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1.
Plant Cell ; 34(10): 3983-4006, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-35897144

RESUMO

Miniature inverted-repeat transposable elements (MITEs) are widely distributed in the plant genome and can be methylated. However, whether DNA methylation of MITEs is associated with induced allelic expression and drought tolerance is unclear. Here, we identified the drought-inducible MdRFNR1 (root-type ferredoxin-NADP+ oxidoreductase) gene in apple (Malus domestica). MdRFNR1 plays a positive role in drought tolerance by regulating the redox system, including increasing NADP+ accumulation and catalase and peroxidase activities and decreasing NADPH levels. Sequence analysis identified a MITE insertion (MITE-MdRF1) in the promoter of MdRFNR1-1 but not the MdRFNR1-2 allele. MdRFNR1-1 but not MdRFNR1-2 expression was significantly induced by drought stress, which was positively associated with the MITE-MdRF1 insertion and its DNA methylation. The methylated MITE-MdRF1 is recognized by the transcriptional anti-silencing factors MdSUVH1 and MdSUVH3, which recruit the DNAJ domain-containing proteins MdDNAJ1, MdDNAJ2, and MdDNAJ5, thereby activating MdRFNR1-1 expression under drought stress. Finally, we showed that MdSUVH1 and MdDNAJ1 are positive regulators of drought tolerance. These findings illustrate the molecular roles of methylated MITE-MdRF1 (which is recognized by the MdSUVH-MdDNAJ complex) in induced MdRFNR1-1 expression as well as the drought response of apple and shed light on the molecular mechanisms of natural variation in perennial trees.


Assuntos
Secas , Malus , Alelos , Catalase/genética , Elementos de DNA Transponíveis/genética , Ferredoxinas/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Malus/genética , Malus/metabolismo , Metilação , NADP/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
Br J Haematol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955502

RESUMO

This open-label, prospective trial evaluated the combination of ixazomib, cyclophosphamide and dexamethasone (ICD) in 12 newly diagnosed POEMS syndrome patients. The study is registered with the Chinese Clinical Trials Registry (ChiCTR2000030072). The treatment protocol consisted of 12 cycles of the ICD regimen compromising ixazomib (4 mg on Days 1, 8 and 15), oral cyclophosphamide (300 mg on Days 1, 8 and 15) and dexamethasone (20 mg weekly). A total of 12 patients received a median of 10 (range: 3-23) cycles of the ICD regimen. The haematological response could be evaluated in 10 patients. The overall haematological response rate was 80% (8/10), with 30% (3/10) achieving complete haematological response, and the overall serum VEGF response rate and neurological response were 100% and 83.3% respectively. Two patients experienced grade 3/4 AEs, including diarrhoea (n = 1) and leukopenia (n = 1). The combination of ixazomib, cyclophosphamide and dexamethasone demonstrated both efficacy and safety in newly diagnosed POEMS syndrome, making it a viable treatment option.

3.
New Phytol ; 243(3): 1050-1064, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38872462

RESUMO

Branch number is one of the most important agronomic traits of fruit trees such as peach. Little is known about how LncRNA and/or miRNA modules regulate branching through transcription factors. Here, we used molecular and genetic tools to clarify the molecular mechanisms underlying brassinosteroid (BR) altering plant branching. We found that the number of sylleptic branch and BR content in pillar peach ('Zhaoshouhong') was lower than those of standard type ('Okubo'), and exogenous BR application could significantly promote branching. PpTCP4 expressed great differentially comparing 'Zhaoshouhong' with 'Okubo'. PpTCP4 could directly bind to DWARF2 (PpD2) and inhibited its expression. PpD2 was the only one differentially expressed key gene in the path of BR biosynthesis. At the same time, PpTCP4 was identified as a target of miR6288b-3p. LncRNA1 could act as the endogenous target mimic of miR6288b-3p and repress expression of miR6288b-3p. Three deletions and five SNP sites of lncRNA1 promoter were found in 'Zhaoshouhong', which was an important cause of different mRNA level of PpTCP4 and BR content. Moreover, overexpressed PpTCP4 significantly inhibited branching. A novel mechanism in which the lncRNA1-miR6288b-3p-PpTCP4-PpD2 module regulates peach branching number was proposed.


