RESUMO
The 2-(2-phenethyl)chromones (PECs) are the signature constituents responsible for the fragrance and pharmacological properties of agarwood. O-Methyltransferases (OMTs) are necessary for the biosynthesis of methylated PECs, but there is little known about OMTs in Aquilaria sinensis. In this study, we identified 29 OMT genes from the A. sinensis genome. Expression analysis showed they were differentially expressed in different tissues and responded to drill wounding. Comprehensive analysis of the gene expression and methylated PEC content revealed that AsOMT2, AsOMT8, AsOMT11, AsOMT16, and AsOMT28 could potentially be involved in methylated PECs biosynthesis. In vitro enzyme assays and functional analysis in Nicotiana benthamiana demonstrated that AsOMT11 and AsOMT16 could methylate 6-hydroxy-2-(2-phenylethyl)chromone to form 6-methoxy-2-(2-phenylethyl)chromone. A transient overexpression experiment in the variety 'Qi-Nan' revealed that AsOMT11 and AsOMT16 could significantly promote the accumulation of three major methylated PECs. Our results provide candidate genes for the mass production of methylated PECs using synthetic biology.
Assuntos
Metiltransferases , Proteínas de Plantas , Thymelaeaceae , Thymelaeaceae/genética , Thymelaeaceae/metabolismo , Thymelaeaceae/enzimologia , Metiltransferases/metabolismo , Metiltransferases/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Cromonas/metabolismo , Madeira/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Metilação , Regulação da Expressão Gênica de Plantas , FlavonoidesRESUMO
Lateral Organ Boundaries Domain (LBD) proteins are plant-specific transcription factors playing crucial roles in growth and development. However, the function of LBD proteins in Eucalyptus grandis remains largely unexplored. In this study, LBD genes in E. grandis were identified and characterized using bioinformatics approaches. Gene expression patterns in various tissues and the transcriptional responses of EgLBDs to exogenous hormones were determined by qRT-PCR. Functions of the selected EgLBDs were studied by ectopically overexpressing in a hybrid poplar (Populus alba × Populus glandulosa). Expression levels of genes in the transgenic plants were investigated by RNA-seq. Our results showed that there were forty-six EgLBD members in the E. grandis genome and three EgLBDs displayed xylem- (EgLBD29) or phloem-preferential expression (EgLBD22 and EgLBD37). Confocal microscopy indicated that EgLBD22, EgLBD29 and EgLBD37 were localized to the nucleus. Furthermore, we found that EgLBD22, EgLBD29 and EgLBD37 were responsive to the treatments of indol-3-acetic acid and gibberellic acid. More importantly, we demonstrated EgLBDs exerted different influences on secondary growth. Namely, 35S::EgLBD37 led to significantly increased secondary xylem, 35S::EgLBD29 led to greatly increased phloem fibre production, and 35S::EgLBD22 showed no obvious effects. We revealed that key genes related to gibberellin, ethylene and auxin signalling pathway as well as cell expansion were significantly up- or down-regulated in transgenic plants. Our new findings suggest that LBD genes in E. grandis play important roles in secondary growth. This provides new mechanisms to increase wood or fibre production.
