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Stress tolerance in apple (Malus domestica) can be improved by grafting to a stress-tolerant rootstock, such as 'SH6' (Malus honanensis × M. domestica 'Ralls Genet'). However, the mechanisms of stress tolerance in this rootstock are unclear. In Arabidopsis (Arabidopsis thaliana), the transcription factor ZINC FINGER OF ARABIDOPSIS THALIANA 10 is a key component of plant tolerance to multiple abiotic stresses and positively regulates antioxidant enzymes. However, how reactive oxygen species are eliminated upon activation of ZINC FINGER OF ARABIDOPSIS THALIANA 10 in response to abiotic stress remains elusive. Here, we report that MhZAT10 in the rootstock SH6 directly activates the transcription of three genes encoding the antioxidant enzymes MANGANESE SUPEROXIDE DISMUTASE 1 (MhMSD1), ASCORBATE PEROXIDASE 3A (MhAPX3a) and CATALASE 1 (MhCAT1) by binding to their promoters. Heterologous expression in Arabidopsis protoplasts showed that MhMSD1, MhAPX3a and MhCAT1 localize in multiple subcellular compartments. Overexpressing MhMSD1, MhAPX3a or MhCAT1 in SH6 fruit calli resulted in higher superoxide dismutase, ascorbate peroxidase and catalase enzyme activities in their respective overexpressing calli than in those overexpressing MhZAT10. Notably, the calli overexpressing MhZAT10 exhibited better growth and lower reactive oxygen species levels under simulated osmotic stress. Apple SH6 plants overexpressing MhZAT10 in their roots via Agrobacterium rhizogenes-mediated transformation also showed enhanced tolerance to osmotic stress, with higher leaf photosynthetic capacity, relative water content in roots and antioxidant enzyme activity, as well as less reactive oxygen species accumulation. Overall, our study demonstrates that the transcription factor MhZAT10 synergistically regulates the transcription of multiple antioxidant-related genes and elevates reactive oxygen species detoxification.
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Antioxidantes , Malus , Proteínas de Plantas , Fatores de Transcrição , Malus/genética , Malus/metabolismo , Malus/fisiologia , Antioxidantes/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Ascorbato Peroxidases/metabolismo , Ascorbato Peroxidases/genética , Espécies Reativas de Oxigênio/metabolismo , Catalase/metabolismo , Catalase/genéticaRESUMO
Drought seriously affects the growth and development of plants. MiR159 is a highly conserved and abundant microRNA family that plays a crucial role in plant growth and stress responses. However, studies of its function in woody plants are still lacking. Here, the expression of miR159a was significantly upregulated after drought treatment in poplar, and the overexpression of miR159a (OX159a) significantly reduced the open area of the stomata and improved water-use efficiency in poplar. After drought treatment, OX159a lines had better scavenging ability of reactive oxygen species and damage of the membrane system was less than that in wild-type lines. MYB was the target gene of miR159a, as verified by psRNATarget prediction, RT-qPCR, degradome sequencing, and 5' rapid amplification of cDNA ends (5' RACE). Additionally, miR159a-short tandem target mimic suppression (STTM) poplar lines showed increased sensitivity to drought stress. Transcriptomic analysis comparing OX159a lines with wild-type lines revealed upregulation of a series of genes related to response to water deprivation and metabolite synthesis. Moreover, drought-responsive miR172d and miR398 were significantly upregulated and downregulated respectively in OX159a lines. This investigation demonstrated that miR159a played a key role in the tolerance of poplar to drought by reducing stomata open area, increasing the number and total area of xylem vessels, and enhancing water-use efficiency, and provided new insights into the role of plant miR159a and crucial candidate genes for the molecular breeding of trees with tolerance to drought stress.