Assuntos
Brassinosteroides , Regulação da Expressão Gênica de Plantas , MicroRNAs , Proteínas de Plantas , Prunus persica , RNA Longo não Codificante , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Prunus persica/genética , Prunus persica/crescimento & desenvolvimento , Prunus persica/metabolismo , Brassinosteroides/metabolismo , Brassinosteroides/biossíntese , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Sequência de Bases , Polimorfismo de Nucleotídeo Único/genética , Genes de Plantas
4.
Plant Physiol ; 193(4): 2513-2537, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37648253

RESUMO

Grafting can facilitate better scion performance and is widely used in plants. Numerous studies have studied the involvement of mRNAs, small RNAs, and epigenetic regulations in the grafting process. However, it remains unclear whether the mRNA N6-methyladenosine (m6A) modification participates in the apple (Malus x domestica Borkh.) grafting process. Here, we decoded the landscape of m6A modification profiles in 'Golden delicious' (a cultivar, Gd) and Malus prunifolia 'Fupingqiuzi' (a unique rootstock with resistance to environmental stresses, Mp), as well as their heterografted and self-grafted plants. Interestingly, global hypermethylation of m6A occurred in both heterografted scion and rootstock compared with their self-grafting controls. Gene Ontology (GO) term enrichment analysis showed that grafting-induced differentially m6A-modified genes were mainly involved in RNA processing, epigenetic regulation, stress response, and development. Differentially m6A-modified genes harboring expression alterations were mainly involved in various stress responses and fatty acid metabolism. Furthermore, grafting-induced mobile mRNAs with m6A and gene expression alterations mainly participated in ABA synthesis and transport (e.g. carotenoid cleavage dioxygenase 1 [CCD1] and ATP-binding cassette G22 [ABCG22]) and abiotic and biotic stress responses, which might contribute to the better performance of heterografted plants. Additionally, the DNA methylome analysis also demonstrated the DNA methylation alterations during grafting. Downregulated expression of m6A methyltransferase gene MdMTA (ortholog of METTL3) in apples induced the global m6A hypomethylation and distinctly activated the expression level of DNA demethylase gene MdROS1 (REPRESSOR OF SILENCING 1) showing the possible association between m6A and 5mC methylation in apples. Our results reveal the m6A modification profiles in the apple grafting process and enhance our understanding of the m6A regulatory mechanism in plant biological processes.


Assuntos
Metilação de DNA , Malus , Metilação de DNA/genética , Malus/genética , Epigênese Genética , Transplante Heterólogo , Adenosina/genética
5.
Langmuir ; 40(20): 10571-10579, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38725094

RESUMO

In this work, polydopamine (PDA) and polyetheramine D230 were selected to construct the PDA-D230 interphase between the carbon fiber (CF) and epoxy matrix. Density functional theory (DFT) and molecular dynamics (MD) simulations were performed to explore the interface enhancement mechanisms of a carbon fiber reinforced polymer (CFRP) with the PDA-D230 interphase from the molecular level. The adsorption characteristics of a PDA molecule on the CF surface were investigated using the DFT method. The results show that stronger π-π stacking interactions are formed due to the structure and orientation preference of the PDA molecule. The interfacial structures and properties of CFRP with the PDA-D230 interphase are derived from MD simulations. The PDA-D230 interphase on the CF surface induces stronger interfacial interaction energy, leading to the better load transfer between the CF and epoxy matrix. The existence of the PDA-D230 interphase on the CF surface can decrease the mean-square displacement (MSD) value and the free volume fraction of CFRP, which restricts the movement of epoxy atoms and inhibits the translational and rotational motion of epoxy chains. Compared with the epoxy using pristine CFs as reinforcement, the interfacial shear stress (ISS) of CFRP with the PDA-D230 interphase is improved by 13.1%. Our results provide valuable insights into the interface characteristics of CFRP with the PDA-D230 interphase, which are of great significance for exploring the strengthening mechanisms for CFRPs with the PDA-D230 interphase.