Assuntos
Eucalyptus/crescimento & desenvolvimento , Eucalyptus/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Biologia Computacional , Eucalyptus/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Genoma de Planta/genética , Giberelinas/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Xilema/genética , Xilema/crescimento & desenvolvimentoRESUMO
Soil salinization is a matter of concern worldwide. It can eventually lead to the desertification of land and severely damage local agricultural production and the ecological environment. Betula halophila is a tree with high salt tolerance, so it is of importance to understand and discover the salt responsive genes of B. halophila for breeding salinity resistant varieties of trees. However, there is no report on the transcriptome in response to salt stress in B. halophila. Using Illumina sequencing platform, approximately 460 M raw reads were generated and assembled into 117,091 unigenes. Among these unigenes, 64,551 unigenes (55.12%) were annotated with gene descriptions, while the other 44.88% were unknown. 168 up-regulated genes and 351 down-regulated genes were identified, respectively. These Differentially Expressed Genes (DEGs) involved in multiple pathways including the Salt Overly Sensitive (SOS) pathway, ion transport and uptake, antioxidant enzyme, ABA signal pathway and so on. The gene ontology (GO) enrichments suggested that the DEGs were mainly involved in a plant-type cell wall organization biological process, cell wall cellular component, and structural constituent of cell wall molecular function. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment showed that the top-four enriched pathways were 'Fatty acid elongation', 'Ribosome', 'Sphingolipid metabolism' and 'Flavonoid biosynthesis'. The expression patterns of sixteen DEGs were analyzed by qRT-PCR to verify the RNA-seq data. Among them, the transcription factor AT-Hook Motif Nuclear Localized gene and dehydrins might play an important role in response to salt stress in B. halophila. Our results provide an important gene resource to breed salt tolerant plants and useful information for further elucidation of the molecular mechanism of salt tolerance in B. halophila.
Assuntos
Betula , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/fisiologia , Estresse Salino/fisiologia , Plantas Tolerantes a Sal , Betula/genética , Betula/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Plantas Tolerantes a Sal/genética , Plantas Tolerantes a Sal/metabolismoRESUMO
BACKGROUND: WRKY proteins comprise a large family of transcription factors and play important regulatory roles in plant development and defense response. The WRKY gene family in Salvia miltiorrhiza has not been characterized. RESULTS: A total of 61 SmWRKYs were cloned from S. miltiorrhiza. Multiple sequence alignment showed that SmWRKYs could be classified into 3 groups and 8 subgroups. Sequence features, the WRKY domain and other motifs of SmWRKYs are largely conserved with Arabidopsis AtWRKYs. Each group of WRKY domains contains characteristic conserved sequences, and group-specific motifs might attribute to functional divergence of WRKYs. A total of 17 pairs of orthologous SmWRKY and AtWRKY genes and 21 pairs of paralogous SmWRKY genes were identified. Maximum likelihood analysis showed that SmWRKYs had undergone strong selective pressure for adaptive evolution. Functional divergence analysis suggested that the SmWRKY subgroup genes and many paralogous SmWRKY gene pairs were divergent in functions. Various critical amino acids contributed to functional divergence among subgroups were detected. Of the 61 SmWRKYs, 22, 13, 4 and 1 were predominantly expressed in roots, stems, leaves, and flowers, respectively. The other 21 were mainly expressed in at least two tissues analyzed. In S. miltiorrhiza roots treated with MeJA, significant changes of gene expression were observed for 49 SmWRKYs, of which 26 were up-regulated, 18 were down-regulated, while the other 5 were either up-regulated or down-regulated at different time-points of treatment. Analysis of published RNA-seq data showed that 42 of the 61 identified SmWRKYs were yeast extract and Ag(+)-responsive. Through a systematic analysis, SmWRKYs potentially involved in tanshinone biosynthesis were predicted. CONCLUSION: These results provide insights into functional conservation and diversification of SmWRKYs and are useful information for further elucidating SmWRKY functions.
