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1.
Plant Mol Biol ; 112(3): 161-177, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37226022

RESUMO

Plants defend themselves against pathogens using a two-layered immune system. The first response, pattern-triggered immunity (PTI), is activated upon recognition of microbe-associated molecular patterns (MAMPs). Virulent bacteria such as Pseudomonas syringae pv. tomato (Pst), deliver effector proteins into the plant cell to promote susceptibility. However, some plants possess resistance (R) proteins that recognize specific effectors leading to the activation of the second response, effector-triggered immunity (ETI). Resistant tomatoes such as Río Grande-PtoR recognize two Pst effectors (AvrPto and AvrPtoB) through the host Pto/Prf complex and activate ETI. We previously showed that the transcription factors (TF) WRKY22 and WRKY25 are positive regulators of plant immunity against bacterial and potentially non-bacterial pathogens in Nicotiana benthamiana. Here, the CRISPR-Cas9 technique was used to develop three knockout tomato lines for either one or both TFs. The single and double mutants were all compromised in Pto/Prf-mediated ETI and had a weaker PTI response. The stomata apertures in all of the mutant lines did not respond to darkness or challenge with Pst DC3000. The WRKY22 and WRKY25 proteins both localize in the nucleus, but we found no evidence of a physical interaction between them. The WRKY22 TF was found to be involved in the transcriptional regulation of WRKY25, supporting the idea that they are not functionally redundant. Together, our results indicate that both WRKY TFs play a role in modulating stomata and are positive regulators of plant immunity in tomato.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Pseudomonas syringae/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Plantas/metabolismo , Mutação , Imunidade Vegetal/genética , Doenças das Plantas/microbiologia
2.
J Biol Chem ; 299(1): 102726, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410438

RESUMO

The characterization of protein-protein interactions (PPIs) is of high value for understanding protein function. Two strategies are popular for identification of PPIs direct from the cellular environment: affinity capture (pulldown) isolates the protein of interest with an immobilized matrix that specifically captures the target and potential partners, whereas in BioID, genetic fusion of biotin ligase facilitates proximity biotinylation, and labeled proteins are isolated with streptavidin. Whilst both methods provide valuable insights, they can reveal distinct PPIs, but the basis for these differences is less obvious. Here, we compare both methods using four different trypanosome proteins as baits: poly(A)-binding proteins PABP1 and PABP2, mRNA export receptor MEX67, and the nucleoporin NUP158. With BioID, we found that the population of candidate interacting proteins decreases with more confined bait protein localization, but the candidate population is less variable with affinity capture. BioID returned more likely false positives, in particular for proteins with less confined localization, and identified low molecular weight proteins less efficiently. Surprisingly, BioID for MEX67 identified exclusively proteins lining the inner channel of the nuclear pore complex (NPC), consistent with the function of MEX67, whereas the entire NPC was isolated by pulldown. Similarly, for NUP158, BioID returned surprisingly few PPIs within NPC outer rings that were by contrast detected with pulldown but instead returned a larger cohort of nuclear proteins. These rather significant differences highlight a clear issue with reliance on a single method to identify PPIs and suggest that BioID and affinity capture are complementary rather than alternative approaches.


Assuntos
Proteínas , Proteômica , Biotinilação , Poro Nuclear , Proteínas/química , Proteômica/métodos , Estreptavidina/química
3.
Clin Transl Oncol ; 25(3): 803-816, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36510038