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Trees are inevitably attacked by different kinds of pathogens in their life. However, little is known about the regulatory factors in poplar response to different pathogen infections. MicroRNA159 (miR159) is a highly conserved microRNA (miRNA) in plants and regulates plant development and stress responses. Here, transgenic poplar overexpressing pto-miR159a (OX-159) showed antagonistic regulation mode to poplar stem disease caused by fungi Cytospora chrysosperma and bacteria Lonsdalea populi. OX-159 lines exhibited a higher susceptibility after inoculation with bacterium L. populi, whereas enhanced disease resistance to necrotrophic fungi C. chrysosperma compared with wild-type (WT) poplars. Intriguingly, further disease assay found that OX159 line rendered the poplar susceptible to hemi-biotrophic fungi Colletotrichum gloeosporioide, exhibiting larger necrosis and lower ROS accumulation than WT lines. Transcriptome analyses revealed that more down-regulated differentially expressed genes with disease-resistant domains in OX-159 line compared with WT line. Moreover, the central mediator NPR1 of salicylic acid (SA) pathway showed a decrease in expression level, while jasmonic acid/ethylene (JA/ET) signal pathway marker genes ERF, as well as PR3, MPK3, and MPK6 genes showed an increase level in OX159-2 and OX159-5 compared with WT lines. Further spatio-temporal expression analysis revealed JA/ET signaling was involved in the dynamic response process to C. gloeosporioides in WT and OX159 lines. These results demonstrate that overexpression of pto-miR159a resulted in the crosstalk changes of the downstream hub genes, thereby controlling the disease resistance of poplars, which provides clues for understanding pto-miR159a role in coordinating poplar-pathogen interactions.
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Resistência à Doença , MicroRNAs , Resistência à Doença/genética , Transdução de Sinais , Perfilação da Expressão Gênica , MicroRNAs/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Ácido Salicílico/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Drought and cold stresses seriously affect tree growth and fruit yield during apple (Malus domestica) production, with combined stress causing injury such as shoot shriveling. However, the molecular mechanism underlying crosstalk between responses to drought and cold stress remains to be clarified. In this study, we characterized the zinc finger transcription factor ZINC FINGER OF ARABIDOPSIS THALIANA 10 (ZAT10) through comparative analysis of shoot-shriveling tolerance between tolerant and sensitive apple rootstocks. MhZAT10 responded to both drought and cold stresses. Heterologous expression of MhZAT10 in the sensitive rootstock 'G935' from domesticated apple (Malus domestica) promoted shoot-shriveling tolerance, while silencing of MhZAT10 expression in the tolerant rootstock 'SH6' of Malus honanensis reduced stress tolerance. We determined that the apple transcription factor DEHYDRATION RESPONSE ELEMENT-BINDING PROTEIN 2A (DREB2A) is a direct regulator activating the expression of MhZAT10 in response to drought stress. Apple plants overexpressing both MhDREB2A and MhZAT10 genes exhibited enhanced tolerance to drought and cold stress, while plants overexpressing MhDREB2A but with silenced expression of MhZAT10 showed reduced tolerance, suggesting a critical role of MhDREB2A-MhZAT10 in the crosstalk between drought and cold stress responses. We further identified drought-tolerant MhWRKY31 and cold-tolerant MhMYB88 and MhMYB124 as downstream regulatory target genes of MhZAT10. Our findings reveal a MhDREB2A-MhZAT10 module involved in crosstalk between drought and cold stress responses, which may have applications in apple rootstock breeding programs aimed at developing shoot-shriveling tolerance.
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Malus , Malus/metabolismo , Resposta ao Choque Frio/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Secas , Estresse Fisiológico/genética , Proteínas de Plantas/metabolismo , Melhoramento Vegetal , Plantas Geneticamente Modificadas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
Potassium (K) is one of the most important macronutrients for plant development and growth. The influence mechanism of different potassium stresses on the molecular regulation and metabolites of apple remains largely unknown. In this research, physiological, transcriptome, and metabolite analyses were compared under different K conditions in apple seedlings. The results showed that K deficiency and excess conditions influenced apple phenotypic characteristics, soil plant analytical development (SPAD) values, and photosynthesis. Hydrogen peroxide (H2O2) content, peroxidase (POD) activity, catalase (CAT) activity, abscisic acid (ABA) content, and indoleacetic acid (IAA) content were regulated by different K stresses. Transcriptome analysis indicated that there were 2,409 and 778 differentially expressed genes (DEGs) in apple leaves and roots under K deficiency conditions in addition to 1,393 and 1,205 DEGs in apple leaves and roots under potassium excess conditions, respectively. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment showed that the DEGs were involved in flavonoid biosynthesis, photosynthesis, and plant hormone signal transduction metabolite biosynthetic processes in response to different K conditions. There were 527 and 166 differential metabolites (DMAs) in leaves and roots under low-K stress as well as 228 and 150 DMAs in apple leaves and roots under high-K stress, respectively. Apple plants regulate carbon metabolism and the flavonoid pathway to respond to low-K and high-K stresses. This study provides a basis for understanding the metabolic processes underlying different K responses and provides a foundation to improve the utilization efficiency of K in apples.
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Different poplar varieties vary in their tolerance to certain pathogens. However, knowledge about molecular regulation and critical responses of resistant poplars during pathogen infection remains scarce. To investigate adaptive responses to canker disease caused by the bacterium Lonsdalea populi, we screened three poplar varieties with contrasting tolerance, including Populus deltoides. 'Zhonglin 2025' (2025), Populus × Euramericana. '74/76' (107) and Populus tomentosa cv 'henan' (P. tomentosa). Transcriptomic analysis revealed significant changes in the expression levels of defence-related genes in different poplar varieties in response to infection, which reshaped the PTI and ETI processes. Intriguingly, photosynthesis-related genes were found to be highly expressed in the resistant variety, whereas the opposite was observed in the susceptible variety. Susceptible poplars maintained the activation of defence-related genes during early period of onset, which restricted the expression of photosynthesis-related and auxin signal-related genes. Furthermore, combined with metabolomic analysis, differences in the content of antibacterial substances and key differentially expressed genes in phenylpropane and flavonoid biosynthesis pathways were identified. Delayed induction of catechin in the susceptible variety and it's in vitro antibacterial activity were considered to be one of the important reasons for the differences in resistance to L. populi compared with the resistant variety, which is of practical interest for tree breeding. Moreover, the trade-off between growth and defence observed among the three poplar varieties during infection provides new insights into the multilevel regulatory circuits in tree-pathogen interactions.
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MetabolômicaRESUMO
The site of Qujialing experienced a long, sustained process of the development of Neolithic culture in the Jianghan Plain, with a period of some1600 years. Our previous studies based on macrofossil remains and phytoliths revealed that rice (Oryza sativa) from Qujialing was already domesticated, and millet (Setaria italica and Panicum miliaceum) had also been spread into the site since the Youziling Culture period (5800-5100 BP). Nevertheless, no direct evidence has been provided regarding the daily consumed plant foods, especially plant foods obtained by gathering, throughout the site occupation. This paper thus examines pottery sherds (n=41) associated with culinary practices from Qujialing with starch grain analysis. Apart from starch grains from rice and millet, the results indicate that job's tears (Coix lacryma-jobi), lotus roots (Nelumbo nucifera), tubers possibly from Chinese yam (Dioscorea panthainca), acorns (Quercus sp.), and beans (Vigna sp. or/and Vicia sp.) were consumed by the ancient Qujialing people, within job's tears and lotus roots were not discovered before in the macrofossil remains and phytoliths. Combining the starch data and multiple lines of evidence from macrofossil remains and phytoliths, it is suggested that rice was among the most frequently consumed plant foods since the first occupation phase at Qujialing, while acorns could have been gradually replaced by other agricultural products (i.e., rice) and became less important food ingredients, especially when agriculture was more developed in the last occupation phase at Qujialing. These novel findings not only complement our previous research by providing the first line of evidence of paleodiet in the Jianghan Plain from the perspective of starch grain analysis but also delivers a better understanding of the characterized dietary trends and agricultural development in the research region.
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Non-coding RNAs (ncRNAs) play essential roles in plants by modulating the expression of genes at the transcriptional or post-transcriptional level. In recent years, ncRNAs have been recognized as crucial regulators for growth and development in forest trees, and ncRNAs that respond to various abiotic stresses are now under intense study. In this review, we summarized recent advances in the understanding of abiotic stress-responsive microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) in forest trees. Furthermore, we analyzed the intersection of miRNAs, and epigenetic modified ncRNAs of forest trees in response to abiotic stress. In particular, the abiotic stress-related lncRNA/circRNA-miRNA-mRNA regulatory network of forest trees was explored.
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MicroRNAs , RNA Longo não Codificante , Florestas , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Circular/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA não Traduzido/genética , Estresse Fisiológico/genética , Árvores/genética , Árvores/metabolismoRESUMO
The metallic complex is widely used in agricultural applications. Due to the oxidation of the metal and environmental unfriendliness of ligand, maintaining an efficient mineral supply for plants without causing environmental damage is difficult. Herein, an antioxidative trimetallic complex with high stability was synthesized by interacting Ca2+, Fe2+, and Zn2+ with the biocompatible ligands from the Maillard reaction. The composite structure elucidation was carried out by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR). Thermal stability was measured by thermogravimetric (TG). Antioxidative activities were evaluated by ferric reducing antioxidant power and radical scavenging activity assays. The three metals were successfully fabricated on the Maillard reaction products (MRPs) with contents of Ca (9.01%), Fe (8.25%), and Zn (9.67%). Microscopy images revealed that the three metals were uniformly distributed on the MRPs with partial aggregation of <30 nm. FTIR and XPS results revealed that the metals were interacted with MRPs by metal-O and metal-N bonds. TG and antioxidative activity assays showed that the trimetallic complex meets the requirements of thermodynamics and oxidation resistance of horticultural applications. Additionally, the results of the exogenous spraying experiment showed that the trimetallic complex significantly increased the mineral contents of the "Fuji" apple. By treatment with the complex, the concentrations of Ca, Fe, and Zn were increased by 85.4, 532.5, and 931.1% in the leaf; 16.0, 225.2, and 468.6% in the peel; and 117.6, 217.9, and 19.5% in the flesh, respectively. The MRP-based complexes offered a higher growth rate of the mineral content in apples than ones based on sugars or amino acids. The results of the spraying experiment carried out in 2 years show that the method has high reproducibility. This study thus promotes the development of green metallic complexes and expands the scope of agrochemical strategy.
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BACKGROUND: Leaf colour mutations are universally expressed at the seedling stage and are ideal materials for exploring the chlorophyll biosynthesis pathway, carotenoid metabolism and the flavonoid biosynthesis pathway in plants. RESULTS: In this research, we analysed the different degrees of albinism in apple (Malus domestica) seedlings, including white-leaf mutants (WM), piebald leaf mutants (PM), light-green leaf mutants (LM) and normal leaves (NL) using bisulfite sequencing (BS-seq) and RNA sequencing (RNA-seq). There were 61,755, 79,824, and 74,899 differentially methylated regions (DMRs) and 7566, 3660, and 3546 differentially expressed genes (DEGs) identified in the WM/NL, PM/NL and LM/NL comparisons, respectively. CONCLUSION: The analysis of the methylome and transcriptome showed that 9 DMR-associated DEGs were involved in the carotenoid metabolism and flavonoid biosynthesis pathway. The expression of different transcription factors (TFs) may also influence the chlorophyll biosynthesis pathway, carotenoid metabolism and the flavonoid biosynthesis pathway in apple leaf mutants. This study provides a new method for understanding the differences in the formation of apple seedlings with different degrees of albinism.
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Albinismo , Malus , Albinismo/genética , Albinismo/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Epigenoma , Flavonoides/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Malus/genética , Malus/metabolismo , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plântula/genética , Plântula/metabolismo , TranscriptomaRESUMO
The external application of acetic acid (AA) has been shown to improve drought survival in plants, such as Arabidopsis, rice, maize, wheat, rapeseed and cassava, and the application of AA also increased drought tolerance in perennial woody apple (Malus domestica) plants. An understanding of AA-induced drought tolerance in apple plants at the molecular level will contribute to the development of technology that can be used to enhance drought tolerance. In this study, the morphological, physiological and transcriptomic responses to drought stress were analyzed in apple plants after watering without AA (CK), watering with AA (AA), drought treatment (D) and drought treatment with AA (DA). The results suggested that the AA-treated apple plants had a higher tolerance to drought than water-treated plants. Higher levels of chlorophyll and carotenoids were found under the DA conditions than under D stress. The levels of abscisic acid (ABA), jasmonic acid (JA) and methyl jasmonate were increased in AA-treated apple plants. Transcriptomic profiling indicated the key biological pathways involved in metabolic processes, mitogen-activated protein kinase (MAPK) signaling, plant hormone signal transduction and the biosynthesis of secondary metabolites in response to different drought conditions. The 9-cis-epoxycarotenoid dioxygenase, (9S,13S)-cis-oxophytodienoic acid reductase, allene oxide synthase, allene oxide cyclase and lipoxygenase genes participate in the synthase of ABA and JA under drought and AA treatments. Collectively, the results showed that external application of AA enhanced drought tolerance in apple plants by influencing the ABA- and JA-induced MAPK signaling pathways. These data indicated that the application of AA in plants is beneficial for enhancing drought tolerance and decreasing growth inhibition in agricultural fields.
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Arabidopsis , Malus , Ácido Abscísico/metabolismo , Ácido Acético/farmacologia , Arabidopsis/genética , Ciclopentanos , Secas , Regulação da Expressão Gênica de Plantas , Malus/genética , Malus/metabolismo , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oxilipinas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Transdução de Sinais , Estresse Fisiológico/genética , Água/metabolismoRESUMO
Phosphorus (P) is an important element in numerous metabolic reactions and signalling pathways, but the molecular details of these pathways remain largely unknown. In this study, physiological, transcriptome and metabolite analyses of apple leaves and roots were compared under different P conditions. The results showed that different P stresses influenced phenotypic characteristics, soil plant analytical development (SPAD) values and the contents of flavonoids and anthocyanins in apple seedlings. The contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA) and the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), acid phosphatase (ACP) and purple acid phosphatase (PAP) were also affected by different P stresses. In addition, RNA sequencing (RNA-seq) was used to characterize the influence of different P stresses on apple seedlings. Compared with control apple plants, there were 1246 and 1183 differentially expressed genes (DEGs) in leaves and roots under the low-P treatment and 60 and 1030 DEGs in leaves and roots under the high-P treatment, respectively. Gene Ontology (GO) analysis indicated that apple trees might change their responses to metabolic processes, cell proliferation, regulation of biological processes, reactive oxygen species metabolic processes and flavonoid metabolic processes under P stress. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis further indicated that DEGs act on the mitogen-activated protein kinase (MAPK) signalling pathway, flavonoid biosynthesis, phenylpropanoid biosynthesis, and ATP-binding cassette (ABC) transporters. The metabolome analysis revealed that the levels of most amino acids and their derivatives, organic acids and flavonoids in roots treated with low-P stress were higher than those in roots of apple seedlings under control growth conditions. Apple seedlings regulate the flavonoid pathway to respond to different phosphorus environments. The results provide a framework for understanding the metabolic processes underlying different P responses and provide a foundation for improving the utilization efficiency of P in apple trees.
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Malus , Transcriptoma , Antocianinas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Peróxido de Hidrogênio , Malus/genética , Metaboloma , FósforoRESUMO
Plants have evolved diverse molecular mechanisms that enable them to respond to a wide range of pathogens. It has become clear that microRNAs, a class of short single-stranded RNA molecules that regulate gene expression at the transcriptional or post-translational level, play a crucial role in coordinating plant-pathogen interactions. Specifically, miRNAs have been shown to be involved in the regulation of phytohormone signals, reactive oxygen species, and NBS-LRR gene expression, thereby modulating the arms race between hosts and pathogens. Adding another level of complexity, it has recently been shown that specific lncRNAs (ceRNAs) can act as decoys that interact with and modulate the activity of miRNAs. Here we review recent findings regarding the roles of miRNA in plant defense, with a focus on the regulatory modes of miRNAs and their possible applications in breeding pathogen-resistance plants including crops and trees. Special emphasis is placed on discussing the role of miRNA in the arms race between hosts and pathogens, and the interaction between disease-related miRNAs and lncRNAs.
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Regulação da Expressão Gênica de Plantas/imunologia , Interações Hospedeiro-Patógeno/genética , MicroRNAs/genética , Doenças das Plantas/genética , Imunidade Vegetal/genética , Proteínas de Plantas/genética , Plantas/genética , Interações Hospedeiro-Patógeno/imunologia , MicroRNAs/imunologia , Fungos Mitospóricos/genética , Fungos Mitospóricos/crescimento & desenvolvimento , Fungos Mitospóricos/patogenicidade , Melhoramento Vegetal/métodos , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Reguladores de Crescimento de Plantas/imunologia , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/imunologia , Plantas/imunologia , Plantas/microbiologia , RNA Longo não Codificante/genética , RNA Longo não Codificante/imunologia , RNA de Plantas/genética , RNA de Plantas/imunologia , Espécies Reativas de Oxigênio/imunologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de SinaisRESUMO
DNA methylation plays crucial roles in responses to environmental stimuli. Modification of DNA methylation during development and abiotic stress responses has been confirmed in increasing numbers of plants, mainly annual plants. However, the epigenetic regulation mechanism underlying the immune response to pathogens remains largely unknown in plants, especially trees. To investigate whether DNA methylation is involved in the response to infection process or is related to the resistance differences among poplars, we performed comprehensive whole-genome bisulfite sequencing of the infected stem of the susceptible type Populus × euramerican '74/76' and resistant type Populus tomentosa 'henan' upon Lonsdalea populi infection. The results revealed that DNA methylation changed dynamically in poplars during the infection process with a remarkable decrease seen in the DNA methylation ratio. Intriguingly, the resistant P. tomentosa 'henan' had a much lower basal DNA methylation ratio than the susceptible P. × euramerican '74/76'. Compared to mock-inoculation, both poplar types underwent post-inoculation CHH hypomethylation; however, significant decreases in mC and mCHH proportions were found in resistant poplar. In addition, most differentially CHH-hypomethylated regions were distributed in repeat and promoter regions. Based on comparison of DNA methylation modification with the expression profiles of genes, DNA methylation occurred in resistance genes, pathogenesis-related genes, and phytohormone genes in poplars during pathogen infection. Additionally, transcript levels of genes encoding methylation-related enzymes changed during pathogen infection. Interestingly, small-regulator miRNAs were subject to DNA methylation in poplars experiencing pathogen infection. This investigation highlights the critical role of DNA methylation in the poplar immune response to pathogen infection and provides new insights into epigenetic regulation in perennial plants in response to biotic stress.
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Pogostemon cablin is an important commercial source of patchouli oil, whose main active ingredient is patchouli alcohol. This sesquiterpene is a product of the mevalonate pathway, in which 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) is the rate-limiting enzyme. In this study, P. cablin HMGCR cDNA, comprising 2209 nucleotides encoding 425 amino acid residues was isolated, and bioinformatics analysis was used to analyze the protein sequence. Based on this analysis, a C-terminal truncated variant was engineered for recombinant expression in E. coli. The 38â¯kDa recombinant protein was identified by SDS-PAGE, and assayed for mevalonolactone production. According to the PcHMGCR1 gene sequence alignment with other species, the HMGCR protein had obvious resemblance with other plants HMG coenzyme A reductase and had homology with other species including plants, fungi, archaebacteria and animals. The prokaryotic expression vector was constructed by restriction enzyme digestion to be transformed into E. coli to express the recombinant protein, and 38â¯kDa recombinant protein was identified by the SDS-PAGE. Enzymatic activity was detected using GC-MS and, as a result, mevalonolactone was detected in the in vitro reaction mixture. Differential expression analysis showed that PcHMGCR1 expressed the highest amount in roots. The research results are of great significance for further research on the molecular biosynthesis mechanism of Patchouli alcohol in P. cablin.
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Hidroximetilglutaril-CoA Redutases/genética , Pogostemon/enzimologia , Animais , Clonagem Molecular , DNA Complementar , Escherichia coli , Hidroximetilglutaril-CoA Redutases/metabolismo , Ácido Mevalônico/análogos & derivados , Ácido Mevalônico/metabolismo , Pogostemon/genética , Sesquiterpenos/metabolismoRESUMO
Drought, cold, and high salinity are three major abiotic stresses effecting apple tree growth and fruit production. Understanding the genetic mechanisms of crosstalk between stress responses signalling networks and identifying the genes involved in apple has potential importance for crop improvement and breeding strategies. Here, the transcriptome profiling analysis of in vitro-grown apple plants subjected to drought, cold and high salinity stress, showed a total of 377 upregulated and 211 downregulated common differentially expressed genes (DEGs) to all 3 stress treatments compared with the control. Gene Ontology (GO) analysis indicated that these common DEGs were enriched in 'metabolic process' under the 'biological process' category, as well as in 'binding' and 'catalytic activity' under the 'molecular function' category. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that common DEGs were mainly belong to the 'biological functions' category and 17 DEGs were identified in 'environmental information processing' sub-category which may act as signal transduction components in response crosstalk regulation. Overexpression of 5 upregulated genes individually, out of these 17 common DEGs in apple calli promoted the consistent upregulation of DREB6, CBF1 and ZAT10 and increased the mass weight and antioxidase ability, implying these five common DEGs involved in multiple pathways and improved comprehensive resistance to stress.
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Temperatura Baixa , Secas , Perfilação da Expressão Gênica , Malus/fisiologia , Salinidade , Estresse FisiológicoRESUMO
Herein, binding of the ß-cyclodextrin (ß-CD) host to the unstable aryl pentazole guest has been confirmed experimentally and theoretically. After the confinement of aryl pentazole, electron density reorganization was studied by M06-2X dispersion-corrected DFT and further reflected in the characteristic shift in the NMR spectra. Among the host-guest complexes, the inclusion complex is favored with the phenyl ring expectedly encapsulated within the cavity through noncovalent interactions such as hydrogen bonding, C-Hπ, and the special Csp2-HH-Csp3 bonding discovered by the NBO, QTAIM, and NCI-RDG theories. The host-guest binding renders the enhancement of the nitrogen-ring aromatic character; this has been analyzed by employing nucleus-independent chemical shift (NICS)-based profiles. The non-covalent interaction largely enhances the thermal stability of the guest through a change of the decomposition reaction path whether the guest is encapsulated or not by the host. By comparison of the structures of B1-B4, the enhancement could be assigned to the ion-type transition structure stabilized by the C-H bonds of the host.
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BACKGROUND: Compared with traditional open surgery, minimally invasive surgery may improve recovery and patient satisfaction while maintaining surgical principles. Laparoscopic, single incision, natural orifice, and robotic approaches hold their own appeal. However, they lack the ability to manipulate organs as easily as the human hand. Advances in minimally invasive surgical techniques require new tools with increased functionality of the end effectors. Multifunctional tools with greater dexterity than those currently available are highly desired. METHODS: To address this need, we designed, fabricated, and tested the first prototype of a laparoscopic tool that provides the dexterity of a hand. The "hand" has two jointed fingers and a jointed thumb attached to a laparoscopic sheath that can be collapsed to fit through a 12-mm trocar or small orifice. The handle provides control for three independent degrees of freedom: finger motion (bending/spreading), fingertip bending, and thumb bending. The tool can be used for pinching, grasping, and spreading motions. Furthermore, the thumb is "double jointed" so that the tool can be converted to a rake configuration to allow lifting motions. The initial prototype has been tested in a cadaver lab to demonstrate its utility. RESULTS: Our "lap-hand" was used to complete standard surgical tasks in a simulation device in a time comparable to open and laparoscopic approaches, including "bowel" manipulation and peg movement. Cadaver testing confirmed the ability to grasp, elevate, and move liver, stomach, colon, and small bowel in a fashion expected by the hand. No adverse events were noted, and no bowel injury or perforation resulted from over-grasping. CONCLUSIONS: We have designed, built, and tested a first prototype of an artificial hand for minimally invasive surgery. Use of such tools could both reduce the number of hand-incisions required and potentially transition more patients to undergo their abdominal procedures laparoscopically.
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Laparoscopia/instrumentação , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Robótica/instrumentação , Cadáver , Mãos , Força da Mão , Humanos , Laparoscopia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Instrumentos CirúrgicosRESUMO
A family of energetic salts with high thermal stability and low impact sensitivity based on an oxygen-containing cation, 2,4-diamino-1,3,5-triazine-6-one, were synthesized and fully characterized by IR and multinuclear ((1)H, (13)C) NMR spectroscopy, elemental analysis, and differential scanning calorimetry. Insights into their sensitivities towards impact, friction, and electrostatics were gained by submitting the materials to standard tests. The structures of 2,4-diamino-1,3,5-triazine-6-one nitrate, 2,4-diamino-1,3,5-triazine-6-one sulfate, 2,4-diamino-1,3,5-triazine-6-one perchlorate, 2,4-diamino-1,3,5-triazine-6-one 5-nitrotetrazolate were determined by single-crystal X-ray diffraction; their densities are 1.691, 1.776, 1.854, and 1.636â g cm(-3), respectively. Most of the salts decompose at temperatures over 180 °C; in particular, the salts 2,4-diamino-1,3,5-triazine-6-one nitrate and 2,4-diamino-1,3,5-triazine-6-one perchlorate, which decompose at 303.3 and 336.4 °C, respectively, are fairly stable. Furthermore, most of the salts exhibit excellent impact sensitivities (>40â J), friction sensitivities (>360â N), and are insensitive to electrostatics. The measured densities of these energetic salts range from 1.64 to 2.01â g cm(-3) . The detonation pressure values calculated for these salts range from 14.6 to 29.2â GPa, and the detonation velocities range from 6536 to 8275â m s(-1) ; these values make the salts potential candidates for thermally stable and insensitive energetic materials.
RESUMO
The major elements in the early neolithic potteries unearthed from Xiaohuangshan site, Zhejiang Province and Jiahu site, Henan Province were determined by energy disperse X-ray fluorescence (EDXRF). The results show that the chemical compositions of the potteries from these two sites possess obvious regional features respectively. Compared with the specimen from Jiahu site, the potteries from Xiaohuangshan site have the common feature of ancient Chinese southern ceramics with high silicon and low aluminum contents. Simultaneously, the chemical composition of Xiaohuangshan pottery samples nearly unchanged from its early stage to the last stage. This phenomenon indicates that the source of the ceramic raw materials of Xiaohuangshan site was stable, and the continuous improvement of its pottery quality was mainly due to the progress in sintering techniques. However, the chemical composition of Jiahu potteries changed a lot in its three different periods. This change occurred because a large number of admixtures were added to the pottery bodies to improve their operating performances. These results also show that the improvements of pottery making techniques in different Chinese areas may have their own evolution directions respectively for the different geographical environments.