Assuntos
Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Proteínas de Plantas/metabolismo , Salvia miltiorrhiza/genética , Fatores de Transcrição/metabolismo , Acetatos/farmacologia , Sequência de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/classificação , Clonagem Molecular , Ciclopentanos/farmacologia , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Dados de Sequência Molecular , Oxilipinas/farmacologia , Filogenia , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Estrutura Terciária de Proteína , Salvia miltiorrhiza/metabolismo , Alinhamento de Sequência , Prata/farmacologia , Fatores de Transcrição/química , Fatores de Transcrição/classificaçãoRESUMO
MAIN CONCLUSION: Identification and characterization of 5,446 mlncRNAs from Salvia miltiorrhiza showed that the majority of identified mlncRNAs were stress responsive, providing a framework for elucidating mlncRNA functions in S. miltiorrhiza. mRNA-like noncoding RNAs (mlncRNAs) are transcribed by RNA polymerase II and are polyadenylated, capped and spliced. They play important roles in plant development and defense responses. However, there is no information available for mlncRNAs in Salvia miltiorrhiza Bunge, the first Chinese medicinal material entering the international market. To perform a transcriptome-wide identification of S. miltiorrhiza mlncRNAs, we assembled over 8 million RNA-seq reads from GenBank database and 5,624 ESTs from PlantGDB into 44422 unigenes. Using a computational identification pipeline, we identified 5446 S. miltiorrhiza mlncRNA candidates from the assembled unigenes. Of the 5446 mlncRNAs, 2 are primary transcripts of conserved miRNAs, and 2030 can be grouped into 470 families with at least two members in a family. Quantitative real-time PCR analysis of mlncRNAs with at least 900 nt showed that the majority were differentially expressed in roots, stems, leaves and flowers and responsive to methyl jasmonate (MeJA) treatment in S. miltiorrhiza. Analysis of published RNA-seq data showed that a total of 3,044 mlncRNAs were expressed in hairy roots of S. miltiorrhiza and the expression of 1,904 of the 3,044 mlncRNAs was altered by yeast extract and Ag(+) treatment. The results indicate that the majority of mlncRNAs are involved in plant response to stress. This study provides a framework for understanding the roles of mlncRNAs in S. miltiorrhiza.
Assuntos
RNA Mensageiro/genética , RNA de Plantas/genética , RNA não Traduzido/genética , Salvia miltiorrhiza/genética , TranscriptomaRESUMO
SQUAMOSA promoter binding protein-likes (SPLs) are plant-specific transcription factors playing vital regulatory roles in plant growth and development. There is no information about SPLs in Salvia miltiorrhiza (Danshen), a significant medicinal plant widely used in Traditional Chinese medicine (TCM) for >1,700 years and an emerging model plant for TCM studies. Through genome-wide identification and subsequent molecular cloning, we identified a total 15 SmSPLs with divergent sequence features, gene structures, and motifs. Comparative analysis showed sequence conservation between SmSPLs and their Arabidopsis counterparts. A phylogenetic tree clusters SmSPLs into six groups. Many of the motifs identified commonly exist in a group/subgroup, implying their functional redundancy. Eight SmSPLs were predicted and experimentally validated to be targets of miR156/157. SmSPLs were differentially expressed in various tissues of S. milltiorrhiza. The expression of miR156/157-targeted SmSPLs was increased with the maturation of S. miltiorrhiza, whereas the expression of miR156/157 was decreased, confirming the regulatory roles of miR156/157 in SmSPLs and suggesting the functions of SmSPLs in S. miltiorrhiza development. The expression of miR156/157 was negatively correlated with miR172 during the maturation of S. miltiorrhiza. The results indicate the significance and complexity of SmSPL-, miR156-, and miR172-mediated regulation of developmental timing in S. miltiorrhiza.
Assuntos
Genes de Plantas/genética , Genoma de Planta/genética , Família Multigênica , Salvia miltiorrhiza/genética , Motivos de Aminoácidos , Sequência de Aminoácidos , Arabidopsis/genética , Clonagem Molecular , Sequência Consenso , Sequência Conservada/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , MicroRNAs/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Ligação Proteica/genética , Estrutura Terciária de Proteína , Reprodutibilidade dos Testes , Análise de Sequência de DNARESUMO
BACKGROUND: Argonaute (AGO) is the core component of RNA-induced silencing complex. The AGO gene family has been analyzed in various plant species; however, there is no report about AGOs in the well-known Traditional Chinese Medicine (TCM) plant, Salvia miltiorrhiza. RESULTS: Through a genome-wide analysis, we identified ten SmAGO genes in S. miltiorrhiza. Full-length cDNAs of all SmAGOs were subsequently cloned and sequenced. These SmAGOs were characterized using a comprehensive approach. Sequence features, gene structures and conserved domains were analyzed by the comparison of SmAGOs and AtAGOs. Phylogenetic relationships among AGO proteins from S. miltiorrhiza, Arabidopsis and rice were revealed. The expression levels of SmAGO genes in various tissues of S. miltiorrhiza were investigated. The results implied that some SmAGOs, such as SmAGO1, SmAGO2, SmAGO3, SmAGO7 and SmAGO10, probably played similar roles as their counterparts in Arabidopsis; whereas the others could be more species-specialized. It suggests the conservation and diversity of AGOs in plants. Additionally, we identified a total of 24 hairpin structures, representing six miRNA gene families, to be miRNA precursors. Using the modified 5'-RACE method, we confirmed that SmAGO1 and SmAGO2 were targeted by S. miltiorrhiza miR168a/b and miR403, respectively. It suggests the conservation of AGO1-miR168 and AGO2-miR403 regulatory modules in S. miltiorrhiza and Arabidopsis. CONCLUSIONS: This is the first attempt to explore SmAGOs and miRNAs in S. miltiorrhiza. The results provide useful information for further elucidation of gene silencing pathways in S. miltiorrhiza.
