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1.
BMC Plant Biol ; 24(1): 458, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38797860

RESUMO

BACKGROUND: The endosperm serves as the primary source of nutrients for maize (Zea mays L.) kernel embryo development and germination. Positioned at the base of the endosperm, the transfer cells (TCs) of the basal endosperm transfer layer (BETL) generate cell wall ingrowths, which enhance the connectivity between the maternal plant and the developing kernels. These TCs play a crucial role in nutrient transport and defense against pathogens. The molecular mechanism underlying BETL development in maize remains unraveled. RESULTS: This study demonstrated that the MYB-related transcription factor ZmMYBR29, exhibited specific expression in the basal cellularized endosperm, as evidenced by in situ hybridization analysis. Utilizing the CRISPR/Cas9 system, we successfully generated a loss-of-function homozygous zmmybr29 mutant, which presented with smaller kernel size. Observation of histological sections revealed abnormal development and disrupted morphology of the cell wall ingrowths in the BETL. The average grain filling rate decreased significantly by 26.7% in zmmybr29 mutant in comparison to the wild type, which impacted the dry matter accumulation within the kernels and ultimately led to a decrease in grain weight. Analysis of RNA-seq data revealed downregulated expression of genes associated with starch synthesis and carbohydrate metabolism in the mutant. Furthermore, transcriptomic profiling identified 23 genes that expressed specifically in BETL, and the majority of these genes exhibited altered expression patterns in zmmybr29 mutant. CONCLUSIONS: In summary, ZmMYBR29 encodes a MYB-related transcription factor that is expressed specifically in BETL, resulting in the downregulation of genes associated with kernel development. Furthermore, ZmMYBR29 influences kernels weight by affecting the grain filling rate, providing a new perspective for the complementation of the molecular regulatory network in maize endosperm development.


Assuntos
Grão Comestível , Endosperma , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Fatores de Transcrição , Zea mays , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Grão Comestível/genética , Grão Comestível/crescimento & desenvolvimento , Grão Comestível/metabolismo , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Endosperma/metabolismo , Parede Celular/metabolismo , Parede Celular/genética , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sistemas CRISPR-Cas
2.
Proc Natl Acad Sci U S A ; 118(39)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34548401

RESUMO

IRON MAN (IMA) peptides, a family of small peptides, control iron (Fe) transport in plants, but their roles in Fe signaling remain unclear. BRUTUS (BTS) is a potential Fe sensor that negatively regulates Fe homeostasis by promoting the ubiquitin-mediated degradation of bHLH105 and bHLH115, two positive regulators of the Fe deficiency response. Here, we show that IMA peptides interact with BTS. The C-terminal parts of IMA peptides contain a conserved BTS interaction domain (BID) that is responsible for their interaction with the C terminus of BTS. Arabidopsis thaliana plants constitutively expressing IMA genes phenocopy the bts-2 mutant. Moreover, IMA peptides are ubiquitinated and degraded by BTS. bHLH105 and bHLH115 also share a BID, which accounts for their interaction with BTS. IMA peptides compete with bHLH105/bHLH115 for interaction with BTS, thereby inhibiting the degradation of these transcription factors by BTS. Genetic analyses suggest that bHLH105/bHLH115 and IMA3 have additive roles and function downstream of BTS. Moreover, the transcription of both BTS and IMA3 is activated directly by bHLH105 and bHLH115 under Fe-deficient conditions. Our findings provide a conceptual framework for understanding the regulation of Fe homeostasis: IMA peptides protect bHLH105/bHLH115 from degradation by sequestering BTS, thereby activating the Fe deficiency response.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Homeostase , Ferro/metabolismo , Fragmentos de Peptídeos/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética
3.
J Exp Bot ; 74(8): 2754-2767, 2023 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-36787175