6.
Plant J ; 109(5): 1271-1289, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34918398

RESUMO

Drought significantly limits apple fruit production and quality. Decoding the key genes involved in drought stress tolerance is important for breeding varieties with improved drought resistance. Here, we identified GRETCHEN HAGEN3.6 (GH3.6), an indole-3-acetic acid (IAA) conjugating enzyme, to be a negative regulator of water-deficit stress tolerance in apple. Overexpressing MdGH3.6 reduced IAA content, adventitious root number, root length and water-deficit stress tolerance, whereas knocking down MdGH3.6 and its close paralogs increased IAA content, adventitious root number, root length and water-deficit stress tolerance. Moreover, MdGH3.6 negatively regulated the expression of wax biosynthetic genes under water-deficit stress and thus negatively regulated cuticular wax content. Additionally, MdGH3.6 negatively regulated reactive oxygen species scavengers, including antioxidant enzymes and metabolites involved in the phenylpropanoid and flavonoid pathway in response to water-deficit stress. Further study revealed that the homolog of transcription factor AtMYB94, rather than AtMYB96, could bind to the MdGH3.6 promoter and negatively regulated its expression under water-deficit stress conditions in apple. Overall, our results identify a candidate gene for the improvement of drought resistance in fruit trees.


Assuntos
Malus , Desidratação , Secas , Regulação da Expressão Gênica de Plantas/genética , Malus/metabolismo , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Água/metabolismo
7.
Plant Physiol ; 188(3): 1686-1708, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34893896

RESUMO

Drought stress tolerance is a complex trait regulated by multiple factors. Here, we demonstrate that the miRNA160-Auxin Response Factor 17 (ARF17)-HYPONASTIC LEAVES 1 module is crucial for apple (Malus domestica) drought tolerance. Using stable transgenic plants, we found that drought tolerance was improved by higher levels of Mdm-miR160 or MdHYL1 and by decreased levels of MdARF17, whereas reductions in MdHYL1 or increases in MdARF17 led to greater drought sensitivity. Further study revealed that modulation of drought tolerance was achieved through regulation of drought-responsive miRNA levels by MdARF17 and MdHYL1; MdARF17 interacted with MdHYL1 and bound to the promoter of MdHYL1. Genetic analysis further suggested that MdHYL1 is a direct downstream target of MdARF17. Importantly, MdARF17 and MdHYL1 regulated the abundance of Mdm-miR160. In addition, the Mdm-miR160-MdARF17-MdHYL1 module regulated adventitious root development. We also found that Mdm-miR160 can move from the scion to the rootstock in apple and tomato (Solanum lycopersicum), thereby improving root development and drought tolerance of the rootstock. Our study revealed the mechanisms by which the positive feedback loop of Mdm-miR160-MdARF17-MdHYL1 influences apple drought tolerance.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Secas , Ácidos Indolacéticos/metabolismo , Malus/genética , Malus/metabolismo , MicroRNAs/efeitos dos fármacos , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Desidratação/genética , Desidratação/fisiopatologia , Regulação da Expressão Gênica de Plantas , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas
8.
Artif Organs ; 47(1): 62-76, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36102372

RESUMO

BACKGROUND: Tympanic membrane perforation (TMP) is a common disease in otology, and few acellular techniques have been reported for repairing this condition. Decellularized extracellular matrix (ECM) scaffolds have been used in organ reconstruction. OBJECTIVE: This study on tissue engineering aimed to develop a tympanic membrane (TM) scaffold prepared using detergent immersion and bone marrow mesenchymal stem cells (BMSCs) as repair materials to reconstruct the TM. RESULTS: General structure was observed that the decellularized TM scaffold with BMSCs retained the original intact anatomical ECM structure, with no cell residue, as observed using scanning electron microscopy (SEM), and exhibited low immunogenicity. Therefore, we seeded the decellularized TM scaffold with BMSCs for recellularization. Histology and eosin staining, SEM and immunofluorescence in vivo showed that the recellularized TM patch had a natural ultrastructure and was suitable for the migration and proliferation of BMSCs. The auditory brainstem response (ABR) evaluated after recellularized TM patch repair was slightly higher than that of the normal TM, but the difference was not significant. CONCLUSION: The synthetic ECM scaffold provides temporary physical support for the three-dimensional growth of cells during the tissue developmental stage. The scaffold stimulates cells to secrete their own ECM required for tissue regeneration. The recellularized TM patch shows potential as a natural, ultrastructure biological material for TM reconstruction.