Assuntos
Proteínas Argonautas/genética , Perfilação da Expressão Gênica , Genômica , Salvia miltiorrhiza/enzimologia , Salvia miltiorrhiza/genética , Proteínas Argonautas/química , Sequência de Bases , Clonagem Molecular , Sequência Conservada , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Dados de Sequência Molecular , Filogenia , Plantas Medicinais/enzimologia , Plantas Medicinais/genética , Estrutura Terciária de Proteína , Análise de SequênciaRESUMO
Salvia miltiorrhiza Bunge is a well-known material of traditional Chinese medicine. Hydrophilic phenolic acids, such as rosmarinic acid and salvianolic acid B, are a group of pharmaceutically important compounds in S. miltiorrhiza. The biosynthesis of rosmarinic acid requires the coordination of the phenylpropanoid pathway and the tyrosine-derived pathway. Phenylalanine ammonia-lyase (PAL) is the first key enzyme of the phenylpropanoid pathway. Systematic analysis of the SmPAL gene family has not been carried out. We report here the identification of three SmPALs through searching the recently obtained working draft of the S. miltiorrhiza genome and full-length cDNA cloning. Bioinformatic and phylogenetic analyses showed that SmPAL1 and SmPAL3 clustered in a sub-clade of dicot PALs, whereas SmPAL2 fell into the other one. Some important cis-elements were conserved in three SmPAL promoters, whereas the others were not. SmPAL1 and SmPAL3 were highly expressed in roots and leaves of S. miltiorrhiza, but SmPAL2 were predominately expressed in stems and flowers. It indicates that SmPAL1 and SmPAL3 function redundantly in rosmarinic acid biosynthesis. All SmPALs were induced in roots treated with PEG and MeJA, but the time and degree of responses were different, suggesting the complexity of SmPAL-associated metabolic network in S. miltiorrhiza. This is the first comprehensive study dedicated to SmPAL gene family characterization. The results provide a basis for elucidating the role of SmPAL genes in the biosynthesis of bioactive compounds.
Assuntos
Família Multigênica , Fenilalanina Amônia-Liase/genética , Salvia miltiorrhiza/genética , Região 5'-Flanqueadora , Sequência de Aminoácidos , Vias Biossintéticas , Cinamatos/metabolismo , Clonagem Molecular , DNA Complementar/genética , Depsídeos/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Dados de Sequência Molecular , Especificidade de Órgãos/genética , Fenilalanina Amônia-Liase/metabolismo , Filogenia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Salvia miltiorrhiza/enzimologia , Alinhamento de Sequência , Ácido RosmarínicoRESUMO
Argonaute 1 (AGO1) is a core component of the RNA-induced silencing complex (RISC) which plays a crucial role in small RNA-mediated gene silencing. AGO1 gene has been characterized in various plants, such as Arabidopsis and rice. However, there is no information about AGO1 in the medicinal plant species, Panax ginseng. Using the rapid amplification of cDNA ends technology (RACE), we cloned full-length PgAGO1 cDNA from Panax ginseng. It is 3 776 bp in length, including 204 bp of 5' UTR, 254 bp of 3' UTR, and 3 318 bp of ORF encoding 1106 amino acids. The molecular weight (MW) and theroretical isoelectric point (pI) of the deduced PgAGO1 protein is 122.22 kDa and 9.71, respectively. PgAGO1 shares 91.72% similarity with Arabidopsis AtAGO1 and contains three consered domains, including DUF1785, PAZ and Piwi, suggesting it is an authentic AGO. PgAGO1 was expressed in all of the tissues analyzed with the highest level in flowers and the lowest level in roots. The results provide useful information for further elucidating the function of AGO1 in Panax ginseng.