RESUMO

Iron (Fe) is an essential trace element for plants. When suffering from Fe deficiency, plants modulate the expression of Fe deficiency-responsive genes to promote Fe uptake. POPEYE (PYE) is a key bHLH (basic helix-loop-helix) transcription factor involved in Fe homeostasis. However, the molecular mechanism of PYE regulating the Fe deficiency response remains elusive in Arabidopsis. We found that the overexpression of PYE attenuates the expression of Fe deficiency-responsive genes. PYE directly represses the transcription of bHLH Ib genes (bHLH38, bHLH39, bHLH100, and bHLH101) by associating with their promoters. Although PYE contains an ethylene response factor-associated amphiphilic repression (EAR) motif, it does not interact with the transcriptional co-repressors TOPLESS/TOPLESS-RELATED (TPL/TPRs). Sub-cellular localization analysis indicated that PYE localizes in both the cytoplasm and nucleus. PYE contains a nuclear export signal (NES) which is required for the cytoplasmic localization of PYE. Mutation of the NES amplifies the repression function of PYE, resulting in down-regulation of Fe deficiency-responsive genes. Co-expression assays indicated that three bHLH IVc members (bHLH104, bHLH105/ILR3, and bHLH115) facilitate the nuclear accumulation of PYE. Conversely, PYE indirectly represses the transcription activation ability of bHLH IVc. Additionally, PYE directly negatively regulates its own transcription. This study provides new insights into the Fe deficiency response signalling pathway and enhances the understanding of PYE functions in Arabidopsis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase/genética , Ferro/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Angew Chem Int Ed Engl ; 62(31): e202304033, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37263979

RESUMO

The development of novel polymerization capable of yielding polymers with low molecular weight distribution (D) is essential and significant in polymer chemistry, where monofunctional initiator contains only one initiation site in these polymerizations generally. Here, ketyl radical anion species is introduced to develop a novel Ketyl Mediated Polymerization (KMP), which enables radical polymerization at carbon radical site and anionic ring-opening polymerization at oxygen anion site, respectively. Meanwhile, polymerization and corresponding organic synthesis generally couldn't be performed simultaneously in one pot. Through KMP, organic synthesis and polymerization are achieved in one pot, where small molecules (cyclopentane derivates) and polymers with low D are successfully prepared under mild condition simultaneously. At the initiation step, both organic synthesis and polymerization are initiated by single electron transfer reaction with ketyl radical anion formation. Cyclopentane derivates are synthesized through 3-3 coupling reaction and cyclization. Polystyrene and polycaprolactone with low D and a full monomer conversion are prepared by KMP via radical polymerization and anionic ring-opening polymerization, respectively. This work therefore enables both organic synthesis and two different polymerizations from same initiation system, which saves time, labour, resource and energy and expands the reaction mode and method libraries of organic chemistry and polymer chemistry.

5.
Gastroenterology ; 160(3): 941-945.e8, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33197449

RESUMO

The increasing incidence of primary and recurring Clostridioides difficile infections (CDI), which evade current treatment strategies, reflects the changing biology of C difficile. Here, we describe a putative plasmid-mediated mechanism potentially driving decreased sensitivity of C difficile to vancomycin treatment. We identified a broad host range transferable plasmid in a C difficile strain associated with lack of adequate response to vancomycin treatment. The transfer of this plasmid to a vancomycin-susceptible C difficile isolate decreased its susceptibility to vancomycin in vitro and resulted in more severe disease in a humanized mouse model. Our findings suggest plasmid acquisition in the gastrointestinal tract to be a possible mechanism underlying vancomycin treatment failure in patients with CDI, but further work is needed to characterize the mechanism by which plasmid genes determine vancomycin susceptibility in C difficile.


Assuntos
Antibacterianos/farmacologia , Clostridioides difficile/genética , Infecções por Clostridium/tratamento farmacológico , Plasmídeos/genética , Vancomicina/farmacologia , Animais , Antibacterianos/uso terapêutico , Clostridioides difficile/efeitos dos fármacos , Clostridioides difficile/isolamento & purificação , Infecções por Clostridium/microbiologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana/genética , Vida Livre de Germes , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Plasmídeos/isolamento & purificação , Vancomicina/uso terapêutico , Sequenciamento Completo do Genoma
6.
Clin Infect Dis ; 72(5): 806-813, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32064535