RESUMO

INTRODUCTION: GEO- and TCGA-based data analysis suggested the differential expression of miR-29c in pancreatic cancer. However, limited data are available on the downstream mechanistic actions of miR-29c, which may fuel the in vitro and in vivo studies of pancreatic cancer. METHODS: The downstream target gene of miR-29c and the downstream ERK/MAPK pathway involved in pancreatic cancer were predicted by bioinformatics tools. Next, the expression of miR-29c and MAPK1 was determined in pancreatic cancer tissues and cells. After ectopic expression and depletion experiments in pancreatic cancer cells, oncogenic phenotypes of pancreatic cancer cells were tested by MTS assay, Transwell assay, and flow cytometry. Effects of miR-29c/MAPK1 on tumorigenic ability in vivo were evaluated in pancreatic cancer xenografts in nude mice. RESULTS: Through differential analysis, five pancreatic cancer-related miRNAs (hsa-miR-29c, hsa-miR-107, hsa-miR-324-3p, hsa-miR-375, and hsa-miR-210) were screened out, among which miR-29c was selected as the key miRNA related to prognosis of pancreatic cancer patients. miR-29c could target and inhibit MAPK1 to suppress the activation of ERK/MAPK pathway. miR-29c was downregulated in pancreatic cancer, and its high expression was related to the good prognosis of pancreatic cancer patients. Both in vitro and in vivo experiments demonstrated that restoration of miR-29c inhibited oncogenic phenotypes of pancreatic cancer cells, as well as repressed tumorigenic ability of pancreatic cancer cells in nude mice. CONCLUSIONS: Taken together, we unveil a novel miR-29c/MAPK1/ERK/MAPK axis that suppresses pancreatic cancer both in vitro and in vivo.


Assuntos
MicroRNAs , Neoplasias Pancreáticas , Camundongos , Animais , Humanos , Camundongos Nus , Linhagem Celular Tumoral , MicroRNAs/metabolismo , Neoplasias Pancreáticas/genética , Regulação Neoplásica da Expressão Gênica , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Neoplasias Pancreáticas
4.
Front Mol Biosci ; 9: 971811, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275617

RESUMO

Gene expression in pathogenic protozoans of the family Trypanosomatidae has several novel features, including multiple eIF4F-like complexes involved in protein synthesis. The eukaryotic eIF4F complex, formed mainly by eIF4E and eIF4G subunits, is responsible for the canonical selection of mRNAs required for the initiation of mRNA translation. The best-known complexes implicated in translation in trypanosomatids are based on two related pairs of eIF4E and eIF4G subunits (EIF4E3/EIF4G4 and EIF4E4/EIF4G3), whose functional distinctions remain to be fully described. Here, to define interactomes associated with both complexes in Trypanosoma brucei procyclic forms, we performed parallel immunoprecipitation experiments followed by identification of proteins co-precipitated with the four tagged eIF4E and eIF4G subunits. A number of different protein partners, including RNA binding proteins and helicases, specifically co-precipitate with each complex. Highlights with the EIF4E4/EIF4G3 pair include RBP23, PABP1, EIF4AI and the CRK1 kinase. Co-precipitated partners with the EIF4E3/EIF4G4 pair are more diverse and include DRBD2, PABP2 and different zinc-finger proteins and RNA helicases. EIF4E3/EIF4G4 are essential for viability and to better define their role, we further investigated their phenotypes after knockdown. Depletion of either EIF4E3/EIF4G4 mRNAs lead to aberrant morphology with a more direct impact on events associated with cytokinesis. We also sought to identify those mRNAs differentially associated with each complex through CLIP-seq with the two eIF4E subunits. Predominant among EIF4E4-bound transcripts are those encoding ribosomal proteins, absent from those found with EIF4E3, which are generally more diverse. RNAi mediated depletion of EIF4E4, which does not affect proliferation, does not lead to changes in mRNAs or proteins associated with EIF4E3, confirming a lack of redundancy and distinct roles for the two complexes.

5.
Clinics (Sao Paulo) ; 76: e2355, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33567047

RESUMO

OBJECTIVES: To evaluate the efficacy of autologous platelet-rich plasma (PRP) gel in the treatment of refractory pressure injuries and its effect on wound healing time and quality of life of patients. METHODS: A random number table method was used to group 102 patients with refractory pressure injuries into either a control group (CG) (51 cases) receiving negative pressure wound therapy (NPWT) or a study group (SG) (51 cases) receiving NPWT+PRP gel. RESULTS: The total efficacy rate in the SG (92.16%) was higher than that in the CG (76.47%) (p<0.05). The SG exhibited lower visual analog scale (VAS) scores and pressure ulcer scale for healing (PUSH) scores, smaller wound sizes and depths, and shorter wound healing times than the CG after 21 days of treatment (p<0.05). After 6 months of treatment, the SG scored higher than the CG on the psychological, physiological, social functions, and daily activity domains on the World Health Organization Quality of Life (WHOQOL-BREF) scale (p<0.05). The incidence of postoperative complications in the SG (13.73%) was not significantly different from that of the CG (7.84%) (p>0.05). CONCLUSION: In the treatment of refractory pressure injuries, PRP gel can accelerate wound healing, reduce wound pain, shorten the treatment cycle, regulate tissue inhibitor matrix metalloproteinase-1 (TIMP-1) and matrix metalloproteinase-9 (MMP-9) levels and the expression of specific proteins in granulation tissue, reduce the levels of the inflammatory factors interleukin-1ß (IL-1ß), IL-8, and tumor necrosis factor-α (TNF-α), and improve the quality of life of patients without increasing complications.