Assuntos
Células-Tronco Mesenquimais , Perfuração da Membrana Timpânica , Humanos , Alicerces Teciduais/química , Matriz Extracelular/química , Perfuração da Membrana Timpânica/terapia , Membrana Timpânica , Engenharia Tecidual/métodos , Células da Medula Óssea
9.
Int J Mol Sci ; 24(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36983039

RESUMO

Osteoporosis, a common systematic bone homeostasis disorder related disease, still urgently needs innovative treatment methods. Several natural small molecules were found to be effective therapeutics in osteoporosis. In the present study, quercetin was screened out from a library of natural small molecular compounds by a dual luciferase reporter system. Quercetin was found to upregulate Wnt/ß-catenin while inhibiting NF-κB signaling activities, and thereby rescuing osteoporosis-induced tumor necrosis factor alpha (TNFα) impaired BMSCs osteogenesis. Furthermore, a putative functional lncRNA, Malat1, was shown to be a key mediator in quercetin regulated signaling activities and TNFα-impaired BMSCs osteogenesis, as mentioned above. In an ovariectomy (OVX)-induced osteoporosis mouse model, quercetin administration could significantly rescue OVX-induced bone loss and structure deterioration. Serum levels of Malat1 were also obviously rescued in the OVX model after quercetin treatment. In conclusion, our study demonstrated that quercetin could rescue TNFα-impaired BMSCs osteogenesis in vitro and osteoporosis-induced bone loss in vivo, in a Malat1-dependent manner, suggesting that quercetin may serve as a therapeutic candidate for osteoporosis treatment.


Assuntos
Doenças Ósseas Metabólicas , Osteoporose , RNA Longo não Codificante , Camundongos , Animais , Feminino , Humanos , Osteogênese/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/uso terapêutico , Fator de Necrose Tumoral alfa/farmacologia , Quercetina/farmacologia , Quercetina/uso terapêutico , Medula Óssea/patologia , Osteoporose/etiologia , Osteoporose/genética , Ovariectomia/efeitos adversos , Células-Tronco/patologia , Diferenciação Celular , Via de Sinalização Wnt
10.
J Infect Dis ; 225(11): 1991-2001, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35235942

RESUMO

BACKGROUND: Antigens of migrating schistosomula are promising candidates as schistosomiasis vaccine targets, since immune attack on hepatic schistosomula would interrupt the parasites life cycle and reduce egg burden on the host. METHODS: In this study, we report a collection of Schistosoma japonicum schistosomula proteins (SjScPs) that are highly expressed in hepatic schistosomula. The expression characteristics, antigenicity and immune protection of these proteins were studied by western blot, ELISA, immunofluorescence and challenge assays. RESULTS: We found that several of these SjScPs were highly antigenic and could effectively stimulate humoral immune responses in both human and other mammalian hosts. In particular, SjScP25, SjScP37, SjScP41, SjScP80, and SjScP88 showed high potential as biomarkers for schistosomiasis immunodiagnosis. Furthermore, we demonstrated that immunization with several of the recombinant SjScPs were able to protect mice from S japonicum challenge infection, with SjScP25 generating the most protective results. CONCLUSIONS: Our work represents a group of novel schistosome immunogens, which may be promising schistosomiasis japonica diagnosis and vaccine candidates.


Assuntos
Schistosoma japonicum , Esquistossomose Japônica , Esquistossomose , Vacinas , Animais , Testes Imunológicos , Mamíferos , Camundongos , Esquistossomose Japônica/diagnóstico , Esquistossomose Japônica/prevenção & controle
11.
New Phytol ; 234(4): 1294-1314, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35246985

RESUMO

Although the N6 -methyladenosine (m6 A) modification is the most prevalent RNA modification in eukaryotes, the global m6 A modification landscape and its molecular regulatory mechanism in response to drought stress remain unclear. Transcriptome-wide m6 A methylome profiling revealed that m6 A is mainly enriched in the coding sequence and 3' untranslated region in response to drought stress in apple, by recognizing the plant-specific sequence motif UGUAH (H=A, U or C). We identified a catalytically active component of the m6 A methyltransferase complex, MdMTA. An in vitro methyl transfer assay, dot blot, LC-MS/MS and m6 A-sequencing (m6 A-seq) suggested that MdMTA is an m6 A writer and essential for m6 A mRNA modification. Further studies revealed that MdMTA is required for apple drought tolerance. m6 A-seq and RNA-seq analyses under drought conditions showed that MdMTA mediates m6 A modification and transcripts of mRNAs involved in oxidative stress and lignin deposition. Moreover, m6 A modification promotes mRNA stability and the translation efficiency of these genes in response to drought stress. Consistently, MdMTA enhances lignin deposition and scavenging of reactive oxygen species under drought conditions. Our results reveal the global involvement of m6 A modification in the drought response of perennial apple trees and illustrate its molecular mechanisms, thereby providing candidate genes for the breeding of stress-tolerant apple cultivars.