RESUMO

BACKGROUND: Current approaches in tracking Clostridioides difficile infection (CDI) and individualizing patient management are incompletely defined. METHODS: We recruited 468 subjects with CDI at Mayo Clinic Rochester between May and December 2016 and performed whole-genome sequencing (WGS) on C. difficile isolates from 397. WGS was also performed on isolates from a subset of the subjects at the time of a recurrence of infection. The sequence data were analyzed by determining core genome multilocus sequence type (cgMLST), with isolates grouped by allelic differences and the predicted ribotype. RESULTS: There were no correlations between C. difficile isolates based either on cgMLST or ribotype groupings and CDI outcome. An epidemiologic assessment of hospitalized subjects harboring C. difficile isolates with ≤2 allelic differences, based on standard infection prevention and control assessment, revealed no evidence of person-to-person transmission. Interestingly, community-acquired CDI subjects in 40% of groups with ≤2 allelic differences resided within the same zip code. Among 18 subjects clinically classified as having recurrent CDI, WGS revealed 14 with initial and subsequent isolates differing by ≤2 allelic differences, suggesting a relapse of infection with the same initial strain, and 4 with isolates differing by >50 allelic differences, suggesting reinfection. Among the 5 subjects classified as having a reinfection based on the timing of recurrence, 3 had isolates with ≤2 allelic differences between them, suggesting a relapse, and 2 had isolates differing by >50 allelic differences, suggesting reinfection. CONCLUSIONS: Our findings point to potential transmission of C. difficile in the community. WGS better differentiates relapse from reinfection than do definitions based on the timing of recurrence.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Clostridioides , Clostridioides difficile/genética , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/epidemiologia , Humanos , Recidiva , Reinfecção , Ribotipagem
7.
J Bacteriol ; 202(24)2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32868403

RESUMO

Motility is required for many bacterial pathogens to reach and colonize target sites. Vibrio cholerae traverses a thick mucus barrier coating the small intestine to reach the underlying epithelium. We screened a transposon library in motility medium containing mucin to identify factors that influence mucus transit. Lesions in structural genes of the type VI secretion system (T6SS) were among those recovered. Two-dimensional (2D) and 3D single-cell tracking was used to compare the motility behaviors of wild-type cells and a mutant that collectively lacked three essential T6SS structural genes (T6SS-). In the absence of mucin, wild-type and T6SS- cells exhibited similar speeds and run-reverse-flick (RRF) swimming patterns, in which forward-moving cells briefly backtrack before stochastically reorienting (flicking) in a new direction upon resuming forward movement. We show that mucin induced T6SS expression and activity in wild-type bacteria but significantly decreased their swimming speed and flicking, yielding curvilinear or near-surface circular traces for many cells. Conversely, mucin slowed T6SS- cells to a lesser extent, and many continued to flick and produce RRF-like traces. ΔcheY3 cells, which exclusively swim in the forward direction and thus cannot flick, also produced curvilinear traces with or without mucin present and, on occasion, near-surface circular traces in the presence of mucin. The dependence of flicking on swimming speed suggested that mucin-induced T6SS activity further decreased V. cholerae motility and thereby reduced flicking probability during reverse-to-forward transitions. We propose that this encourages cells to continue on their current trajectory rather than reorienting, which may benefit those tracking toward the epithelial surface.IMPORTANCEV. cholerae deploys an arsenal of virulence factors as it attempts to traverse a protective mucus layer and reach the epithelial surface of the distal small intestine. The T6SS used to cull bacterial competition during infection is induced by mucus. We show that this activity may serve an additional purpose by further decreasing motility in the presence of mucin, thereby reducing the probability of speed-dependent, near-perpendicular directional changes. We posit that this encourages cells to maintain course rather than change direction, which may aid those attempting to reach and colonize the epithelial surface.


Assuntos
Proteínas de Bactérias/metabolismo , Cólera/microbiologia , Mucinas/metabolismo , Sistemas de Secreção Tipo VI/metabolismo , Vibrio cholerae/citologia , Vibrio cholerae/metabolismo , Proteínas de Bactérias/genética , Cólera/metabolismo , Regulação Bacteriana da Expressão Gênica , Humanos , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Sistemas de Secreção Tipo VI/genética , Vibrio cholerae/genética
8.
Environ Microbiol ; 22(10): 4167-4182, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31355512