Assuntos
Tratamento de Ferimentos com Pressão Negativa , Plasma Rico em Plaquetas , Úlcera por Pressão , Humanos , Qualidade de Vida , Cicatrização
6.
Clinics ; 76: e2355, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1153933

RESUMO

OBJECTIVES: To evaluate the efficacy of autologous platelet-rich plasma (PRP) gel in the treatment of refractory pressure injuries and its effect on wound healing time and quality of life of patients. METHODS: A random number table method was used to group 102 patients with refractory pressure injuries into either a control group (CG) (51 cases) receiving negative pressure wound therapy (NPWT) or a study group (SG) (51 cases) receiving NPWT+PRP gel. RESULTS: The total efficacy rate in the SG (92.16%) was higher than that in the CG (76.47%) (p<0.05). The SG exhibited lower visual analog scale (VAS) scores and pressure ulcer scale for healing (PUSH) scores, smaller wound sizes and depths, and shorter wound healing times than the CG after 21 days of treatment (p<0.05). After 6 months of treatment, the SG scored higher than the CG on the psychological, physiological, social functions, and daily activity domains on the World Health Organization Quality of Life (WHOQOL-BREF) scale (p<0.05). The incidence of postoperative complications in the SG (13.73%) was not significantly different from that of the CG (7.84%) (p>0.05). CONCLUSION: In the treatment of refractory pressure injuries, PRP gel can accelerate wound healing, reduce wound pain, shorten the treatment cycle, regulate tissue inhibitor matrix metalloproteinase-1 (TIMP-1) and matrix metalloproteinase-9 (MMP-9) levels and the expression of specific proteins in granulation tissue, reduce the levels of the inflammatory factors interleukin-1β (IL-1β), IL-8, and tumor necrosis factor-α (TNF-α), and improve the quality of life of patients without increasing complications.


Assuntos
Humanos , Úlcera por Pressão , Plasma Rico em Plaquetas , Tratamento de Ferimentos com Pressão Negativa , Qualidade de Vida , Cicatrização
7.
Risk Anal ; 40(8): 1612-1631, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32450007

RESUMO

Hydrometeorological phenomena have increased in intensity and frequency in last decades, with Europe as one of the most affected areas. This accounts for considerable economic losses in the region. Regional adaptation strategies for costs minimization require a comprehensive assessment of the disasters' economic impacts at a multiple-region scale. This article adapts the flood footprint method for multiple-region assessment of total economic impact and applies it to the 2009 Central European Floods event. The flood footprint is an impact accounting framework based on the input-output methodology to economically assess the physical damage (direct) and production shortfalls (indirect) within a region and wider economic networks, caused by a climate disaster. Here, the model is extended through the capital matrix, to enable diverse recovery strategies. According to the results, indirect losses represent a considerable proportion of the total costs of a natural disaster, and most of them occur in nonhighly directly impacted industries. For the 2009 Central European Floods, the indirect losses represent 65% out of total, and 70% of it comes from four industries: business services, manufacture general, construction, and commerce. Additionally, results show that more industrialized economies would suffer more indirect losses than less-industrialized ones, in spite of being less vulnerable to direct shocks. This may link to their specific economic structures of high capital-intensity and strong interindustrial linkages.


