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2.
J Nanobiotechnology ; 19(1): 240, 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34380522

RESUMO

BACKGROUND: There has been a great interest in developing strategies for enhancing antigen delivery to the mucosal immune system as well as identifying mucosal active immunostimulating agents. To elevate the potential of O-2'-Hydroxypropyl trimethyl ammonium chloride chitosan (O-2'-HACC) as an adjuvant and mucosal immune delivery carrier for DNA vaccine, we prepared the O-2'-HACC loaded with Newcastle disease virus (NDV) F gene plasmid DNA and C3d6 molecular adjuvant (O-2'-HACC/pFDNA microparticles). RESULTS: The O-2'-HACC/pFDNA exhibited a regular spherical morphology with a particle size of 202.3 ± 0.52 nm, a zeta potential of 50.8 ± 8.21 mV, encapsulation efficiency of 90.74 ± 1.10%, and a loading capacity of 49.84 ± 1.20%. The plasmid DNA could be sustainably released from the O-2'-HACC/pFDNA after an initial burst release. Intranasal vaccination of chickens immunized with O-2'-HACC/pFDNA not only induced higher anti-NDV IgG and sIgA antibody titers but also significantly promoted lymphocyte proliferation and produced higher levels of IL-2, IL-4, IFN-γ, CD4+, and CD8 + T lymphocytes compared with the NDV commercial live attenuated vaccine. Intranasal delivery of the O-2'-HACC/pFDNA enhanced humoral, cellular, and mucosal immune responses and protected chickens from the infection of highly virulent NDV compared with the intramuscular delivery. CONCLUSIONS: Collectively, our findings indicated that the O-2'-HACC could be used as a vaccine adjuvant and delivery system for mucosal immunity and have an immense application promise.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(4): 1050-1055, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34362481

RESUMO

OBJECTIVE: To investigate the effect of sulforaphane (SFN) on G2/M phase arrest of acute myeloid leukemia cells and its molecular mechanism. METHODS: KG1a and KG1cells were treated by different concentrations of SFN for 48 h. Flow cytometry (FCM) was used to analyze the phase distribution of cell cycle. High-throughput sequencing was used to detect the effect of SFN on the expression of cell cycle related genes in KG1a cells. The mRNA expression of P53, P21, CDC2 and CyclinB1 were detected by qPCR. The protein expression of P53, CDC2, P-CDC2 and CyclinB1 were detected by Western blot. RESULTS: Cells in the G2/M phase were increased from 11.9% to 54.0% in KG1a cells and 18.5% to 83.3% in KG1 cells after treated by SFN (8 µ mol / L) for 48 hours(P<0.001). KEGG analysis indicated that P53 pathway was enriched in KG1a cells after treated by SFN. The heat-map graph showed that SFN could change the relevant genes of the cell cycle in KG1a cells. After SFN treatment, the mRNA level of P53 and P21 were significantly increased in KG1 and KG1a cells(P<0.05 or P<0.01). The mRNA level of CDC2 showed a decrease trend with the increasing dose of SFN. At the dosage of 8 µmol /L, the mRNA expression levels of CDC2 was significantly lower than that in control group(P<0.05). At the same time, the protein level of P53 was significantly increased in KG1 and kG1a cells after treated by SFN(P<0.05). The protein level of CDC2 showed a decrease trend with the increasing dose of SFN in a dose manner(r=0.9482 and r=0.8977). The protein levels of CDC2 in SFN 8 and 12 µ mol/L groups were significantly lower than that in control group(P<0.05, P<0.01). The protein levels of P-CDC2 was increased. But the change of mRNA and protein level of CyclinB1 was not significant. CONCLUSION: SFN induces leukemia cells to block in G2/M phase by activating P53 signaling pathway, which can inhibit the expression of CDC2 and the activity of CDC2/cyclinB1.