RESUMO

The opportunistic human pathogen Vibrio vulnificus inhabits warm coastal waters and asymptomatically colonizes seafood, most commonly oysters. We previously characterized an isolate that exhibited greater biofilm formation, aggregation and oyster colonization than its parent. This was due, in part, to the production of a Type IV Tad pilus (Iam). However, the locus lacked key processing and regulatory genes required for pilus production. Here, we identify a pilin peptidase iamP, and LysR-type regulator (LRTR) iamR, that fulfil these roles and show that environmental calcium, which oysters enrich for shell repair and growth, regulates iam expression. The architecture of the iam locus differs from the classical LRTR paradigm and requires an additional promoter to be integrated into the regulatory network. IamR specifically recognized the iamR promoter (PiamR ) and the intergenic iamP-iamA region (PiamP-A ). PiamR exhibited classical negative auto-regulation but, strikingly, IamR inversely regulated the divergent iamP and iamA promoters in a calcium-dependent manner. Moreover, expression of the c-di-GMP and calcium-regulated, biofilm-promoting brp exopolysaccharide was IamA-dependent. These results support a scenario in which the calcium-enriched oyster environment triggers IamP-mediated processing of prepilin amassed in the periplasm for rapid pilin elaboration and subsequent BRP production to promote colonization.


Assuntos
Proteínas de Fímbrias/genética , Ostreidae/microbiologia , Vibrio vulnificus/genética , Animais , Biofilmes/crescimento & desenvolvimento , Cálcio/metabolismo , GMP Cíclico/análogos & derivados , GMP Cíclico/metabolismo , Loci Gênicos , Ostreidae/metabolismo , Regiões Promotoras Genéticas , Vibrio vulnificus/fisiologia
9.
Environ Microbiol ; 20(2): 828-841, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29235706

RESUMO

Vibrio vulnificus has the highest death rate (>35%) and per-case economic burden ($3.3 million) of any foodborne pathogen in the United States. Infections occur via open wounds or following ingestion of contaminated seafood, most infamously oysters. We isolated a 1000th generation descendant, designated NT that exhibited increased biofilm and aggregate formation relative to its parent. We identified two significant causal changes underlying these phenotypes. First, the entire 24-kb capsular polysaccharide biosynthesis locus, which is essential for virulence but inhibits biofilm formation, had been purged from the genome. However, NT formed more extensive biofilms and aggregates than a defined cps mutant, suggesting that additional factor(s) contributed to its phenotypes. Second, the expression of a tight adherence (tad) pilus locus was elevated in NT. Deletion of the associated pilin (flp) decreased NT biofilm and aggregate formation. Furthermore, NTΔflp strains were deficient relative to NT in an oyster colonization model, demonstrating a positive correlation between the biofilm and aggregation phenotypes associated with Tad pilus production and efficient bacterial retention by feeding oysters. Despite being widely distributed in the Vibrionaceae, this is the first demonstration of a bona fide physiological role for a Tad pilus in this bacterial family.


Assuntos
Biofilmes/crescimento & desenvolvimento , Proteínas de Fímbrias/genética , Fímbrias Bacterianas/genética , Ostreidae/microbiologia , Polissacarídeos Bacterianos/genética , Vibrio vulnificus/crescimento & desenvolvimento , Vibrio vulnificus/genética , Animais , Fímbrias Bacterianas/metabolismo , Doenças Transmitidas por Alimentos/microbiologia , Genoma Bacteriano/genética , Fenótipo , Alimentos Marinhos/microbiologia , Virulência/genética
10.
J Bacteriol ; 199(19)2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28652300

RESUMO

Vibrio vulnificus is an estuarine bacterium and potent opportunistic human pathogen. It enters the food chain by asymptomatically colonizing a variety of marine organisms, most notably oysters. Expression of the brp-encoded extracellular polysaccharide, which enhances cell-surface adherence, is regulated by cyclic di-GMP (c-di-GMP) and the activator BrpT. The Vibrio cholerae and Vibrio parahaemolyticus homologs VpsT and CpsQ, directly bind c-di-GMP via a novel W[F/L/M][T/S]R motif, and c-di-GMP binding is absolutely required for activity. Notably, BrpT belongs to a distinct subclass of VpsT-like regulators that harbor a proline in the third position of the c-di-GMP binding motif (WLPR), and the impact of this change on activity is unknown. We show that the brp locus is organized as two linked operons with BrpT specifically binding to promoters upstream of brpA and brpH Expression data and structural modeling suggested that BrpT might be less dependent on c-di-GMP binding for activity than VpsT or CpsQ. We show that the affinity of BrpT for c-di-GMP is low and that signal binding is not a requisite for BrpT function. Furthermore, a BrpT mutant engineered to carry a canonical WLTR motif (BrpTP124T) bound c-di-GMP with high affinity and its activity was now c-di-GMP dependent. Conversely, introduction of the WLPR motif into VpsT suppressed its dependence on c-di-GMP for activity. This is the first demonstration of reduced dependence on signal association for regulator function within this motif family. Thus, BrpT defines a new class of VpsT-like transcriptional regulators, and the WLPR motif variant may similarly liberate the activity of other subclass members.IMPORTANCE A Vibrio genome may encode nearly 100 proteins that make, break, and bind c-di-GMP, underscoring its central role in the physiology of these bacteria. The activity of the biofilm regulators VpsT of V. cholerae and CpsQ of V. parahaemolyticus is regulated by the direct binding of c-di-GMP via a novel W[F/L/M][T/S]R motif. The V. vulnificus homolog, BrpT, bears an unusual WLPR variant and remains active at low intracellular c-di-GMP levels. This suggests that the WLPR motif may also liberate the activity of other members of this subclass. A single point mutation at the 3rd position of the motif was sufficient to moderate dependence on c-di-GMP binding for activator function, highlighting the simplicity with which complex bacterial signaling networks can be rewired.

