-epibrassinolide (24-EBL). The most putative DcBZR1/BES1 genes were clustered in yellow module. The expression level of DCAR_009411 (a GA5-like gene) was significantly induced after 3 h of treatment. The expression levels of DCAR_019754 and DCAR_013973 (CESA-like genes) were also significantly induced after 3 h of 24-EBL treatment. Our results suggested that the effect of BR on carrot petiole growth was quick. These results also provided potential insights into the mechanism by which BRs modulate GA and cellulose synthesis to promote cell elongation in carrot petioles.

12.
Planta ; 248(5): 1249-1261, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30099650

RESUMO

MAIN CONCLUSION: This study showed that an R2R3-MYB transcription factor, AgMYB2, functions in anthocyanin biosynthesis and accumulation in purple celery. Anthocyanins are involved in tissue coloration and stress response in plants. Foods containing high anthocyanin content are also beneficial to human health. Purple celery accumulated amounts of anthocyanins in the petioles. The biosynthesis of anthocyanin in plants is mainly regulated by the R2R3-MYB transcription factor (TF). However, the R2R3-MYB TF that controls anthocyanin accumulation in purple celery remains unclear. In this study, an R2R3-MYB TF gene, AgMYB2, was cloned from purple celery and characterized as anthocyanin biosynthetic regulator. Sequence analysis indicated that AgMYB2 contained highly conserved R2R3 domain and two anthocyanin characteristic motifs, ANDV motif and KPRPR[S/T]F motif. The relative expression level of AgMYB2 in purple celery was significantly higher than that in non-purple celery at three developmental stages. Heterologous expression of AgMYB2 in Arabidopsis generated more anthocyanins and resulted in dark-purple leaves and flowers. The expression levels of anthocyanin biosynthetic genes and the antioxidant activity of transgenic Arabidopsis carrying AgMYB2 were up-regulated. The determination of anthocyanin glycosylation activity of Arabidopsis crude enzyme verified the anthocyanin biosynthesis regulatory function of AgMYB2 at the protein level. The interaction between AgMYB2 and bHLH proteins was shown by yeast two-hybrid assay. The results will help to elucidate the molecular mechanism of anthocyanin biosynthesis in purple celery and provide an approach for cultivating plants with high anthocyanin content.


Assuntos
Antocianinas/biossíntese , Apium/metabolismo , Proteínas de Plantas/fisiologia , Fatores de Transcrição/fisiologia , Apium/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas/genética , Genes de Plantas/genética , Glicosilação , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Fatores de Transcrição/genética , Técnicas do Sistema de Duplo-Híbrido
13.
Database (Oxford) ; 20182018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29992323

RESUMO

Celery (Apium graveolens L.) is a plant belonging to the Apiaceae family, and a popular vegetable worldwide because of its abundant nutrients and various medical functions. Although extensive genetic and molecular biological studies have been conducted on celery, its genomic data remain unclear. Given the significance of celery and the growing demand for its genomic data, the whole genome of 'Q2-JN11' celery (a highly inbred line obtained by artificial selfing of 'Jinnan Shiqin') was sequenced using HiSeq 2000 sequencing technology. For the convenience of researchers to study celery, an online database of the whole-genome sequences of celery, CeleryDB, was constructed. The sequences of the whole genome, nucleotide sequences of the predicted genes and amino acid sequences of the predicted proteins are available online on CeleryDB. Home, BLAST, Genome Browser, Transcription Factor and Download interfaces composed of the organizational structure of CeleryDB. Users can search the celery genomic data by using two user-friendly query tools: basic local alignment search tool and Genome Browser. In the future, CeleryDB will be constantly updated to satisfy the needs of celery researchers worldwide.Database URL: http://apiaceae.njau.edu.cn/celerydb.


Assuntos
Apium/genética , Bases de Dados Genéticas , Genoma de Planta , Alérgenos/genética , Genes de Plantas , Proteínas de Plantas/genética , Alinhamento de Sequência , Fatores de Transcrição/metabolismo , Interface Usuário-Computador
14.
J Agric Food Chem ; 66(30): 8209-8220, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29980166

RESUMO

In our study, isobaric tags for relative and absolute quantification (iTRAQ) was conducted to determine the significantly changed proteins in the fleshy roots of carrots under different carbon dioxide (CO2) treatments. A total of 1523 proteins were identified, of which 257 were differentially expressed proteins (DEPs). On the basis of annotation analysis, the DEPs were identified to be involved in energy metabolism, carbohydrate metabolism, and some other metabolic processes. DcC4H and DcPER, two lignin-related proteins, were identified from the DEPs. Under elevated CO2 stress, both carrot lignin content and the expression profiles of lignin biosynthesis genes changed significantly. The protein-protein interactions among lignin-related enzymes proved the importance of DcC4H and DcPER. The results of our study provided potential new insights into the molecular mechanism of lignin content changes in carrot roots under elevated CO2 stress.