Assuntos
Proteínas Argonautas/genética , Genes de Plantas , Panax/genética , Sequência de Aminoácidos , Clonagem Molecular , DNA Complementar/genética , DNA de Plantas/genética , Dados de Sequência Molecular , Plantas Medicinais/genética , Alinhamento de SequênciaRESUMO
The conversion of lignocellulosic feedstocks to fermentable sugar for biofuel production is inefficient, and most strategies to enhance efficiency directly target lignin biosynthesis, with associated negative growth impacts. Here we demonstrate, for both laboratory- and field-grown plants, that expression of Pag-miR408 in poplar (Populus alba × P. glandulosa) significantly enhances saccharification, with no requirement for acid-pretreatment, while promoting plant growth. The overexpression plants show increased accessibility of cell walls to cellulase and scaffoldin cellulose-binding modules. Conversely, Pag-miR408 loss-of-function poplar shows decreased cell wall accessibility. Overexpression of Pag-miR408 targets three Pag-LACCASES, delays lignification, and modestly reduces lignin content, S/G ratio and degree of lignin polymerization. Meanwhile, the LACCASE loss of function mutants exhibit significantly increased growth and cell wall accessibility in xylem. Our study shows how Pag-miR408 regulates lignification and secondary growth, and suggest an effective approach towards enhancing biomass yield and saccharification efficiency in a major bioenergy crop.
Assuntos
MicroRNAs , Populus , Lignina/metabolismo , Plantas Geneticamente Modificadas/genética , MicroRNAs/genética , Biomassa , Populus/metabolismoRESUMO
N6-methyladenosine (m6A) RNA modification is a conserved mechanism to regulate gene expression that plays vital roles in the development of plants. However, the m6A RNA modification in forest trees remains limited. Here, we performed a complete analysis of m6A writers, erasers and readers in Poplar 84K, including gene location, gene structures, conserved motifs, phylogenetic relationships, promoter analysis, expression profiles and the homology modeling. We have identified 61 m6A pathway genes in Poplar 84K (Populus alba × Populus glandulosa), including 14 m6A writers, 14 m6A erasers and 33 m6A readers. Phylogenetic analysis indicated that the m6A writers and erasers were clustered into four groups and m6A readers were clustered into two groups. Promoter analysis showed that m6A pathway genes were mainly responsive to low oxygen followed by ABA and ethylene. The expression of the identified m6A pathway genes showed tissue-specific expression patterns in leaves, xylem, phloem and roots. Moreover, 17 genes were significantly up-regulated and 13 genes were significantly down-regulated in poplar overexpressing the transcription factor LBD15. Homology modeling and molecular docking results suggested that PagFIP37b was most likely to be regulated by LBD15, and the qPCRshowed that PagFIP37b were up-regulated in the LBD15-oe plants. The results provide insights that aid in the future elucidation of the functions of these m6A pathway genes and the epigenetic regulation mechanism of these genes in Poplar 84K.