11.
Tumour Biol ; 39(7): 1010428317709127, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28714366

RESUMO

Hepatocellular carcinoma is one of the most prevalent neoplasms and the leading cause of cancer-related mortality worldwide. Mitochondrial ribosomal protein S23 is encoded by a nuclear gene and participates in mitochondrial protein translation. Mitochondrial ribosomal protein S23 overexpression has been found in many types of cancer. In this study, we explored mitochondrial ribosomal protein S23 expression in primary hepatocellular carcinoma tissues compared with matched adjacent non-tumoral liver tissues using mitochondrial ribosomal protein S23 messenger RNA and protein levels collected from public databases and clinical samples. Immunohistochemistry was performed to analyze the relationship between mitochondrial ribosomal protein S23 and various clinicopathological features. The results indicated that mitochondrial ribosomal protein S23 was significantly overexpressed in hepatocellular carcinoma. High mitochondrial ribosomal protein S23 expression was correlated with the tumor size and tumor-metastasis-node stage. Moreover, patients with high mitochondrial ribosomal protein S23 expression levels presented poorer survival rates. Mitochondrial ribosomal protein S23 was an independent prognostic factor for survival, especially at the early stage of hepatocellular carcinoma. In addition, the downregulation of mitochondrial ribosomal protein S23 decreased the proliferation of hepatocellular carcinoma in vitro and in vivo. In conclusion, we verified for the first time that mitochondrial ribosomal protein S23 expression was upregulated in hepatocellular carcinoma. High mitochondrial ribosomal protein S23 levels can predict poor clinical outcomes in hepatocellular carcinoma, and this protein plays a key role in tumor proliferation. Therefore, mitochondrial ribosomal protein S23 may be a potential therapeutic target for hepatocellular carcinoma.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Proteínas Mitocondriais/genética , Proteínas Ribossômicas/genética , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico
12.
Acta Pharmacol Sin ; 38(5): 660-671, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28112179

RESUMO

Dicer1 is an enzyme essential for microRNA (miRNA) maturation. The loss of miRNAs resulted from Dicer1 deficiency greatly contributes to the progression of many diseases, including lipid dysregulation, but its role in hepatic accumulation of free cholesterol (FC) that is critical in the development of non-alcoholic steatohepatitis (NASH) remains elusive. In this study, we used the liver-specific Dicer1-knockout mice to identify the miRNAs involved in hepatic FC accumulation. In a widely used dietary NASH model, mice were fed a methionine-choline-deficient (MCD) diet for 3 weeks, which resulted in significant increase in hepatic FC levels as well as decrease of Dicer1 mRNA levels in livers. The liver-specific Dicer1-knockout induced hepatic FC accumulation at 5-6 weeks, accompanied by increased mRNA and protein levels of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), a rate-limiting enzyme of cholesterol synthesis in livers. Eleven predicted miRNAs were screened, revealing that miR-29a/b/c significantly suppressed HMGCR expression by targeting the HMGCR mRNA 3'-UTR. Overexpression of miR-29a in SMMC-7721 cells, a steatosis hepatic cell model, significantly decreased HMGCR expression and the FC level. Furthermore, the expression levels of miR-29a were inversely correlated with HMGCR expression levels in the MCD diet mouse model in vivo and in 2 steatosis hepatic cell models (SMMC-7721 and HL-7702 cells) in vitro. Our results show that Dicer1/miR-29/HMGCR axis contributes to hepatic free cholesterol accumulation in mouse NASH, and miR-29 may serve as an important regulator of hepatic cholesterol homeostasis. Thus, miR-29a could be utilized as a potential therapeutic target for the treatment of non-alcoholic fatty liver disease as well as for other liver diseases associated with FC accumulation.