Assuntos
Inundações , Risco , Mudança Climática , Europa (Continente)
8.
Braz J Med Biol Res ; 52(12): e8754, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826180

RESUMO

Cuscuta chinensis Lam. (Convolvulaceae) is an important herbal medicine widely used to improve sexual function, treat osteoporosis, and prevent aging, and has been reported to exhibit anti-osteoporotic effects in vitro. However, the activity of Cuscuta chinensis Lam. on glucocorticoid-induced osteoporosis still remains unclear. The present study aimed to assess the protective effect and the underlying mechanism of action of Cuscuta chinensis extract (CCE) against glucocorticoid-induced osteoporosis in vivo. Sprague-Dawley rats were randomly divided into four groups as follows: control group, osteoporosis group, and 2 CCE-treated osteoporosis groups (100 mg·kg-1·day-1). Blood samples and femur bones were collected for immunohistochemistry, biochemical, mRNA expression, and western blot analysis. HPLC analysis revealed that chlorogenic acid, quercetin, and hyperin were the major constituents of CCE. The results indicated that CCE increased bone length, bone weight, and bone mineral density and suppressed dexamethasone (DEX)-induced reduction in body weight. In addition, TRAP staining indicated that CCE reduced osteoclasts in DEX-induced osteoporosis rats. Mechanistically, CCE treatment alleviated the increase of bone resorption markers and the decline of osteogenic markers, which might be partially mediated by regulation of RANKL/OPG and RunX2 pathways. These results suggest that CCE showed promising effects in the protection against glucocorticoid-induced osteoporosis through protecting osteoblasts and suppressing osteoclastogenesis.


Assuntos
Cuscuta/química , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Osteoporose/prevenção & controle , Osteoprotegerina/metabolismo , Extratos Vegetais/farmacologia , Ligante RANK/metabolismo , Animais , Western Blotting , Densidade Óssea/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Imuno-Histoquímica , Osteoporose/induzido quimicamente , Osteoprotegerina/efeitos dos fármacos , Ligante RANK/efeitos dos fármacos , RNA Mensageiro , Ratos , Ratos Sprague-Dawley
10.
Braz. j. med. biol. res ; 52(12): e8754, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1055467

RESUMO

Cuscuta chinensis Lam. (Convolvulaceae) is an important herbal medicine widely used to improve sexual function, treat osteoporosis, and prevent aging, and has been reported to exhibit anti-osteoporotic effects in vitro. However, the activity of Cuscuta chinensis Lam. on glucocorticoid-induced osteoporosis still remains unclear. The present study aimed to assess the protective effect and the underlying mechanism of action of Cuscuta chinensis extract (CCE) against glucocorticoid-induced osteoporosis in vivo. Sprague-Dawley rats were randomly divided into four groups as follows: control group, osteoporosis group, and 2 CCE-treated osteoporosis groups (100 mg·kg-1·day-1). Blood samples and femur bones were collected for immunohistochemistry, biochemical, mRNA expression, and western blot analysis. HPLC analysis revealed that chlorogenic acid, quercetin, and hyperin were the major constituents of CCE. The results indicated that CCE increased bone length, bone weight, and bone mineral density and suppressed dexamethasone (DEX)-induced reduction in body weight. In addition, TRAP staining indicated that CCE reduced osteoclasts in DEX-induced osteoporosis rats. Mechanistically, CCE treatment alleviated the increase of bone resorption markers and the decline of osteogenic markers, which might be partially mediated by regulation of RANKL/OPG and RunX2 pathways. These results suggest that CCE showed promising effects in the protection against glucocorticoid-induced osteoporosis through protecting osteoblasts and suppressing osteoclastogenesis.


Assuntos
Animais , Ratos , Osteoporose/prevenção & controle , Dexametasona/farmacologia , Extratos Vegetais/farmacologia , Cuscuta/química , Osteoprotegerina/metabolismo , Glucocorticoides/farmacologia , Osteoporose/induzido quimicamente , RNA Mensageiro , Imuno-Histoquímica , Densidade Óssea/efeitos dos fármacos , Western Blotting , Cromatografia Líquida de Alta Pressão , Ratos Sprague-Dawley , Ligante RANK/efeitos dos fármacos , Ligante RANK/metabolismo , Osteoprotegerina/efeitos dos fármacos
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