Assuntos
Populus , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Simulação de Acoplamento Molecular , Filogenia , Populus/metabolismo , RNA/metabolismoRESUMO
BACKGROUND: Taxus is a valuable woody species with important medicinal value. The bark of Taxus can produce taxol, a natural antineoplastic drug that is widely used in the treatment of breast, ovarian and lung cancers. However, the low content of taxol in the bark of Taxus can not meet the growing clinical demands, so the current research aims at finding ways to increase taxol production. OBJECTIVE: In this review, the research progress of taxol including the factors affecting the taxol content, biosynthesis pathway of taxol, production of taxol in vitro and the application of multi-omics approaches in Taxus as well as future research prospects will be discussed. RESULTS: The taxol content is not only dependent on the species, age and tissues but is also affected by light, moisture levels, temperature, soil fertility and microbes. Most of the enzymes in the taxol biosynthesis pathway have been identified and characterized. Total chemical synthesis, semi-synthesis, plant cell culture and biosynthesis in endophytic fungi have been explored to product taxol. Multi-omics have been used to study Taxus and taxol. CONCLUSION: Further efforts in the identification of unknown enzymes in the taxol biosynthesis pathway, establishment of the genetic transformation system in Taxus and the regulatory mechanism of taxol biosynthesis and Taxus cell growth will play a significant role in improving the yield of taxol in Taxus cells and plants.
Assuntos
Antineoplásicos Fitogênicos/biossíntese , Pesquisa Biomédica/tendências , Paclitaxel/biossíntese , Taxus , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Paclitaxel/química , Paclitaxel/uso terapêutico , Taxus/microbiologiaRESUMO
The MYB transcription factor family is one of the largest gene families playing regulatory roles in plant growth and development. The MYB family has been studied in a variety of plant species but has not been reported in Taxus chinensis. Here we identified 72 putative R2R3-MYB genes in T. chinensis using a comprehensive analysis. Sequence features, conversed domains and motifs were characterized. The phylogenetic analysis showed TcMYBs and AtMYBs were clustered into 36 subgroups, of which 24 subgroups included members from T. chinensis and Arabidopsis thaliana, while 12 subgroups were specific to one species. This suggests the conservation and specificity in structure and function of plant R2R3-MYBs. The expression of TcMYBs in various tissues and different ages of xylem were investigated. Additionally, miRNA-mediated posttranscriptional regulation analysis revealed that TcMYBs were the targets of miR858, miR159 and miR828, suggesting the posttranscriptional regulation of MYBs is highly conserved in plants. The results provide a basis for further study the role of TcMYBs in the regulation of secondary metabolites of T. chinensis.
RESUMO
Taxus chinensis is a precious woody species with significant economic value. Anthocyanin as flavonoid derivatives plays a crucial role in plant biology and human health. However, the genes involved in anthocyanin biosynthesis have not been identified in T. chinensis. In this study, twenty-five genes involved in anthocyanin biosynthesis were identified, including chalcone synthase, chalcone isomerase, flavanone 3-hydroxylase, anthocyanidin synthase, flavonoid 3'-hydroxylase, flavonoid 3',5'-hydroxylase, dihydroflavonol 4-reductase, anthocyanidin reductase, and leucoanthocyanidin reductase. The conserved domains and phylogenetic relationships of these genes were characterized. The expression levels of these genes in different tissues and different ages of xylem were investigated. Additionally, the anthocyanin accumulation in xylem of different ages of T. chinensis was measured. The results showed the anthocyanin accumulation was correlated with the expression levels of dihydroflavonol 4-reductase, anthocyanidin synthase, flavonoid 3'-hydroxylase, and flavonoid 3',5'-hydroxylase. Our results provide a basis for studying the regulation of the biosynthetic pathway for anthocyanins and wood color formation in T. chinensis.