Assuntos
Dióxido de Carbono/metabolismo , Daucus carota/metabolismo , Lignina/análise , Dióxido de Carbono/análise , Daucus carota/química , Daucus carota/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Raízes de Plantas/química , Raízes de Plantas/genética , Raízes de Plantas/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-29909521

RESUMO

The homeobox gene family, a large family represented by transcription factors, has been implicated in secondary growth, early embryo patterning, and hormone response pathways in plants. However, reports about the information and evolutionary history of the homeobox gene family in carrot are limited. In the present study, a total of 130 homeobox family genes were identified in the carrot genome. Specific codomain and phylogenetic analyses revealed that the genes were classified into 14 subgroups. Whole genome and proximal duplication participated in the homeobox gene family expansion in carrot. Purifying selection also contributed to the evolution of carrot homeobox genes. In Gene Ontology (GO) analysis, most members of the HD-ZIP III and IV subfamilies were found to have a lipid binding (GO:0008289) term. Most HD-ZIP III and IV genes also harbored a steroidogenic acute regulatory protein-related lipid transfer (START) domain. These results suggested that the HD-ZIP III and IV subfamilies might be related to lipid transfer. Transcriptome and quantitative real-time PCR (RT-qPCR) data indicated that members of the WOX and KNOX subfamilies were likely implicated in carrot root development. Our study provided a useful basis for further studies on the complexity and function of the homeobox gene family in carrot.

16.
Plant Cell Rep ; 37(7): 1021-1032, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29680943

RESUMO

KEY MESSAGE: Hypoxia enhances lignification of carrot root. Hypoxia stress was thought to be one of the major abiotic stresses that inhibiting the growth and development of higher plants. The genes encoding the plant alcohol dehydrogenase (ADH-P) were induced when suffering hypoxia. To investigate the impact of hypoxia on the carrot root growth, carrot plants were cultivated in the hydroponics with or without aeration. Morphological characteristics, anatomical structure, lignin content, and the expression profiles of DcADH-P genes and lignin biosynthesis-related genes were measured. Six DcADH-P genes were identified from the carrot genome. The expression profiles of only three (DcADH-P1, DcADH-P2, and DcADH-P3) genes could be detected and the other three (DcADH-P4, DcADH-P5, and DcADH-P6) could not be detected when carrot cultivated in the solution without aeration. In addition, carrot roots had more lignin content, aerenchyma and less fresh weight when cultivated in the solution without aeration. These results suggested that hypoxia could enhance the lignification and affect anatomical structure of the carrot root. However, the expression levels of the genes related to lignin biosynthesis were down-regulated under the hypoxia. The enhancement of lignification may be the consequence of the structure changes in the carrot root. Our work was potentially helpful for studying the effect of hypoxia on carrot growth and may provide useful information for carrot hydroponics.


Assuntos
Álcool Desidrogenase/genética , Daucus carota/anatomia & histologia , Hidroponia/métodos , Lignina/metabolismo , Raízes de Plantas/anatomia & histologia , Daucus carota/genética , Daucus carota/crescimento & desenvolvimento , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Hipóxia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento
17.
Plant Physiol Biochem ; 127: 310-319, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29653434

RESUMO

Carbon dioxide (CO2) is an important regulator of plant growth and development, and its proportion in the atmosphere continues to rise now. Lignin is one of the major secondary products in plants with vital biological functions. However, the relationship between CO2 level and xylogenesis in celery is still unknown. In order to investigate the effects of increasing CO2 concentration on lignin accumulation in celery, 'Jinnanshiqin' were exposed to two CO2 applications, 400 (e0) and 1000 µmol mol-1 (e1), respectively. Plant morphology and lignin distribution in celery plants treated with elevated CO2 did not change significantly. There was an upward trend on lignin content in celery leaves, and the transcript abundance of 12 genes involved in lignin metabolism has altered in response to elevated CO2. The effects of high level of CO2 on different tissues were different. Our works confirmed that CO2 may play an important role in lignin accumulation in celery leaves. The current study will offer new evidence to understand the regulation mechanism of lignin biosynthesis under elevated CO2 and provide a reference to improve celery quality by adjusting the growth environment.


Assuntos
Apium/metabolismo , Dióxido de Carbono/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Lignina/biossíntese , Apium/genética , Lignina/genética
18.
Planta ; 247(6): 1363-1375, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29520459