Assuntos
Colesterol/metabolismo , RNA Helicases DEAD-box/deficiência , Hidroximetilglutaril-CoA Redutases/metabolismo , MicroRNAs/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Ribonuclease III/deficiência , Animais , RNA Helicases DEAD-box/metabolismo , Dieta/efeitos adversos , Técnicas de Inativação de Genes , Masculino , Metionina/deficiência , Camundongos , Hepatopatia Gordurosa não Alcoólica/metabolismo , RNA Mensageiro/metabolismo , Ribonuclease III/metabolismo
13.
Acta Pharmacol Sin ; 38(1): 110-119, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27641735

RESUMO

Previous studies have shown that microRNA-1304 (miR-1304) is dysregulated in certain types of cancers, including non-small cell lung cancer (NSCLC), and might be involved in tumor survival and/or growth. In this study we investigated the direct target of miR-1304 and its function in NSCLC in vitro. Human lung adenocarcinoma cell lines (A549 and NCI-H1975) were studied. The cell proliferation and survival were investigated via cell counting, MTT and colony-formation assays. Cell apoptosis and cell cycle were examined using annexin V-PE/7-AAD and PI staining assays, respectively. The dual-luciferase reporter assay was used to verify post-transcriptional regulation of heme oxygenase-1 (HO-1) by miR-1304. CRISPR/Cas9 was used to deplete endogenous miR-1304. Overexpression of MiR-1304 significantly decreased the number and viability of NSCLC cells and colony formation, and induced cell apoptosis and G0/G1 phase cell cycle arrest. HO-1 was demonstrated to be a direct target of miR-1304 in NSCLC cells. Restoration of HO-1 expression by hemin (20 µmol/L) abolished the inhibition of miR-1304 on cell growth and rescued miR-1304-induced apoptosis in A549 cells. Suppression of endogenous miR-1304 with anti-1304 significantly increased HO-1 expression and promoted cell growth and survival in A549 cells. In 17 human NSCLC tissue samples, miR-1304 expression was significantly decreased, while HO-1 expression was significantly increased as compared to normal lung tissues. MicroRNA-1304 is a tumor suppressor and HO-1 is its direct target in NSCLC. The results suggest the potential for miR-1304 as a therapeutic target for NSCLC.


Assuntos
Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Heme Oxigenase-1/antagonistas & inibidores , MicroRNAs/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Heme Oxigenase-1/metabolismo , Hemina/farmacologia , Humanos , MicroRNAs/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Ensaio Tumoral de Célula-Tronco , Regulação para Cima
14.
Cell Physiol Biochem ; 40(6): 1334-1344, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27997903

RESUMO

BACKGROUND/AIMS: Circular RNAs (circRNAs) are a special novel type of a stable, diverse and conserved noncoding RNA in mammalian cells. Particularly in cancer, circRNAs have been reported to be widely involved in the physiological/pathological process of life. However, it is unclear whether circRNAs are specifically involved in pancreatic ductal adenocarcinoma (PDAC). METHODS: We investigated the expression profile of circRNAs in six PDAC cancer samples and paired adjacent normal tissues using microarray. A high-throughput circRNA microarray was used to identify dysregulated circular RNAs in six PDAC patients. Bioinformatic analyses were applied to study these differentially expressed circRNAs. Furthermore, quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to confirm these results. RESULTS: We revealed and confirmed that a number of circRNAs were dysregulated, which suggests a potential role in pancreatic cancer. CONCLUSIONS: this study demonstrates that clusters of circRNAs are aberrantly expressed in PDAC compared with normal samples and provides new potential targets for the future treatment of PDAC and novel insights into PDAC biology.