Assuntos
Antocianinas/biossíntese , Vias Biossintéticas , Taxus/metabolismo , Xilema/metabolismo , Evolução Molecular , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Taxus/genética , Distribuição TecidualRESUMO
Taxus chinensis is a well-known gymnosperm with great ornamental and medicinal value. Its purple red brown heartwood (HW) has many attributes such as straight texture, high density, mechanical strength, rich elasticity and corrosion resistance that is highly prized commercially. T. chinensis sapwood (SW), in comparison, lacks these important traits. At present, little is known about the differences of metabolites between the SW and HW in T. chinensis. Widely targeted metabolic profiling was performed to analyze the metabolic profiles of HW and SW in T. chinensis using Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-EI-MS). A total of 607 metabolites were detected in HW and SW. Among them, 146 metabolites were significantly higher, and 167 metabolites significantly lower, in HW as compared to SW. These differential metabolites were mainly involved in metabolic pathways and biosynthesis of secondary metabolites, such as flavonoids, flavone and flavonol, phenylpropanoids and antibiotics. Moreover, 71 flavonoids and isoflavones were found to be significantly different between HW and SW. Our results show the difference of components between the HW and SW, which has potential significance to further elucidate the mechanism of HW color formation. The results will provide insight into the metabolites associated with wood color formation and useful information for understanding the metabolites associated with wood quality.
Assuntos
Metabolômica/métodos , Taxus/metabolismo , Madeira/metabolismo , Cromatografia Líquida , Flavonoides/análise , Isoflavonas/análise , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Poplar 84K (Populus alba x P. tremula var. glandulosa) is a fast-growing poplar hybrid. Originated in South Korea, this hybrid has been extensively cultivated in northern China. Due to the economic and ecological importance of this hybrid and high transformability, we now report the de novo sequencing and assembly of a male individual of poplar 84K using PacBio and Hi-C technologies. The final reference nuclear genome (747.5 Mb) has a contig N50 size of 1.99 Mb and a scaffold N50 size of 19.6 Mb. Complete chloroplast and mitochondrial genomes were also assembled from the sequencing data. Based on similarities to the genomes of P. alba var. pyramidalis and P. tremula, we were able to identify two subgenomes, representing 356 Mb from P. alba (subgenome A) and 354 Mb from P. tremula var. glandulosa (subgenome G). The phased assembly allowed us to detect the transcriptional bias between the two subgenomes, and we found that the subgenome from P. tremula displayed dominant expression in both 84K and another widely used hybrid, P. tremula x P. alba. This high-quality poplar 84K genome will be a valuable resource for poplar breeding and for molecular biology studies.
Assuntos
Genoma de Cloroplastos , Genoma Mitocondrial , Genoma de Planta , Populus/genética , Análise de Sequência de DNA , Sequência de Bases , Núcleo Celular , DNA de PlantasRESUMO
SQUAMOSA Promoter-Binding Protein-Likes (SPLs) are plant specific transcription factors playing important roles in plant growth and development. The SPL gene family has been studied in various plant species; however, there is no report about SPLs in Zizyphus jujuba. In this study, we identified 18 putative ZjSPL genes in Z. jujuba using a genome-wide analysis. Sequence features, gene structures, conserved domains and motifs were analyzed. The phylogenetic relationships of SPLs in Z. jujuba and A. thaliana were revealed. A total of 5 pairs of ZjSPLs were identified, suggesting the importance of gene duplication in SPL gene expansion in Z. jujuba. In addition, 11 of the 18 ZjSPLs, belonging to G1, G2 and G5 subgroups, were found to be targets of miR156, suggesting the conservation of miR156-mediated posttranscriptional regulation in plants. Expression analysis revealed that eight ZjSPL genes were responsive to the infection of witches'-broom phytoplasma. Our results provide a basis for the further elucidation of the biological function of ZjSPLs and their regulation in witches'-broom disease.