Assuntos
Secas , Malus , Cromatografia Líquida , Regulação da Expressão Gênica de Plantas , Lignina , Malus/genética , Estresse Oxidativo , Melhoramento Vegetal , Estabilidade de RNA , Estresse Fisiológico/genética , Espectrometria de Massas em Tandem , Transcriptoma/genética
12.
Plant Physiol ; 185(4): 1924-1942, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33793944

RESUMO

Less than 40% of the nitrogen (N) fertilizer applied to soil is absorbed by crops. Thus, improving the N use efficiency of crops is critical for agricultural development. However, the underlying regulation of these processes remains largely unknown, particularly in woody plants. By conducting yeast two-hybrid assays, we identified one interacting protein of MdMYB88 and MdMYB124 in apple (Malus × domestica), namely BTB and TAZ domain protein 2 (MdBT2). Ubiquitination and protein stabilization analysis revealed that MdBT2 ubiquitinates and degrades MdMYB88 and MdMYB124 via the 26S proteasome pathway. MdBT2 negatively regulates nitrogen usage as revealed by the reduced fresh weight, dry weight, N concentration, and N usage index of MdBT2 overexpression calli under low-N conditions. In contrast, MdMYB88 and MdMYB124 increase nitrate absorption, allocation, and remobilization by regulating expression of MdNRT2.4, MdNRT1.8, MdNRT1.7, and MdNRT1.5 under N limitation, thereby regulating N usage. The results obtained illustrate the mechanism of a regulatory module comprising MdBT2-MdMYB88/MdMYB124-MdNRTs, through which plants modulate N usage. These data contribute to a molecular approach to improve the N usage of fruit crops under limited N acquisition.


Assuntos
Malus/genética , Malus/metabolismo , Nitrogênio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ubiquitinação/genética , Ubiquitinação/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Plantas Geneticamente Modificadas , Técnicas do Sistema de Duplo-Híbrido
13.
Artif Organs ; 46(7): 1268-1280, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35191556

RESUMO

BACKGROUND: Hypopharynx reconstruction after hypopharyngectomy is still a great challenge. Perfusion decellularization is for extracellular matrix (ECM) scaffolding and had been used in organ reconstruction. Our study aimed to prepare an acellular, natural, three-dimensional biological hypopharynx with vascular pedicle scaffold as the substitute materials to reconstruct hypopharynx. RESULT: Scanning electron microscope and histology staining showed that the decellularized hypopharynx with vascular pedicle scaffold retained intact native anatomical ECM structure. Myoblasts were observed on the recellularized scaffolds with bone marrow mesenchymal stem cells induced by 5-azacytidine implanted in the rabbit greater omentum by immunohistochemical analysis. CONCLUSION: The decellularized hypopharynx with vascular pedicle scaffold prepared by detergent perfusion in our study has a potential to be an alternative material to pharynx reconstruction.


Assuntos
Células-Tronco Mesenquimais , Alicerces Teciduais , Animais , Matriz Extracelular/química , Hipofaringe/cirurgia , Perfusão , Coelhos , Engenharia Tecidual/métodos , Alicerces Teciduais/química
14.
J Environ Manage ; 320: 115878, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36056491

RESUMO

The non-essential element cadmium (Cd) is one of the most problematic priority soil pollutants due to multitude of pollution sources, mobility in the environment and high toxicity to all living organisms. This strongly limits also the number and occurrence of species - Cd hyperaccumulators to be used for soil phytoremediation. However, efficient Cd hyperaccumulator Solanum nigrum L. appeared to commonly occur worldwide as a representative of Solanum nigrum complex of a great taxonomic diversity. This led to the idea that the search among different ecotypes of Solanum nigrum L. may result in the identifying the most efficient Cd hyperaccumulator without applying to soil any additional measures such as chemical ligands. In this first pioneering comparative study, three randomly selected ecotypes of S. nigrum L. ssp. nigrum from Shenyang (SY) and Hanzhong (HZ) in China, and Kyoto (KY) in Japan were used in pot experiments at soil treatments from 0 to 50 mg Cd kg-1. The Cd accumulation capacity appeared to represent KY > HZ > SY range, KY ecotype accumulating up to 73%, and HZ ecotype up to 67% bigger total Cd load than SY ecotype. At Cd content in soil up to 10 mg kg-1, no significant effect on the all ecotype biomass, photosynthetic activities, contents of first line defense antioxidant enzymes (CAT, SOD, GPX), and scavenging antioxidants ASA, GSH, was observed. At Cd in soil>10 mg kg-1all these parameters showed decreasing, and cell damage indicator MDA increasing trend, however total accumulated Cd load further increased up to 30 mg kg Cd in soil in all ecotypes in the same KY > HZ > SY sequence. The study proved the great potential of enhancing Cd accumulation capacity of S. nigrum species by selecting the most efficient ecotypes among commonly occurring representatives of S. nigrum complex worldwide. Moreover, these first comparative experiments convinced that the cosmopolitan character and great variety of species/subspecies belonging to Solanum nigrum complex all over the world opens the new area for successful soil phytoremediation with the use of the most appropriate eco/genotypes of S. nigtum as a tool for the best Cd-contaminated soil management practice.


Assuntos
Poluentes do Solo , Solanum nigrum , Antioxidantes/análise , Antioxidantes/farmacologia , Biodegradação Ambiental , Cádmio/química , Ecótipo , Raízes de Plantas/química , Solo/química , Poluentes do Solo/análise
15.
J Exp Bot ; 72(2): 592-607, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-32995885

RESUMO

The phytohormone abscisic acid (ABA) is involved in various plant processes. In response to drought stress, plants quickly accumulate ABA, but the regulatory mechanism of ABA accumulation is largely unknown, especially in woody plants. In this study, we report that MdMYB88 and MdMYB124 are myeloblastosis (MYB) transcription factors critical for ABA accumulation in apple trees (Malus x domestica) following drought, and this regulation is negatively controlled by ABA. MdMYB88 and MdMYB124 positively regulate leaf water transpiration, photosynthetic capacity, and stress endurance in apple trees under drought conditions. MdMYB88 and MdMYB124 regulate the expression of biosynthetic and catabolic genes of ABA, as well as drought- and ABA- responsive genes. MdMYB88 associates with promoter regions of the ABA biosynthetic gene 9-cis-epoxycarotenoid dioxygenase 3 (NCED3). Finally, expression of MdMYB88 and MdMYB124 is repressed by ABA. Our results identify a feedback regulation of MdMYB88 and MdMYB124 in modulating ABA homeostasis in apple trees.


Assuntos
Ácido Abscísico , Proteínas de Plantas , Secas , Retroalimentação , Regulação da Expressão Gênica de Plantas , Homeostase , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico
16.
Nanomedicine ; 27: 102192, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32229215

RESUMO

Due to the lack of effective strategies on the treatment of castration resistant prostate cancer (CRPC), we established a multifunctional nanoplatform (GNS@IR820/DTX-CD133) for the synergistic photothermal therapy (PTT)/photodynamic therapy (PDT)/chemotherapy (CT) under the monitoring of multimodal near-infrared (NIR) fluorescence/photoacoustic (PA) imaging. Benefiting from the guided effect of CD133 antibody, GNS@IR820/DTX-CD133 can targetedly deliver the loaded drug to the tumor tissues, which can further contribute to the combined therapeutic effect. Our experimental results prove that the bio-distribution of GNS@IR820/DTX-CD133 can be monitored with NIR fluorescence and PA imaging. In addition, the application of GNS@IR820/DTX-CD133 for in vitro and in vivo therapy achieves the excellent antitumor effects of the synergistic PTT/PDT/CT strategies under the NIR-light irradiation. Therefore, as a multifunctional nanoplatform integrating the PTT/PDT/CT strategies with tumor multimodal imaging or drug tracing, GNS@IR820/DTX-CD133 has the great potential for clinical applications in the antitumor therapy of CRPC.