Assuntos
Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Neoplasias Pancreáticas/genética , RNA/genética , Adulto , Idoso , Sequência de Bases , Feminino , Ontologia Genética , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Anotação de Sequência Molecular , RNA/metabolismo , RNA Circular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Transdução de Sinais/genética
15.
Cell Physiol Biochem ; 36(1): 233-49, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25967963

RESUMO

BACKGROUND: The activation of tissue factor (TF) is one of the major reasons for coagulation dysregulation after pig-to-primate xenotransplantation. Tissue factor pathway inhibitor (TFPI) is the most important inhibitor of TF. Studies have demonstrated species incompatibility between pig TFPI and human TF. METHODS: A pig-to-macaque heterotopic auxiliary liver transplantation model was established to determine the origin of activated TF. Chimeric proteins of human and pig TFPI were constructed to assess the role of Kunitz domains in species incompatibility. Immortalised pig bone marrow mesenchymal stem cells transfected with human TFPI were tested for their ability to inhibit clotting in vitro. RESULTS: TF from recipient was activated early after liver xenotransplantation. Pig TFPI Kunitz domain 2 bound human FXa, but Kunitz domain 1 did not effectively inhibit human TF/FVIIa. Immortalised pig bone marrow mesenchymal cells (BMSCs) transfected with human TFPI showed a prolonged recalcification time in vitro and in a rodent model. CONCLUSION: Recipient TF is relevant to dysregulated coagulation after xenotransplantation. Kunitz domain 1 plays the most important role in species incompatibility between pig TFPI and human TF, and clotting can be inhibited by human TFPI-transfected pig BMSCs. Our study shows a possible way to resolve the incompatibility of pig TFPI.


Assuntos
Coagulação Sanguínea , Lipoproteínas/metabolismo , Fígado/metabolismo , Células-Tronco Mesenquimais/metabolismo , Tromboplastina/metabolismo , Animais , Células Cultivadas , Humanos , Técnicas In Vitro , Lipoproteínas/química , Lipoproteínas/genética , Transplante de Fígado , Macaca , Masculino , Transplante de Células-Tronco Mesenquimais , Modelos Animais , Estrutura Terciária de Proteína , Especificidade da Espécie , Suínos , Porco Miniatura , Tromboplastina/genética , Transplante Heterólogo , Transplante Heterotópico
16.
PLoS One ; 19(6): e0305822, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38917153

RESUMO

BACKGROUND: The relationship between plant-based diets and gallstone disease has been debated. This study aimed to shed light on the association between plant-based dietary index and the risk of developing gallstone disease. METHODS: Eligible participants were selected from National Health and Nutrition Examination Survey (NHANES) 2017-2020. Three plant-based diet indexes (PDI, healthy PDI, unhealthy PDI) were calculated using data from two NHANES 24-h dietary recall interviews. Restricted Cubic Spline and multivariate logistic regression were used to analyze the associations. Subgroup analysis was adopted to make the results more robust. RESULTS: A total of 5673 eligible participants were analyzed. After adjusting for various confounding variables, uPDI was positively associated with gallstone disease (OR = 1.53, 95%CI: 1.02-2.29). No association was found between PDI/hPDI and gallstone disease (p > 0.05). The results of subgroup analysis did not show any positive association between uPDI and gallstones in specific groups. CONCLUSION: Our study shows that the elevated uPDI are linked to a higher risk of gallstone disease.


Assuntos
Cálculos Biliares , Inquéritos Nutricionais , Humanos , Cálculos Biliares/epidemiologia , Feminino , Masculino , Estudos Transversais , Pessoa de Meia-Idade , Adulto , Dieta Vegetariana , Fatores de Risco , Idoso
18.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 30(1): 26-30, 2013 Feb.
Artigo em Zh | MEDLINE | ID: mdl-23450474