Assuntos
Proteínas de Ligação a DNA/genética , Genoma de Planta , Proteínas de Plantas/genética , Rhamnaceae/genética , Proteínas de Ligação a DNA/química , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Phytoplasma/patogenicidade , Imunidade Vegetal/genética , Proteínas de Plantas/química , Domínios Proteicos , Rhamnaceae/classificação , Rhamnaceae/imunologiaRESUMO
Salvia miltiorrhiza is a well-known material of traditional Chinese medicine. Understanding the regulatory mechanisms of phenolic acid biosynthesis and metabolism are important for S. miltiorrhiza quality improvement. We report here that S. miltiorrhiza contains 19 polyphenol oxidases (PPOs), forming the largest PPO gene family in plant species to our knowledge. Analysis of gene structures and sequence features revealed the conservation and divergence of SmPPOs. SmPPOs were differentially expressed in plant tissues and eight of them were predominantly expressed in phloem and xylem, indicating that some SmPPOs are functionally redundant, whereas the others are associated with different physiological processes. Expression patterns of eighteen SmPPOs were significantly altered under MeJA treatment, and twelve were yeast extract and Ag+-responsive, suggesting the majority of SmPPOs are stress-responsive. Analysis of high-throughput small RNA sequences and degradome data showed that miR1444-mediated regulation of PPOs existing in P. trichocarpa is absent from S. miltiorrhiza. Instead, a subset of SmPPOs was posttranscriptionally regulated by a novel miRNA, termed Smi-miR12112. It indicates the specificity and significance of miRNA-mediated regulation of PPOs. The results shed light on the regulation of SmPPO expression and suggest the complexity of SmPPO-associated phenolic acid biosynthesis and metabolism.
Assuntos
Catecol Oxidase/genética , Regulação da Expressão Gênica de Plantas , MicroRNAs/genética , Família Multigênica , Salvia miltiorrhiza/enzimologia , Salvia miltiorrhiza/genética , Transcrição Gênica , Acetatos/farmacologia , Sequência de Aminoácidos , Sequência de Bases , Catecol Oxidase/química , Catecol Oxidase/metabolismo , Clonagem Molecular , Sequência Conservada/genética , Ciclopentanos/farmacologia , Éxons/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Variação Genética , Íntrons/genética , MicroRNAs/metabolismo , Oxilipinas/farmacologia , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/metabolismo , Salvia miltiorrhiza/efeitos dos fármacos , Especificidade da Espécie , Transcrição Gênica/efeitos dos fármacosRESUMO
Small RNA-mediated gene silencing is a vital regulatory mechanism in eukaryotes that requires ARGONAUTE (AGO) proteins. Salvia miltiorrhiza is a well-known traditional Chinese medicinal plant. Therefore, it is important to characterize S. miltiorrhiza AGO family genes as they may be involved in multiple metabolic pathways. This chapter introduces the detailed protocol for SmAGO gene prediction and molecular cloning. In addition, an Agrobacterium-mediated genetic transformation method for S. miltiorrhiza is presented. These methodologies can be used to functionally study SmAGO genes as well as other genes of interest in S. miltiorrhiza.
Assuntos
Proteínas Argonautas/genética , Clonagem Molecular/métodos , Proteínas de Plantas/genética , Salvia miltiorrhiza/genética , Transformação Genética , Agrobacterium/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Reação em Cadeia da Polimerase/métodos , Salvia miltiorrhiza/crescimento & desenvolvimentoRESUMO
MicroRNAs (miRNAs) play an important role in responding to biotic and abiotic stresses in plants. Jujube witches'-broom a phytoplasma disease of Ziziphus jujuba is prevalent in China and is a serious problem to the industry. However, the molecular mechanism of the disease is poorly understood. In this study, genome-wide identification and analysis of microRNAs in response to witches'-broom was performed. A total of 85 conserved miRNA unique sequences belonging to 32 miRNA families and 24 novel miRNA unique sequences, including their complementary miRNA* strands were identified from small RNA libraries derived from a uninfected and witches'-broom infected Z. jujuba plant. Differentially expressed miRNAs associated with Jujube witches'-broom disease were investigated between the two libraries, and 12 up-regulated miRNAs and 10 down- regulated miRNAs identified with more than 2 fold changes. Additionally, 40 target genes of 85 conserved miRNAs and 49 target genes of 24 novel miRNAs were predicted and their putative functions assigned. Using the modified 5'-RACE method, we confirmed that SPL and MYB were cleaved by miR156 and miR159, respectively. Our results provide insight into the molecular mechanisms of witches'-broom disease in Z. jujuba.