Assuntos
Antígeno AC133/genética , Nanopartículas/química , Fotoquimioterapia , Terapia Fototérmica , Neoplasias de Próstata Resistentes à Castração/terapia , Antígeno AC133/química , Antígeno AC133/farmacologia , Animais , Linhagem Celular Tumoral , Terapia Combinada , Modelos Animais de Doenças , Docetaxel/química , Docetaxel/farmacologia , Sistemas de Liberação de Medicamentos , Ouro/química , Ouro/farmacologia , Xenoenxertos , Humanos , Verde de Indocianina/análogos & derivados , Verde de Indocianina/química , Verde de Indocianina/farmacologia , Masculino , Camundongos , Terapia de Alvo Molecular , Imagem Multimodal , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia
17.
J Exp Bot ; 70(12): 3139-3151, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-30970146

RESUMO

Auxin-dependent cell expansion is crucial for initiation of fiber cells in cotton (Gossypium hirsutum), which ultimately determines fiber yield and quality. However, the regulation of this process is far from being well understood. In this study, we demonstrate an antagonistic effect between cytokinin (CK) and auxin on cotton fiber initiation. In vitro and in planta experiments indicate that enhanced CK levels can reduce auxin accumulation in the ovule integument, which may account for the defects in the fiberless mutant xu142fl. In turn, supplementation with auxin can recover fiber growth of CK-treated ovules and mutant ovules. We further found that GhPIN3a is a key auxin transporter for fiber-cell initiation and is polarly localized to the plasma membranes of non-fiber cells, but not to those of fiber cells. This polar localization allows auxin to be transported within the ovule integument while specifically accumulating in fiber cells. We show that CKs antagonize the promotive effect of auxin on fiber cell initiation by undermining asymmetric accumulation of auxin in the ovule epidermis through down-regulation of GhPIN3a and disturbance of the polar localization of the protein.


Assuntos
Citocininas/metabolismo , Gossypium/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Óvulo Vegetal/metabolismo , Proteínas de Plantas/genética , Fibra de Algodão , Gossypium/genética , Gossypium/metabolismo , Epiderme Vegetal/metabolismo , Proteínas de Plantas/metabolismo
18.
Soft Matter ; 15(30): 6097-6106, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31271185

RESUMO

Self-assembled hydrogel materials constructed from cyclodextrin polymer (P-CD)/adamantane-modified poly acrylic acid (PAA-Ad) were designed and prepared via host-guest interactions. It was observed that the prepared supramolecular hydrogels had an interconnected three-dimensional porous network. In addition, the obtained hydrogels showed a recovery performance and it was confirmed that the host-guest interactions between ß-cyclodextrin and adamantane were the main driving force for the formation of the hydrogels. The mechanical properties of the hydrogels could be adjusted by varying the concentrations of PAA-Ad. In particular, the prepared supramolecular hydrogels exhibited superior performances in water purification. The results demonstrated that the hydrogels possessed different mechanisms in the adsorption of the four typical poisonous organic dye molecules used, including bisphenol A (BPA), 4-aminoazobenzene (N-Azo), methylene blue (MB), and rhodamine B (RhB). The hydrogels mainly adsorbed N-Azo by host-guest interaction and adsorbed BPA by host-guest interaction and hydrogen bond synergy. They also adsorbed MB and RhB by hydrogen bonding and electrostatic interaction.

20.
J Infect Dis ; 214(10): 1547-1556, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27638944

RESUMO

Cell-mediated immune responses play important roles in immune protection against Plasmodium infection. However, impaired immunity, such as lymphocyte exhaustion, is a common phenomenon in malaria. T-cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) is an important regulatory molecule in cell-mediated immunity and has been implicated in malaria. In this study, it was found that Tim-3 expression on key populations of lymphocytes was significantly increased in both Plasmodium falciparum-infected patients and Plasmodium berghei ANKA (PbANKA)-infected C57BL/6 mice. Upregulation of Tim-3 led to lymphocyte exhaustion, while blocking Tim-3 signaling with an anti-Tim-3 antibody restored lymphocyte activity in Plasmodium infections. Further, anti-Tim-3 treatment accelerated the parasite clearance and relieved the symptoms of cerebral malaria in PbANKA-infected mice. In conclusion, Tim-3 on immune cells negatively regulates cell-mediated immunity against Plasmodium infection, and blocking Tim-3 signaling enhances sterile immunity and may play a protective role during malarial parasite infections.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Imunidade Celular , Malária/imunologia , Plasmodium falciparum/imunologia , Animais , Voluntários Saudáveis , Receptor Celular 2 do Vírus da Hepatite A/antagonistas & inibidores , Humanos , Masculino , Camundongos Endogâmicos C57BL , Plasmodium berghei/imunologia
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