Assuntos
Isotiocianatos , Leucemia Mieloide Aguda , Ciclo Celular , Humanos , Isotiocianatos/farmacologia , Mitose , Sulfóxidos
4.
AMB Express ; 11(1): 121, 2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34424425

RESUMO

Sulforaphane (SFN), an active compound in cruciferous vegetables, has been characterized by its antiproliferative capacity. We investigated the role and molecular mechanism through which SFN regulates proliferation and self-renewal of lung cancer stem cells. CD133+ cells were isolated with MACs from lung cancer A549 and H460 cells. In this study, we found that SFN inhibited the proliferation of lung cancer cells and self-renewal of lung cancer stem cells simultaneously. Meanwhile, the mRNA and protein expressions of Shh, Smo, Gli1 and PHC3 were highly activated in CD133+ lung cancer cells. Compared with siRNA-control group, Knock-down of Shh inhibited proliferation of CD133+ lung cancer cells, and decreased the protein expression of PHC3 in CD133+ lung cancer cells. Knock-down of PHC3 also affected the proliferation and decreased the Shh expression level in CD133+ lung cancer cells. In addition, SFN inhibited the activities of Shh, Smo, Gli1 and PHC3 in CD133+ lung cancer cells. Furthermore, the inhibitory effect of SFN on the proliferation of siRNA-Shh and siRNA-PHC3 cells was weaker than that on the proliferation of siRNA-control cells. Sonic Hedgehog signaling pathway might undergo a cross-talk with PHC3 in self-renewal of lung cancer stem cells. SFN might be an effective new drug which could inhibit self-renewal of lung cancer stem cells through the modulation of Sonic Hedgehog signaling pathways and PHC3. This study could provide a novel way to improve therapeutic efficacy for lung cancer stem cells.

5.
Infect Genet Evol ; 91: 104819, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33771724

RESUMO

Senecavirus A (SVA), an emerging swine pathogen, has been reported in many provinces of China since the first outbreak in 2015 in Guangdong province. In this study, 10 lymph nodes positive for SVA, collected between 2018 and 2019 from slaughterhouses in Guangdong province, were subjected to virus isolation. Rapid and evident cytopathic effects (CPEs) were observed in SVA-infected PK-15 cells, including shrinking, rounding and detaching, with peak titers being reached at 24 h post infection (hpi). Electron microscopy showed that SVA particles are spherical and approximately 30 nm in diameter, and exist as crystalline lattices in cytoplasm revealed by ultra-thin sectioning. Phylogenetic analysis based on the whole genome sequences of all available isolates showed that SVA globally can be divided into two groups with each being further divided into two subgroups (Ia-b and IIa-b), and with the Guangdong isolates obtained here and other Chinese strains belonging to subgroups IIa and IIb. Evolutionary analysis showed that the mean substitution rate of SVA was 2.696 × 10-3 per site per year based on whole genomic sequences, with subgroup IIb isolates having evolved faster than those of subgroup IIa. Analysis of efficient population size showed that the outbreak point of SVA worldwide occurred at the end of 2013 with that of subgroup IIb, the current dominant group, in mid 2014.

6.
Chem Commun (Camb) ; 57(17): 2128-2131, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33588430

RESUMO

In this study, we report a novel synthetic strategy to prepare a highly (110)-oriented ZIF-7 film possessing superior anti-corrosion properties via oriented epitaxial growth. Our work provides insights into facile preparation of oriented uniform MOF single seed layers and films with rod-shaped MOF seeds as building blocks.

7.
Environ Sci Pollut Res Int ; 28(15): 19260-19271, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33394406

RESUMO

Globally, urban has been the major contributor to greenhouse gas (GHG) emissions and thus plays an increasingly important role in its efforts to reduce CO2 emissions. However, quantifying city-level CO2 emissions is generally a difficult task due to lacking or lower quality of energy-related statistics data, especially for some underdeveloped areas. To address this issue, this study used a set of open access data and machine learning methods to estimate and predict city-level CO2 emissions across China. Two feature selection technologies including Recursive Feature Elimination and Boruta were used to extract the important critical variables and input parameters for modeling CO2 emissions. Finally, 18 out of 31 predictor variables were selected to establish prediction models of CO2 emissions. We found that the statistical indicators of urban environment pollution (such as industrial SO2 and dust emissions per capita) are the most important variables for predicting the city-level CO2 emissions in China. The XGBoost models obtained the highest estimation accuracy with R2 > 0.98 and lower relative error (about 0.8%) than other methods. The CO2 emissions predictive accuracy can be improved modestly by combing geospatial and meteorological interpolation predictor variables (e.g., DEM, annual average precipitation, and air temperature). We also observed an S-shape relationship between urban CO2 emissions per capita and urban economic growth when the rest variables were held constant, rather than a U-shaped one. The findings presented herein provide a first proof of concept that easily available socioeconomic statistical records and geospatial data at urban areas have the potential to accurately predict city-level CO2 emissions with the aid of machine learning algorithms. Our approach can be used to generate carbon footprint maps frequently for the undeveloped regions with scarce detailed energy-related statistical data, to assist policy-makers in designing specific measures of reducing and allocating carbon emissions reduction goal.