RESUMO

MAIN CONCLUSION: This study showed that a galactosyltransferase, AgUCGalT1, is involved in anthocyanin galactosylation in purple celery. Celery is a well-known vegetable because of its rich nutrients, low calories, and medicinal values. Its petioles and leaf blades are the main organs acting as nutrient sources. UDP-galactose: cyanidin 3-O-galactosyltransferase can transfer the galactosyl moiety from UDP-galactose to the 3-O-position of cyanidin through glycosylation. This process enhances the stability and water solubility of anthocyanins. In the present study, LC-MS data indicated that abundant cyanidin-based anthocyanins accumulated in the petioles of purple celery ('Nanxuan liuhe purple celery'). A gene encoding UDP-galactose: cyanidin 3-O-galactosyltransferase, namely AgUCGalT1, was isolated from purple celery and expressed in Escherichia coli BL21 (DE3). Sequence alignments revealed that the AgUCGalT1 protein contained a highly conserved putative secondary plant glycosyltransferase (PSPG) motif. The glycosylation product catalyzed by AgUCGalT1 was detected using UPLC equipment. The recombinant AgUCGalT1 had an optimal enzyme activity at 35 °C and pH 8.0, and showed highest enzyme activity toward cyanidin among the enzyme activities involving other substances, namely, peonidin, quercetin, and kaempferol. The expression levels of AgUCGalT1 were positively correlated with the total anthocyanin contents in purple and non-purple celery varieties. Crude enzymes extracted from purple celery exhibited glycosylation ability, whereas crude enzymes obtained from non-purple celery did not have this ability. This work provided evidence as a basis for investigations on the function of AgUCGalT1 in anthocyanin glycosylation in purple celery.


Assuntos
Antocianinas/metabolismo , Apium/enzimologia , Galactosiltransferases/metabolismo , Motivos de Aminoácidos , Antocianinas/química , Apium/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Galactosiltransferases/genética , Galactosiltransferases/isolamento & purificação , Glicosilação , Modelos Estruturais , Filogenia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Alinhamento de Sequência
19.
Mol Genet Genomics ; 293(4): 861-871, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29497811

RESUMO

Carrot (Daucus carota L.) is one of the most economically important root vegetables in the world, providing numerous nutrients for human health. China is the largest country of carrot production in the world, and 'Kurodagosun' has been a major carrot variety in China. Carrot material used in this study was the inbred line 'DC-27', which was derived by forced selfing from 'Kurodagosun'. To understand the genetic system and plant-specific genes of 'Kurodagosun', we report the draft genome sequence of carrot 'DC-27' assembled using a combination of Roche454 and HiSeq 2000 sequencing technologies to achieve 32-fold genome coverage. A total of 31,891 predicted genes were identified. These assembled sequences provide candidate genes involved in biological processes including stress response and carotenoid biosynthesis. Genomic sequences corresponding to 371.6 Mb was less than 473 Mb, which is the estimated genome size. The availability of a draft sequence of the 'DC-27' genome advances knowledge on the biological research and breeding of carrot, as well as other Apiaceae plants. The 'DC-27' genome sequence data also provide a new resource to explore the evolution of other higher plants.


Assuntos
Daucus carota/genética , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , Melhoramento Vegetal , Carotenoides/biossíntese , Carotenoides/genética , China , Daucus carota/metabolismo , Japão , Estresse Fisiológico/genética
20.
BMC Plant Biol ; 18(1): 8, 2018 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-29304728

RESUMO

BACKGROUND: Carrot which contains lots of nutrients has a large demand around the world. The soluble sugar content in fleshy root of carrot directly influences its taste and quality. Sucrose, as an important member of soluble sugar, is the main product of photosynthesis in higher plants and it plays pivotal roles in physiological processes including energy supply, signal transduction, transcriptional regulation, starch and cellulose synthesis, and stress tolerance. Sucrose synthase is a key enzyme involved in sucrose metabolism and is closely related to sucrose content. However, the molecular mechanism involved in sucrose metabolism in carrot has lagged behind. RESULTS: Here, carrot roots of five developmental stages from four carrot cultivars were collected, and the contents of soluble sugar and sucrose in different stages and cultivars were surveyed. Three DcSus genes (DcSus1, DcSus2, and DcSus3), with lengths of 2427 bp, 2454 bp and 2628 bp, respectively, were identified and cloned in carrot. Phylogenetic analysis from the deduced amino acid sequences suggested that three DcSus were clustered into three distinct groups (SUSI, II and III). Results of enzymatic profiles demonstrated that the DcSus activities showed decrease trends during taproot development. Correlation analysis indicated that the DcSus activity showed negative correlation with soluble sugar content and strong negative correlation with sucrose concentration. Quantitative real-time PCR analysis showed that the expression profiles of the DcSus genes are significantly different in carrot tissues (root, leaf blade, and petiole), and the expression levels of the DcSus genes in the leaf blade were much higher than that in the root and petiole. The expression profiles of DcSus genes showed strong negative correlation with both sucrose content and soluble sugar content. CONCLUSIONS: During carrot root development, the soluble sugar content and sucrose content showed increasing trends, while DcSus activities had persisting declinations, which may be due to the decreasing expression levels of genes encoding sucrose synthase. Our data demonstrate that synthesis of sucrose in carrot tissue is closely related with DcSus genes. The results from our study would not only provide effective insights of sucrose metabolism in carrot, but also are beneficial for biologists to improve carrot quality.


Assuntos
Daucus carota/genética , Glucosiltransferases/genética , Sacarose/metabolismo , Transcriptoma , Daucus carota/metabolismo , Glucosiltransferases/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA