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1.
BMC Plant Biol ; 22(1): 11, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34979944

RESUMO

BACKGROUND: Compared with other abiotic stresses, drought stress causes serious crop yield reductions. Poly-γ-glutamic acid (γ-PGA), as an environmentally friendly biomacromolecule, plays an important role in plant growth and regulation. RESULTS: In this project, the effect of exogenous application of γ-PGA on drought tolerance of maize (Zea mays. L) and its mechanism were studied. Drought dramatically inhibited the growth and development of maize, but the exogenous application of γ-PGA significantly increased the dry weight of maize, the contents of ABA, soluble sugar, proline, and chlorophyll, and the photosynthetic rate under severe drought stress. RNA-seq data showed that γ-PGA may enhance drought resistance in maize by affecting the expression of ABA biosynthesis, signal transduction, and photosynthesis-related genes and other stress-responsive genes, which was also confirmed by RT-PCR and promoter motif analysis. In addition, diversity and structure analysis of the rhizosphere soil bacterial community demonstrated that γ-PGA enriched plant growth promoting bacteria such as Actinobacteria, Chloroflexi, Firmicutes, Alphaproteobacteria and Deltaproteobacteria. Moreover, γ-PGA significantly improved root development, urease activity and the ABA contents of maize rhizospheric soil under drought stress. This study emphasized the possibility of using γ-PGA to improve crop drought resistance and the soil environment under drought conditions and revealed its preliminary mechanism. CONCLUSIONS: Exogenous application of poly-γ-glutamic acid could significantly enhance the drought resistance of maize by improving photosynthesis, and root development and affecting the rhizosphere microbial community.


Assuntos
Secas , Fotossíntese/efeitos dos fármacos , Ácido Poliglutâmico/análogos & derivados , Rizosfera , Microbiologia do Solo , Zea mays/fisiologia , Microbiota/efeitos dos fármacos , Ácido Poliglutâmico/farmacologia , Zea mays/efeitos dos fármacos
2.
Ecotoxicol Environ Saf ; 227: 112880, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34655883

RESUMO

Phosphorus (P) containing minerals are identified as effective Pb stabilizers in soil, while their low solubility limit the Pb immobilization efficiency. In this work, the combination of phosphate solubilizing fungi (PSF) Penicillium oxalicum and tricalcium phosphate (TCP) was constructed and applied to improve Pb immobilization stabilities in medium and soils. P. oxalicum+ TCP could significantly improve Pb2+ removal to above 99% under different TCP/Pb2+ and pH values. TCP and P. oxalicum could remarkably immobilize Pb by ion exchange, and PbC2O4 precipitation or surface adsorption, respectively. While the enhanced Pb immobilization in P. oxalicum+ TCP was explained by stronger Pb2+ interaction with tryptophan protein-like substances in extracellular polymeric substance, and the formation of the most stable Pb-phosphate compound hydroxypyromorphite (Pb5(PO4)3OH). Toxicity characteristic leaching procedure test showed that only 0.91% of Pb2+ was leachable in P. oxalicum+ TCP treatment, significantly lower than that in P. oxalicum (2.90%) and TCP (7.52%) treatments. In addition, the lowest soil exchangeable Pb fraction (37.1%) and the highest available soil P (88.0 mg/kg) were both found in P. oxalicum+ TCP treatment. By synergistically forming stable Pb-containing products, thus the combination of PSF and P minerals could significantly improve Pb2+ immobilization and stability in soils.


Assuntos
Penicillium , Poluentes do Solo , Fosfatos de Cálcio , Matriz Extracelular de Substâncias Poliméricas/química , Chumbo , Fosfatos/análise , Solo , Poluentes do Solo/análise
3.
J Environ Manage ; 300: 113679, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34509816

RESUMO

Extensive mineral exploitation activities in history have aggravated potential toxic elements (PTEs) contamination in agricultural soils in China. Comprehensive ecological risk assessment is of great significance to orientate the restoration of contaminated soils, especially for those with high background values and multiple sources. The study area is located in the major rice producing area of China. Historically, there was a silver mine and a lead-zinc mine in the area, which were successively closed during the investigation. The intensive mining activities caused serious PTEs pollution in the agricultural soils around the mining area. In this study, five PTEs (As, Cd, Cr, Hg and Pb) selected to assessed the potential of geoaccumulation index in assessing agricultural soil potential risk assessment by identifying ecological risk sources. 315 of soil samples collected in 2009, 2014, 2018 were comprehensively analyzed by single pollution index evaluation (single factor index, geoaccumulation index), comprehensive evaluation (Nemerow index, potential ecological risk index) and trend analysis. Single factor index analysis showed that geoaccumulation index considered the impact of natural diagenesis of background values and human activities on the environment, ensuring high evaluation accuracy comparing to other methods used in typical complex agricultural soils. The modified potential ecological risk index revealed that the high background area did not represent high risk area, which was consistent with the implementation effect of governance measures. This study can provide important insights for policymakers and environmental engineers to quantitatively recognize the soil pollution and the effectiveness of governance based on applicable and reasonable evaluation methods.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Mineração , Medição de Risco , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
4.
J Agric Food Chem ; 69(37): 10838-10847, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34515475

RESUMO

The traditional pretreatment leads to the recalcitration of C-C bonds during lignin fractionation, thus hindering their depolymerization into aromatic monomers. It is essential to develop an applicable approach to extract noncondensed lignin for its high-value applications. In this work, noncondensed lignins were extracted from poplar sawdust using recyclable p-toluenesulfonic acid for cleaving lignin-carbohydrate complex bonds effectively and ethanol as a stabilization reagent to inhibit lignin condensation. Lignin yield of 83.74% was recovered by 3 mol/L acid in ethanol at 85 °C for 5 h, and carbohydrates were well preserved (retaining 98.97% cellulose and 50.01% hemicelluloses). During lignin fractionation, the acid concentration and extraction time were the major drivers of condensation. Ethanol reacted with lignin at the α-position to prevent the formation of the condensed structure. The extracted lignin depolymerized over the Pd/C catalysts gave a yield of 50.35% of aromatic monomers, suggesting that the novel extraction process provided a promising way for noncondensed lignin production.


Assuntos
Lignina , Populus , Benzenossulfonatos , Etanol , Madeira
5.
Hortic Res ; 8(1): 158, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34193839

RESUMO

Plant glandular trichomes (GTs) are epidermal outgrowths with the capacity to biosynthesize and secrete specialized metabolites, that are of great scientific and practical significance. Our understanding of the developmental process of GTs is limited, and no single plant species serves as a unique model. Here, we review the genetic mechanisms of GT initiation and development and provide a summary of the biosynthetic pathways of GT-specialized metabolites in nonmodel plant species, especially horticultural crops. We discuss the morphology and classification of GT types. Moreover, we highlight technological advancements in methods employed for investigating GTs. Understanding the molecular basis of GT development and specialized metabolites not only offers useful avenues for research in plant breeding that will lead to the improved production of desirable metabolites, but also provides insights for plant epidermal development research.

6.
J Orthop Translat ; 29: 78-88, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34136347

RESUMO

Background: Tunnel position deicide the isometry of graft attachment in synthetic anterior cruciate ligament (ACL) reconstruction. Near-isometric tunnel position may have advantage in graft integration and knee function in ACL reconstruction (ACLR) with polyethylene terephthalate (PET) ligament. Few studies focused on tunnel position isometry when conduct ACLR with an animal model. This study aimed to establish a preclinical rabbit model of near and non isometric ACLR with PET ligament and investigate the advantage of near-isometric ACLR compared to non-isometric ACLR. Methods: Nine hind limbs of rabbit were used in tunnel position study. Two femoral(anatomic, nonanatomic) tunnels and three tibial(anterior, middle, posterior) tunnels were used to measure tunnel position isometry during knee full range of motion. The tunnel position combination with minimal isometry was considered as near-isometric tunnel position. Then, 48 rabbits divided into two groups were conducted near or non isometric ACLR with PET ligament with graft fixation angle of 30° and constant tension of 5N. PET ligament isometry, range of motion(ROM) restriction, knee laxity were recorded after operation and followed up with macroscopic observation, microcomputed tomography (micro-CT) analysis, histology assessment and biomechanical test at 4 and 8 weeks postoperatively. Results: The tunnel combination with minimal isometry was femoral anatomic position and tibial posterior position(5.19 â€‹± â€‹1.78%) and considered as near-isometric tunnel position. ROM restriction were observed in non-isometric group (22.50 â€‹± â€‹14.14°) while none in near-isometric group. However, no ROM restriction observed at 8 weeks in both group. Knee laxity compared to contralateral knee were better in near-isometric group than non-isometric group (stable/slack/total 10/2/12 VS 3/9/12, p â€‹= â€‹0.012) at 8 weeks postoperatively. Supeiror PET ligament integration were also observed in near-isometric group through macroscopic observation, micro-CT analysis, histology assessment at both 4 and 8 weeks. The failure load in the Near-Isometric group at 8 weeks were higher than timezero reconstruction with statistical difference (156.8N â€‹± â€‹25.98N vs.102.6 â€‹± â€‹22.96N, p â€‹= â€‹0.02). Conclusion: A rabbit model of ACLR based on tunnel position isometry was successfully established in this study. The near-isometric tunnel position in rabbit model was femoral anatomic position and tibial posterior position. A near-isometric ACLR with PET ligament did not cause ROM restriction and had a better graft integration and follow-up stability than non-isometric ACLR with ROM restriction. The Translational Potential of this Article: The study demonstrate the establishmentof near-isometric tunnel position and non-isometric tunnel position with significant difference of ROM restriction and graft-bone integration. The described tunnel positions with differential isometry in a rabbit ACLR provides a reproducible and translational small animal model and enables preclinical research between tunnel position isometry and its affection on variable grafts, graft integration and knee function.

7.
Biology (Basel) ; 10(2)2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671192

RESUMO

Phosphorus (P) is a vital element in biological molecules, and one of the main limiting elements for biomass production as plant-available P represents only a small fraction of total soil P. Increasing global food demand and modern agricultural consumption of P fertilizers could lead to excessive inputs of inorganic P in intensively managed croplands, consequently rising P losses and ongoing eutrophication of surface waters. Despite phosphate solubilizing microorganisms (PSMs) are widely accepted as eco-friendly P fertilizers for increasing agricultural productivity, a comprehensive and deeper understanding of the role of PSMs in P geochemical processes for managing P deficiency has received inadequate attention. In this review, we summarize the basic P forms and their geochemical and biological cycles in soil systems, how PSMs mediate soil P biogeochemical cycles, and the metabolic and enzymatic mechanisms behind these processes. We also highlight the important roles of PSMs in the biogeochemical P cycle and provide perspectives on several environmental issues to prioritize in future PSM applications.

8.
Plant J ; 106(3): 753-765, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33577109

RESUMO

The fruit trichomes of Cucurbitaceae are widely desired in many Asian countries and have been a key determinant of cucumber (Cucumis sativus L.) cultivar selection for commercial production and breeding. However, our understanding of the initiation and development of cucumber trichomes is still limited. Here, we found that the cucumber TINY BRANCHED HAIR (TBH) gene is preferentially expressed in multicellular trichomes. Overexpression of CsTBH in tbh mutants restored the trichome phenotype and increased the percentage of female flowers, whereas silencing of CsTBH in wild-type plants resulted in stunted trichomes with a lower rate of female flowers. Furthermore, we provide evidence that CsTBH can directly bind to the promoters of cucumber 1-Aminocyclopropane-1-Carboxylate Synthase (CsACS) genes and regulate their expression, which affects multicellular trichome development, ethylene accumulation, and sex expression. Two cucumber acs mutants with different trichome morphology and sex morphs compared with their near-isogenic line further support our findings. Collectively, our study provides new information on the molecular mechanism of CsTBH in regulating multicellular trichome development and sex expression through an ethylene pathway.


Assuntos
Cucumis sativus/metabolismo , Etilenos/metabolismo , Genes de Plantas/genética , Redes e Vias Metabólicas , Fatores de Transcrição/genética , Tricomas/crescimento & desenvolvimento , Cucumis sativus/crescimento & desenvolvimento , Genes de Plantas/fisiologia , Regiões Promotoras Genéticas , Fatores de Transcrição/fisiologia , Tricomas/metabolismo
9.
Biomaterials ; 271: 120714, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33610048

RESUMO

Rotator cuff repair is a common surgery in sports medicine. During the surgery, torn tendon was re-fixed onto the bony surface. The majority of patients gain good results. However, re-tear occurs in some patients. The reason under this phenomenon is that the normal tendon-bone enthesis cannot be reconstructed. In order to strengthen the tendon-bone healing and promote enthesis regeneration, numerous manners are tested, among which stem cell related therapies are preferred. Stem cells, due to the ability of multi-lineage differentiation, are widely used in regenerative medicine. However, safety and ethics concerns limit its clinical use. Recent studies found that it is the secretome of stem cells that is biologically effective. On ground of this, we, in the current study, collected the conditioned medium of human bone marrow-derived stem cells (hBMSC-CM) and tested whether this acellular method could promote tendon-bone healing in a rat model of rotator cuff repair. By using histological, radiological, and biomechanical methods, we found that hBMSC-CM promoted tendon-bone healing of the rat rotator cuff. Then, we noticed that hBMSC-CM exerted an impact on macrophage polarization both in vivo and in vitro by inhibiting M1 phenotype and promoting M2 phenotype. Further, we proved that the benefit of hBMSC-CM on tendon-bone healing was related to its regulation on macrophage. Finally, we proved that, hBMSC-CM influenced macrophage polarization, which was, at least partially, related to Smad2/3 signaling pathway. Based on the experiments above, we confirmed the benefit of hBMSC-CM on tendon-bone healing, which relied on its immune-regulative property. Considering the accessibility and safety of acellular hBMSC-CM, we believe it is a promising candidate clinically for tendon-bone healing.


Assuntos
Lesões do Manguito Rotador , Manguito Rotador , Animais , Medula Óssea , Meios de Cultivo Condicionados/farmacologia , Humanos , Ratos , Lesões do Manguito Rotador/terapia , Células-Tronco , Tendões , Cicatrização
10.
Plant Sci ; 300: 110636, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33180714

RESUMO

Cucumber fruit wart composed of tubercule and spine (trichome on fruit) is not only an important fruit quality trait in cucumber production, but also a well-studied model for plant cell-fate determination. The development of spine is closely related to the initiation and formation of tubercule. The spine differentiation regulator CsGL1 has been proved to be epistatic to the tubercule initiation factor CsTu, which is the only connection to be identified between spine and tubercule formations. Our previous studies found that the MIXTA-LIKE transcription factor CsMYB6 can suppress fruit spine initiation, which is independent of CsGL1. How the formation of spine and tubercule is regulated at the molecular level by CsMYB6 remains poorly understood. In this study, we characterized cucumber 35S:CsMYB6 transgenic plants, which displayed an obvious reduction in the number and size of fruit spines and tubecules. Molecular analyses showed that CsMYB6 directly interacted with the key spine formation factor CsTTG1 in regulating the formation of fruit spine, and CsTu in regulating the initiation of fruit tubercule, respectively. Based on these evidences, a novel regulatory network is proposed by which CsMYB6/CsTTG1 and CsMYB6/CsTu complexes play an important role in regulating epidermal development, including spine formation and tubercule initiation in cucumber.


Assuntos
Cucumis sativus/anatomia & histologia , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/genética , Frutas/anatomia & histologia , Frutas/crescimento & desenvolvimento , Frutas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Fatores de Transcrição/genética , Tricomas/anatomia & histologia , Tricomas/genética , Tricomas/crescimento & desenvolvimento
11.
BMC Plant Biol ; 20(1): 528, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33213376

RESUMO

BACKGROUND: The characteristics of elephant grass, especially its stem lignocellulose, are of great significance for its quality as feed or other industrial raw materials. However, the research on lignocellulose biosynthesis pathway and key genes is limited because the genome of elephant grass has not been deciphered. RESULTS: In this study, RNA sequencing (RNA-seq) combined with lignocellulose content analysis and cell wall morphology observation using elephant grass stems from different development stages as materials were applied to reveal the genes that regulate the synthesis of cellulose and lignin. A total of 3852 differentially expressed genes (DEGs) were identified in three periods of T1, T2, and T3 through RNA-seq analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of all DEGs showed that the two most abundant metabolic pathways were phenylpropane metabolism, starch and sucrose metabolism, which were closely related to cell wall development, hemicellulose, lignin and cellulose synthesis. Through weighted gene co-expression network analysis (WGCNA) of DEGs, a 'blue' module highly associated with cellulose synthesis and a 'turquoise' module highly correlated with lignin synthesis were exhibited. A total of 43 candidate genes were screened, of which 17 had function annotations in other species. Besides, by analyzing the content of lignocellulose in the stem tissues of elephant grass at different developmental stages and the expression levels of genes such as CesA, PAL, CAD, C4H, COMT, CCoAMT, F5H and CCR, it was found that the content of lignocellulose was related to the expression level of these structural genes. CONCLUSIONS: This study provides a basis for further understanding the molecular mechanisms of cellulose and lignin synthesis pathways of elephant grass, and offers a unique and extensive list of candidate genes for future specialized functional studies which may promote the development of high-quality elephant grass varieties with high cellulose and low lignin content.


Assuntos
Metabolismo dos Carboidratos/genética , Celulose/metabolismo , Genoma de Planta/genética , Lignina/metabolismo , Pennisetum/genética , Transcriptoma , Parede Celular/metabolismo , Perfilação da Expressão Gênica , Lignina/análise , Redes e Vias Metabólicas/genética , Especificidade de Órgãos , Pennisetum/metabolismo , Polissacarídeos/metabolismo , Propano/metabolismo , Análise de Sequência de RNA , Amido/metabolismo , Sacarose/metabolismo
12.
J Hazard Mater ; 398: 123146, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32768845

RESUMO

Poly-γ-glutamic acid (γ-PGA) could efficiently stabilize heavy metals in the environment. This study characterized the effects of two plant growth-promoting and γ-PGA-producing bacteria Bacillus subtilis W7 and Bacillus amyloliquefaciens W25 on Cd immobilization and γ-PGA production in soil filtrate and on the biomass and Cd uptake by lettuce in Cd-contaminated soil, the impact of these strains on the rhizosphere soil bacterial community was also evaluated. The strains reduced Cd concentration (16-75 %) in soil filtrate and strain W25 had a higher ability of producing γ-PGA and immobilizing Cd than strain W7. Compared with the control, the strains significantly increased the biomass (41-85 %) and reduced Cd uptake (19-41 %) by lettuce, reduced available Cd content (25-37 %) and increased the relative abundance of γ-PGA-producing bacteria (24-30 %) in Cd-contaminated soil, among which the effects of strain W25 were better than that of strain W7. Besides, these isolates also increased soil pH value, urease activity and the relative abundance of plant growth-promoting and metal-immobilizing bacteria such as Sphingomonas and Bacillus. In summary, the two strains reduced soil available Cd and lettuce Cd uptake by increasing the pH value, urease activity and the abundance of γ-PGA-producing bacteria, and regulating bacterial community structure in rhizosphere soil.


Assuntos
Microbiota , Poluentes do Solo , Bactérias , Cádmio/análise , Ácido Glutâmico , Alface , Ácido Poliglutâmico/análogos & derivados , Rizosfera , Solo , Poluentes do Solo/análise
13.
J Exp Bot ; 71(18): 5425-5437, 2020 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-32490515

RESUMO

Cucumber is dioecious by nature, having both male and female flowers, and is a model system for unisexual flower development. Knowledge related to male flowering is limited, but it is reported to be regulated by transcription factors and hormone signals. Here, we report functional characterization of the cucumber (Cucumis sativus) GL2-LIKE gene, which encodes a homeodomain leucine zipper (HD-ZIP) IV transcription factor that plays an important role in regulating male flower development. Spatial-temporal expression analyses revealed high-level expression of CsGL2-LIKE in the male flower buds and anthers. CsGL2-LIKE is closely related to AtGL2, which is known to play a key role in trichome development. However, ectopic expression of CsGL2-LIKE in Arabidopsis gl2-8 mutant was unable to rescue the gl2-8 phenotype. Interestingly, the silencing of CsGL2-LIKE delayed male flowering by inhibiting the expression of the florigen gene FT and reduced pollen vigor and seed viability. Protein-protein interaction assays showed that CsGL2-LIKE interacts with the jasmonate ZIM domain protein CsJAZ1 to form a HD-ZIP IV-CsJAZ1 complex. Collectively, our study indicates that CsGL2-LIKE regulates male flowering in cucumber, and reveals a novel function of a HD-ZIP IV transcription factor in regulating male flower development of cucumber.


Assuntos
Cucumis sativus , Cucumis sativus/genética , Cucumis sativus/metabolismo , Fertilidade , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Zíper de Leucina , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Bioresour Technol ; 296: 122348, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31734059

RESUMO

In this work, the hydrolysis residue produced from the acidic concentrated lithium bromide hydrolysis (ALBH) of wheat straw, corn stover and elephant grass were characterized as biochar. The ALBH biochar as the black power had high content of carbon (49.65-55 wt%), specific surface areas (4.53-7.79 m2/g), porous structures (micropores, mesopores and macropores) and abundant oxygen functional groups (hydroxy, carbonyl, ester and ketone groups). These properties made ALBH biochar as a potential adsorbent for environmental remediation, with relatively high removal efficiency for a variety of heavy metal ions, especially hexavalent chromium (Cr(VI)). Therefore, ALBH technology may be an efficient strategy for synthesis of bio-char along with fermentable sugars, which met the concern of sustainability and green chemistry.


Assuntos
Carvão Vegetal , Poluentes Químicos da Água , Adsorção , Brometos , Cromo , Compostos de Lítio
15.
Hortic Res ; 6: 127, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31754434

RESUMO

Cucumber selective breeding over recent decades has dramatically increased productivity and quality, but the genomic characterizations and changes associated with this breeding history remain unclear. Here, we analyzed the genome resequencing data of 56 artificially selected cucumber inbred lines that exhibit various phenotypes to detect trait-associated sequence variations that reflect breeding improvement. We found that the 56 cucumber lines could be assigned to group 1 and group 2, and the two groups formed a distinctive genetic structure due to the breeding history involving hybridization and selection. Differentially selected regions were identified between group 1 and group 2, with implications for genomic-selection breeding signatures. These regions included known quantitative trait loci or genes that were reported to be associated with agronomic traits. Our results advance knowledge of cucumber genomics, and the 56 selected inbred lines could be good germplasm resources for breeding.

16.
Int J Mol Sci ; 20(21)2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31731414

RESUMO

Chitinases, a subgroup of pathogenesis-related proteins, are responsible for catalyzing the hydrolysis of chitin. Accumulating reports indicate that chitinases play a key role in plant defense against chitin-containing pathogens and are therefore good targets for defense response studies. Here, we undertook an integrated bioinformatic and expression analysis of the cucumber chitinases gene family to identify its role in defense against Fusarium oxysporum f. sp. cucumerinum. A total of 28 putative chitinase genes were identified in the cucumber genome and classified into five classes based on their conserved catalytic and binding domains. The expansion of the chitinase gene family was due mainly to tandem duplication events. The expression pattern of chitinase genes was organ-specific and 14 genes were differentially expressed in response to F. oxysporum challenge of fusarium wilt-susceptible and resistant lines. Furthermore, a class I chitinase, CsChi23, was constitutively expressed at high levels in the resistant line and may play a crucial role in building a basal defense and activating a rapid immune response against F. oxysporum. Whole-genome re-sequencing of both lines provided clues for the diverse expression patterns observed. Collectively, these results provide useful genetic resource and offer insights into the role of chitinases in cucumber-F. oxysporum interaction.


Assuntos
Quitinases , Cucumis sativus , Fusarium/crescimento & desenvolvimento , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Doenças das Plantas , Proteínas de Plantas , Quitinases/biossíntese , Quitinases/genética , Cucumis sativus/enzimologia , Cucumis sativus/genética , Cucumis sativus/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética
17.
Ecotoxicol Environ Saf ; 184: 109655, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31525561

RESUMO

This study investigated the effects of Cupriavidus sp. strain Cd02-mediated increase on biosorption and bioprecipitation of Cd2+ during the 144-h cultivation time as well as evaluated effectivenesses of changing soil pH and bioavailability of cadmium after bioaugmentation of strain Cd02 into Cd-contaminated paddy soil for 15 days. Results showed that strain Cd02-induced pH increase of the culture medium (from 7.40 to 8.68) facilitated biosorption of Cd2+ on Cd02 cell surface (4.82 mg/mg) and extracellular bioprecipitation in form of cadmium carbonate (3.07 mg/mg). Also, the pH values of Cd-contaminated paddy soil increased by 1.41 units after strain Cd02 was applied for 15 days, which thereby promoted the decrease of exchangeable fraction of Cd2+ by 6.5% in the tested paddy soil. Meanwhile, strain Cd02 could prosperously live in paddy soils after bioaugmentation. These results suggest that strain Cd02 may be applicable for bioremediation of the heavy metal-contaminated soils by bioaugmentation.


Assuntos
Cádmio/análise , Carbonatos/análise , Cupriavidus/metabolismo , Poluentes do Solo/análise , Solo/química , Biodegradação Ambiental , Disponibilidade Biológica , Biomineralização , Cádmio/metabolismo , Carbonatos/metabolismo , Cupriavidus/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Oryza/crescimento & desenvolvimento , Poluentes do Solo/metabolismo
18.
J Mater Chem B ; 7(31): 4801-4810, 2019 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-31389951

RESUMO

Tendons can transmit mechanical force from muscles to bones for movement. However, the mechanical strength of tendons is compromised after surgery, thus causing a high rate of tendon retear. Hence, the design and preparation of biodegradable materials with excellent mechanical properties have become an urgent demand for sports medicine. In this study, biomimetic polycaprolactone (PCL)/gelatin (Gel)-aligned scaffolds were fabricated for the mechanical restoration of the injured tendon in a rabbit model. The diameter of nanofibers was about 427.82 ± 56.99 nm, which was approximate to that of the native collagen fibrils; the directional consistency of the nanofibers in PCL/Gel-aligned scaffolds reached 77.33 ± 3.22%, which were ultrastructurally biomimetic. Compared to the observations for the control group, the in vitro mechanical results showed that the PCL/Gel-aligned scaffolds (P/G-A) were anisotropic in terms of failure load, tensile strength, and Young's modulus. After verifying their good cytocompatibility, the scaffolds were implanted into the rabbit patellar tendon in situ. The biomechanical properties of the repaired tendon in P/G-A reached 343.97 ± 65.30 N in failure load, 85.99 ± 16.33 MPa in tensile strength, 590.84 ± 201.87 MPa in Young's modulus, and 171.29 ± 61.50 N mm-1 in stiffness in vivo at 8 weeks post operation. In a word, our results demonstrated that P/G-A could support the regenerated tissue of injured patellar tendons to restore the biomechanical strength in a rabbit model. This suggested that the PCL/Gel-aligned scaffolds can pave a promising way to improve the healing of injured tendons in the clinic in the future.


Assuntos
Gelatina/química , Ligamento Patelar/metabolismo , Poliésteres/química , Traumatismos dos Tendões/terapia , Tecidos Suporte/química , Cicatrização/efeitos dos fármacos , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Módulo de Elasticidade , Masculino , Camundongos , Ligamento Patelar/citologia , Coelhos , Resistência à Tração
19.
Am J Sports Med ; 47(10): 2327-2337, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31306585

RESUMO

BACKGROUND: Stem cell-conditioned medium (CM) has been increasingly used in regenerative medicine. However, its effect on graft-host integration after anterior cruciate ligament (ACL) reconstruction (ACLR) remains unclear. PURPOSE: To examine the effect of human bone marrow stem cell (hBMSC)-CM on graft-bone integration and graft midsubstance ligamentization in a rat model of ACLR. STUDY DESIGN: Controlled laboratory study. METHODS: CM was obtained from the supernatant of commercially available hBMSCs in serum-free Dulbecco's modified Eagle medium (DMEM). In a rat model of an ACL injury, isometric ACLR was performed. Three groups were established: CM injection group (CM; n = 40), control injection group (CI; n = 40) with serum-free DMEM injections, and no injection group (NI; n = 40). An intra-articular injection was performed weekly. Micro-computed tomography was conducted at 2, 4, and 8 weeks postoperatively. Histological and biomechanical analyses were conducted at 4 and 8 weeks postoperatively. The NIH3T3 fibroblast was utilized as a model in vitro to examine the effect of CM using the cell counting kit-8 (CCK-8) assay and immunofluorescence staining of Ki-67, α-smooth muscle actin (α-SMA), and collagen 1 (Col 1). RESULTS: At 4 and 8 weeks, the femoral and tibial bone tunnel areas as well as the interface between the graft and host bone were smaller, while the bone volume/total volume ratio was higher, in the CM group. Sharpey-like fibers formed at 8 weeks in the CM group. At 4 and 8 weeks, more Col 1 was noticed in the CM group than in the NI group (both P < .001) or CI group (both P < .001). Immunohistochemically, the α-SMA-positive area was up-regulated at the graft-bone interface at 4 weeks (P < .001) and declined at 8 weeks (P < .001) in the CM group compared with the other 2 groups. At the midsubstance, α-SMA expression decreased from 4 to 8 weeks in all groups and was significantly lower in the CM group than in the NI group (P < .01) or CI group (P < .05) at 8 weeks. The CCK-8 assay showed that CM increased NIH3T3 viability (P < .001) and the level of Ki-67 (P < .05), α-SMA (P < .001), and Col 1 (P < .001) in CM-educated NIH3T3 cells. CONCLUSION: hBMSC-CM accelerates graft-bone incorporation and midsubstance ligamentization and enhances the proliferation, differentiation, and collagen synthesis of fibroblasts. CLINICAL RELEVANCE: Graft-host integration is essential after ACLR. The current study identified a novel agent, that is, hBMSC-CM, as a candidate for promoting integration.


Assuntos
Reconstrução do Ligamento Cruzado Anterior , Meios de Cultivo Condicionados , Cuidados Pós-Operatórios/métodos , Células-Tronco , Animais , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia , Osso e Ossos/patologia , Osso e Ossos/cirurgia , Fêmur/cirurgia , Humanos , Masculino , Camundongos , Células NIH 3T3 , Ratos , Tíbia/cirurgia , Microtomografia por Raio-X
20.
Development ; 146(14)2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31320327

RESUMO

Cucumber (Cucumis sativus L.) is an important vegetable crop that carries on vegetative growth and reproductive growth simultaneously. Indeterminate growth is favourable for fresh market under protected environments, whereas determinate growth is preferred for pickling cucumber in the once-over mechanical harvest system. The genetic basis of determinacy is largely unknown in cucumber. In this study, map-based cloning of the de locus showed that the determinate growth habit is caused by a non-synonymous SNP in CsTFL1 CsTFL1 is expressed in the subapical regions of the shoot apical meristem, lateral meristem and young stems. Ectopic expression of CsTFL1 rescued the terminal flower phenotype in the Arabidopsis tfl1-11 mutant and delayed flowering in wild-type Arabidopsis Knockdown of CsTFL1 resulted in determinate growth and formation of terminal flowers in cucumber. Biochemical analyses indicated that CsTFL1 interacts with a homolog of the miRNA biogenesis gene CsNOT2a; CsNOT2a interacts with FDP. Cucumber CsFT directly interacts with CsNOT2a and CsFD, and CsFD interacts with two 14-3-3 proteins. These data suggest that CsTFL1 competes with CsFT for interaction with CsNOT2a-CsFDP to inhibit determinate growth and terminal flower formation in cucumber.


Assuntos
Cucumis sativus , Flores/crescimento & desenvolvimento , Flores/genética , Fatores Genéricos de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Sequência Conservada , Cucumis sativus/genética , Cucumis sativus/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/fisiologia , Plantas Geneticamente Modificadas , Polimorfismo de Nucleotídeo Único , Ligação Proteica
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