Assuntos
Acesso à Informação , Dióxido de Carbono , Dióxido de Carbono/análise , China , Cidades , Aprendizado de Máquina
8.
PLoS Pathog ; 17(1): e1008770, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33428670

RESUMO

Environments such as light condition influence the spread of infectious diseases by affecting insect vector behavior. However, whether and how light affects the host defense which further affects insect preference and performance, remains unclear, nor has been demonstrated how pathogens co-adapt light condition to facilitate vector transmission. We previously showed that begomoviral ßC1 inhibits MYC2-mediated jasmonate signaling to establish plant-dependent mutualism with its insect vector. Here we show red-light as an environmental catalyzer to promote mutualism of whitefly-begomovirus by stabilizing ßC1, which interacts with PHYTOCHROME-INTERACTING FACTORS (PIFs) transcription factors. PIFs positively control plant defenses against whitefly by directly binding to the promoter of terpene synthase genes and promoting their transcription. Moreover, PIFs interact with MYC2 to integrate light and jasmonate signaling and regulate the transcription of terpene synthase genes. However, begomovirus encoded ßC1 inhibits PIFs' and MYC2' transcriptional activity via disturbing their dimerization, thereby impairing plant defenses against whitefly-transmitted begomoviruses. Our results thus describe how a viral pathogen hijacks host external and internal signaling to enhance the mutualistic relationship with its insect vector.


Assuntos
Begomovirus/fisiologia , Hemípteros/virologia , Insetos Vetores/virologia , Doenças das Plantas/virologia , Simbiose , Proteínas Virais/metabolismo , Fatores de Virulência/metabolismo , Animais , Arabidopsis/metabolismo , Arabidopsis/virologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Luz , Fitocromo , Tabaco/metabolismo , Tabaco/virologia , Proteínas Virais/genética , Fatores de Virulência/genética
9.
Huan Jing Ke Xue ; 42(1): 501-512, 2021 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-33372504

RESUMO

Considering a background of global warming, the effect of urban heat island (UHI) has become a serious ecological and environmental problem that is commonly faced by modern cities worldwide, posing challenges to the physical and mental health of residents in urban areas, air quality, and the healthy growth of surface vegetation. Using time series MODIS land surface temperature data products from 2001 to 2018, we evaluated the urban heat island intensity (UHII) and its spatiotemporal patterns in 1232 major urban human settlement patches (area>10 km2) across China based on the consistency method. A random forest regression model (RF) was also used to reveal the driving mechanism of urban heat island intensity in China due to human activities, urban morphology, vegetation, topography, and meteorological factors. The results show that more than 90% of cities and towns in China have exhibited significant diurnal heat island phenomena on the scale of human settlements. The diurnal UHII reaches up to (0.75±0.6)℃ and (0.81±0.53)℃, respectively. The daytime UHII in summer was significantly higher than that in winter, while there was little difference in nighttime UHII between summer and winter. During the past 18 years, the daytime UHII in China has shown a slight downward trend, while the nighttime UHII has increased significantly, with no significant change in summer and on mean annual scales. In terms of spatial distribution, the eastern coastal provinces have higher daytime UHII than those of the western or plateau provinces, while the nighttime UHII shows the opposite pattern. The RF regression results show that the average annual rainfall and latitudinal position of cities and towns are the two most important factors controlling the daytime and nighttime UHII in China. Narrowing the differences in vegetation growth between urban and rural environments will have a mitigating effect on the daytime UHII, and controlling the expansion of small and medium-sized towns will also play a positive role in the continuously rising nighttime UHII.


Assuntos
Monitoramento Ambiental , Temperatura Alta , China , Cidades , Humanos , Ilhas
10.
Onco Targets Ther ; 13: 11177-11181, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33173309

RESUMO

Background: Osimertinib is a novel and irreversible epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) targeting EGFR sensitive mutations and EGFR exon20 p.T790M mutation, which demonstrated superior progression-free survival (PFS) and overall survival (OS). Case Presentation: We report a patient with lung adenocarcinoma harboring EGFR exon 19 deletion mutant treatment with icotinib. After 6 months, she developed EGFR exon20 p.T790M and then the patient received osimertinib treatment. A novel MYH9 (exon41)-RET (exon12) fusion and EGFR exon20 p.T790M loss were identified using plasma circulation tumor DNA (ctDNA) after osimertinib treatment, which led to rapid progression after osimertinib five months and suggested a potential resistance mechanism. Conclusion: Our findings expanded the spectrum of RET arrangement types and provided the basis for this hypothesis: acquired RET rearrangement and EGFR exon20 p.T790M loss potentially serve an additional resistance mechanism to osimertinib in EGFR-mutated non-small-cell lung cancer (NSCLC).

11.
Chem Asian J ; 15(22): 3812-3815, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-32997399

RESUMO

A straightforward method for the synthesis of spiro[cyclobuta[a]indene-7,1'-cyclobutane] derivatives from cyclobutanols has been developed via one-pot [3+2] spiroannulation. A series of new spiro[cyclobuta[a]indene-7,1'-cyclobutane] derivatives are facilely synthesized in good yields under mild reaction conditions.

12.
Immunol Lett ; 223: 26-32, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32333964

RESUMO

Porcine parvovirus (PPV) is one of the most common and important virus causes of infectious infertility in swine throughout the world. Inactivated PPV vaccine is broadly used, however, there is no appropriate immunomodulatory adjuvant for enhancing present vaccines and developing new ones. Therefore, in this study, the water-soluble N-2-Hydroxypropyl trimethyl ammonium chloride chitosan (N-2-HACC) was synthesized, the adjuvant potential of chitosan derivative was evaluated in inactivated PPV vaccine. Twenty adult healthy sows were assigned to four groups and vaccinated with synthesized PPV/N-2-HACC, commercial inactivated vaccine, N-2-HACC adjuvant and PBS. After insemination, all sows were challenged with the homologous PPV-H strain. In vivo immunization showed that sows immunized with the PPV/N-2-HACC induced more long-lasting HI antibodies and strong immune responses. Importantly, immunization of PPV/N-2-HACC significantly protected sows from homologous PPV-H strain infection. However, immunization of PPV/N-2-HACC didn't change the level of IL-2, IL-4 and IFN-γ and the production of CD4+, CD8 + T lymphocyte. The results indicated that PPV/N-2-HACC protect PPV infection mainly through enhancing the humoral immunity rather than cellular immunity. In addition, the mummified fetuses were observed from the control groups, but neither of the two vaccine groups. In conclusion, these results suggest that N-2-HACC can be exploited as an effective adjuvant for vaccine development, and the PPV/N-2-HACC are potent immunization candidates against PPV infection.


Assuntos
Quitosana/análogos & derivados , Retardo do Crescimento Fetal/imunologia , Infecções por Parvoviridae/imunologia , Parvovirus Suíno/fisiologia , Complicações Infecciosas na Gravidez/imunologia , Vacinas de Produtos Inativados/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais/sangue , Quitosana/imunologia , Feminino , Imunidade Humoral , Imunogenicidade da Vacina , Gravidez , Solubilidade , Suínos , Vacinação , Água
13.
ACS Appl Mater Interfaces ; 12(13): 15320-15327, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32160461

RESUMO

Layered molecular sieve membranes containing uniform interlayer galleries have offered unprecedented opportunities to reach a performance far beyond the Robeson upper bound line. In this study, we took the initiative to prepare layered zirconium phenylphosphonate (ZrPP) molecular sieve membranes with optimized microstructure on tetragonal zirconia (t-ZrO2) buffer layer-modified porous α-Al2O3 substrates by facile in situ hydrothermal growth. Relying on the 3.2 Å-sized gallery height and preferential CO2 adsorption behavior, prepared ZrPP membranes showed exceptional H2/CO2 selectivity (>100) as well as considerable H2 permeability. Furthermore, extraordinary thermal, mechanical, and chemical stability of ZrPP membranes made them potentially attractive for long-term operations under harsh conditions.

14.
J Burn Care Res ; 41(3): 657-662, 2020 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-32020201

RESUMO

In this study, we aimed to evaluate the therapeutic effects of autologous platelet-rich plasma (PRP) on deep partial-thickness burns in Bama pigs. Deep partial-thickness burn wounds were created on the back of Bama pigs. The reepithelialization time was compared between the PRP and control groups. The mean score of Ki67 (+) cells and α-SMA (+) vessels, the mean thickness of epidermis and dermis of the healing wounds were determined via H&E staining and immunohistochemical assay. The levels of the growth factors epidermal growth factor (EGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) were examined by ELISA. Our data showed that the time to wound reepithelialization was shorter in the PRP group compared with the control group. The thickness of the epidermis was larger in the PRP group compared with the control group. On the 7th and 14th days after the treatment, the mean score of Ki67 (+) cells and α-SMA (+) vessels were higher in the PRP group compared with the control group. The PRP group showed higher levels of growth factors (EGF, bFGF, and VEGF) compared with the control group by ELISA. The results indicated that PRP could improve wound healing process of deep partial-thickness burns in Bama pigs. The PRP increased the thickness of epidermis of the healed wounds, cell proliferation, and angiogenesis. We demonstrated that applying PRP had a greater potential for the treatment of deep partial-thickness burns.


Assuntos
Queimaduras/terapia , Plasma Rico em Plaquetas , Cicatrização/fisiologia , Animais , Biomarcadores/metabolismo , Proliferação de Células , Modelos Animais de Doenças , Neovascularização Fisiológica , Suínos
15.
ACS Appl Mater Interfaces ; 12(4): 4494-4500, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31873001

RESUMO

Preferred orientation has proven to exert a significant impact on the gas separation performance of metal-organic framework membranes. Nevertheless, realizing three-dimensional orientation control remains a challenging issue. In this study, well-intergrown NH2-UiO-66 membranes with both (111) out-of-plane and regional in-plane orientations were prepared by combining oriented deposition of seeds and solvothermal epitaxial growth. Dynamic air-liquid interface-assisted self-assembly method was employed to organize uniform octahedral-shaped NH2-UiO-66 seeds into closely packed monolayers with (111) out-of-plane and regional in-plane orientations, whereas the use of ZrS2 as the zirconium precursor during the solvothermal epitaxial growth was found indispensible for sealing the intercrystalline gaps while preserving the preferred orientation inherited from seed layers. In addition, compared with solvothermal heating, employing microwave heating led to poor intergrowth between neighboring NH2-UiO-66 crystals because of a lower dielectric loss factor of the reaction medium. Gas permeation results indicated that the prepared NH2-UiO-66 membranes exhibited H2/CO2 selectivity up to 5.5 times higher than their counterparts with random and/or mere out-of-plane orientations as well as H2 permeability 14.5 times higher than NH2-MIL-125(Ti) membranes with mere out-of-plane orientation under similar operating conditions.

16.
Front Vet Sci ; 6: 319, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616677

RESUMO

Porcine circovirus (PCV) is one of the smallest known DNA viruses in mammals. At present, PCVs are divided into three species, PCV1, PCV2, and PCV3. PCV1 and PCV2 were found in the 1970s and the 1990s, respectively, whereas PCV3 was discovered recently in 2016. PCV1 does not cause diseases in pigs. However, PCV3, similar to PCV2, is reported to be associated with several swine diseases, including porcine dermatitis and nephropathy syndrome (PDNS) and reproductive failure. PCVs are very common in domestic pigs as well as wild boars. However, PCVs have been occasionally isolated from non-porcine animals, including ruminants (such as cattle, goats, wild chamois, and roe deers), rodents (such as NMRI mice, BALB/c mice, Black C57 mice, ICR mice, Mus musculus, and Rattus rattus), canines (such as dogs, minks, foxes, and raccoon dogs), insects (such as flies, mosquitoes, and ticks), and shellfish. Moreover, PCVs are frequently reported in biological products, including human vaccines, animal vaccines, porcine-derived commercial pepsin products, and many cell lines. PCVs are also abundant in the environment, including water samples and air samples. Interestingly, PCV1 and/or PCV2 antibody or antigen has also been detected in sera, stool samples and respiratory swab samples of human, revealing zoonotic potential of PCVs. Thus, PCVs inhabit many types of reservoirs. In this review, we summarize the reservoirs of PCVs, and this information would be helpful in understanding the natural circulating status and possible cross-species transmission of PCVs.

17.
Int J Surg ; 71: 12-18, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31494331

RESUMO

INTRODUCTION: Previous results have indicated that CXCR4 is an oncogene in several types of human tumors including renal cell carcinoma (RCC). However, the correlation between CXCR4 expression and clinicopathological characteristics of RCC remains unclear. MATERIALS AND METHODS: We conducted a meta-analysis to quantitatively evaluate the association of CXCR4 expression with the incidence of RCC and clinicopathological characteristics. Final analysis of 1203 patients with RCC from 14 eligible studies was performed. RESULTS: We observed that CXCR4 expression is significantly higher in RCC than in normal renal tissue, and the pooled OR from 7 studies including 435 RCC and 297 normal renal tissues was OR = 46.23, 95% CI = 7.18-297.69, p < 0.0001. CXCR4 expression is not associated with gender status and clinical stages. However, CXCR4 expression was significantly associated with pathological grades, metastatic status, and overall survival in patients with RCC. DISCUSSION: These results indicate that CXCR4 expression is associated with increased risk, progression, and prognosis for patients with RCC. The determination of CXCR4 expression may provide a biomarker for tumor risk evaluation, progression, and prognosis of patients with RCC.


Assuntos
Carcinoma de Células Renais/genética , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/genética , Neoplasias Renais/mortalidade , Receptores CXCR4/metabolismo , Biomarcadores Tumorais/metabolismo , Feminino , Humanos , Masculino , Prognóstico , Fatores de Risco , Fatores Sexuais
18.
Appl Environ Microbiol ; 85(19)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31375484

RESUMO

The exact roles of various granule-associated proteins (GAPs) of polyhydroxybutyrate (PHB) are poorly investigated, particularly for bacteria associated with plants. In this study, four structural GAPs, named phasins PhaP1 to PhaP4, were identified and demonstrated as true phasins colocalized with PHB granules in Sinorhizobium fredii NGR234, a facultative microsymbiont of Vigna unguiculata and many other legumes. The conserved PhaP2 dominated in regulation of granule size under both free-living and symbiotic conditions. PhaP1, another conserved phasin, made a higher contribution than accessory phasins PhaP4 and PhaP3 to PHB biosynthesis at stationary phase. PhaP3, with limited phyletic distribution on the symbiosis plasmid of Sinorhizobium, was more important than PhaP1 in regulating PHB biosynthesis in V. unguiculata nodules. Under the test conditions, no significant symbiotic defects were observed for mutants lacking individual or multiple phaP genes. The mutant lacking two PHB synthases showed impaired symbiotic performance, while mutations in individual PHB synthases or a PHB depolymerase yielded no symbiotic defects. This phenomenon is not related to either the number or size of PHB granules in test mutants within nodules. Distinct metabolic profiles and cocktail pools of GAPs of different phaP mutants imply that core and accessory phasins can be differentially involved in regulating other cellular processes in the facultative microsymbiont S. fredii NGR234.IMPORTANCE Polyhydroxybutyrate (PHB) granules are a store of carbon and energy in bacteria and archaea and play an important role in stress adaptation. Recent studies have highlighted distinct roles of several granule-associated proteins (GAPs) in regulating the size, number, and localization of PHB granules in free-living bacteria, though our knowledge of the role of GAPs in bacteria associated with plants is still limited. Here we report distinct roles of core and accessory phasins associated with PHB granules of Sinorhizobium fredii NGR234, a broad-host-range microsymbiont of diverse legumes. Core phasins PhaP2 and PhaP1 are conserved major phasins in free-living cells. PhaP2 and accessory phasin PhaP3, encoded by an auxiliary gene on the symbiosis plasmid, are major phasins in nitrogen-fixing bacteroids in cowpea nodules. GAPs and metabolic profiles can vary in different phaP mutants. Contrasting symbiotic performances between mutants lacking PHB synthases, depolymerase, or phasins were revealed.


Assuntos
Fabaceae/microbiologia , Regulação Bacteriana da Expressão Gênica , Hidroxibutiratos/metabolismo , Lectinas de Plantas/genética , Sinorhizobium fredii/genética , Simbiose , Proteínas de Bactérias/genética , Grânulos Citoplasmáticos/metabolismo , Sinorhizobium fredii/metabolismo , Vigna/microbiologia
19.
Sci Adv ; 5(8): eaav9801, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31457079

RESUMO

A parasite-infected host may promote performance of associated insect vectors; but possible parasite effects on nonvector insects have been largely unexplored. Here, we show that Begomovirus, the largest genus of plant viruses and transmitted exclusively by whitefly, reprogram plant immunity to promote the fitness of the vector and suppress performance of nonvector insects (i.e., cotton bollworm and aphid). Infected plants accumulated begomoviral ßC1 proteins in the phloem where they were bound to the plant transcription factor WRKY20. This viral hijacking of WRKY20 spatiotemporally redeployed plant chemical immunity within the leaf and had the asymmetrical benefiting effects on the begomoviruses and its whitefly vectors while negatively affecting two nonvector competitors. This type of interaction between a parasite and two types of herbivores, i.e., vectors and nonvectors, occurs widely in various natural and agricultural ecosystems; thus, our results have broad implications for the ecological significance of parasite-vector-host tripartite interactions.


Assuntos
Herbivoria , Interações Hospedeiro-Parasita , Insetos/fisiologia , Imunidade Vegetal , Plantas/imunologia , Plantas/parasitologia , Plantas/virologia , Animais , Begomovirus , Hemípteros , Insetos Vetores , Doenças das Plantas/parasitologia , Transdução de Sinais
20.
PLoS Pathog ; 15(6): e1007897, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31206553

RESUMO

Pandemics of vector-borne human and plant diseases often depend on the behaviors of their arthropod vectors. Arboviruses, including many bunyaviruses, manipulate vector behavior to accelerate their own transmission to vertebrates, birds, insects, and plants. However, the molecular mechanism underlying this manipulation remains elusive. Here, we report that the non-structural protein NSs of Tomato spotted wilt orthotospovirus, a prototype of the Tospoviridae family and the Orthotospovirus genus, is a key viral factor that indirectly modifies vector preference and increases vector performance. NSs suppresses the biosynthesis of plant volatile monoterpenes, which serve as repellents of the vector western flower thrips (WFT, Frankliniella occidentalis). NSs directly interacts with MYC2, the jasmonate (JA) signaling master regulator and its two close homologs MYC3 and MYC4, to disable JA-mediated activation of terpene synthase genes. The dysfunction of the MYCs subsequently attenuates host defenses, increases the attraction of thrips, and improves thrips fitness. Moreover, MYC2 associated with NSs of Tomato zonate spot orthotospovirus, another Euro/Asian-type orthotospovirus, suggesting that MYC2 is an evolutionarily conserved target of Orthotospovirus species for suppression of terpene-based resistance to promote vector performance. These findings elucidate the molecular mechanism through which an orthotospovirus indirectly manipulates vector behaviors and therefore facilitates pathogen transmission. Our results provide insights into the molecular mechanisms by which Orthotospovirus NSs counteracts plant immunity for pathogen transmission.


Assuntos
Bunyaviridae/metabolismo , Ciclopentanos/metabolismo , Lycopersicon esculentum , Oxilipinas/metabolismo , Proteínas de Plantas/metabolismo , Vírus de Plantas/metabolismo , Transdução de Sinais , Tisanópteros/fisiologia , Fatores de Transcrição/metabolismo , Proteínas não Estruturais Virais/metabolismo , Animais , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/parasitologia , Lycopersicon esculentum/virologia , Terpenos/metabolismo
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