RESUMO

OBJECTIVE: To assess the influence of polymorphisms of methylenetetrahydrofolate reductase (MTHFR) gene on response to antidepressant treatment. METHODS: Two hundred and eight one Chinese Han patients have received single antidepressant drugs for at least 6 weeks, among whom 275 were followed up for 8 weeks. Hamilton depression scale 17 (HAMD-17) was used to evaluate the severity of depressive symptoms and therapeutic effects. Single nucleotide polymorphisms (SNPs) of the MTHFR gene were determined using gene chips. Associations of single loci and haplotypes with response to treatment were analyzed using an Unphased 3.0.13 software. RESULTS: No significant differences in gender, age, year of education, family history, episode times, and antidepressant agents were found between responders and non-responders (all P U+003E 0.05), while the baseline scores of HAMD-17 was significantly different(t=2.891, P=0.004). There was also no significant difference between age, years of education, family history, baseline scores of HAMD-17 and antidepressant agents between remitters and non-remitters (both P U+003E 0.05), while proportion of male patients was significantly higher in non-remission group than remission group (t=2.381, P=0.018), and episode times in non-remission group was significantly higher (t=-1.983, P=0.049). Single locus association analysis has found no significant association between SNPs rs1801131 and rs1801133 in the MTHFR gene with antidepressant response (P U+003E 0.05). On the other hand, haplotype A-C of MTHFR gene (rs1801131 and rs1801133) was significantly associated with antidepressant response in total group (U+03C7 2=11.39, P=0.0007), male subgroup (U+03C7 2=8.767, P=0.003) and serotonin noradrenaline reuptake inhibitors (SNRIs) subgroup (U+03C7 2=10.51, P=0.001). CONCLUSION: Particular haplotype of MTHFR gene may be related with antidepressant effect, in which the haplotype (rs1801131, rs1801133) A-C type may be associated with better antidepressant efficacy, particularly in males and patients receiving SNRIs drugs.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Feminino , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Fatores Sexuais , Resultado do Tratamento , Adulto Jovem
19.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 33(10): 1323-7, 2013 Oct.
Artigo em Zh | MEDLINE | ID: mdl-24432672

RESUMO

OBJECTIVE: To understand the difference in clinical indicators of gout patients of different Chinese medical syndromes and its clinical significance. METHODS: Form November 2011 to December 2012, syndrome typed were 257 male gout in-/outpatients from Affiliated Hospital of Chuanbei Medical College. Another 50 healthy male subjects were recruited as the control. Their clinical and laboratory data were collected. All were excluded from infections and other inflammatory diseases. RESULTS: Four syndrome types existed in gout patients, i.e., intermingled phlegm-stasis blood syndrome (IPSBS), obstruction of dampness and heat syndrome (ODHS), Pi-deficiency induced dampness syndrome (PDIDS), qi-blood deficiency syndrome (QBDS). Of them, 53 acute phase gout patients suffered from IPSBS, 41 from ODHS, 25 from QBDS, and 17 from PDIDS; 41 non-acute phase gout patients suffered from QBDS, 40 from PDIDS, 24 from ODHS, and 16 from IPSBS. Statistical analysis of clinical data showed that, when compared with the normal control group, there was statistical difference in blood routines (WBC, GR, LY, MO) and blood biochemical indices (UA, Ur, Cr, ALT, AST, ALB, GLOB, TG, HDL-C, VLDL-C, apoA, apoB100) of gout patients of different syndromes (P < 0.05, P < 0.01). There was also statistical difference or correlation among different syndromes (P < 0.05). CONCLUSIONS: In the acute phase gout patients, IPSBS and ODHS were dominated, while in the non-acute phase gout patients, QBDS and PDIDS were often seen. In patients of IPSBS and ODHS, inflammation and immune response were more obvious, indicating that better efficacy might be achieved by clearing heat and removing blood stasis associated anti-inflammatory and immune regulation therapies. In patients of QBDS and PDIDS, impaired renal functions were more significant, indicating that better efficacy might be achieved by invigorating Pi and tonifying Shen dominated treatment.


Assuntos
Gota/diagnóstico , Medicina Tradicional Chinesa/métodos , Adulto , Idoso , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Deficiência da Energia Yang/diagnóstico , Deficiência da Energia Yin/diagnóstico , Adulto Jovem
20.
mBio ; 14(5): e0153623, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37800901

RESUMO

IMPORTANCE: Many free-swimming bacteria propel themselves through liquid using rotary flagella, and mounting evidence suggests that the inhibition of flagellar rotation initiates biofilm formation, a sessile lifestyle that is a nearly universal surface colonization paradigm in bacteria. In general, motility and biofilm formation are inversely regulated by the intracellular second messenger bis-(3´-5´)-cyclic dimeric guanosine monophosphate (c-di-GMP). Here, we identify a protein, PlzD, bearing a conserved c-di-GMP binding PilZ domain that localizes to the flagellar pole in a c-di-GMP-dependent manner and alters the foraging behavior, biofilm, and virulence characteristics of the opportunistic human pathogen, Vibrio vulnificus. Our data suggest that PlzD interacts with components of the flagellar stator to decrease bacterial swimming speed and changes in swimming direction, and these activities are enhanced when cellular c-di-GMP levels are elevated. These results reveal a physical link between a second messenger (c-di-GMP) and an effector (PlzD) that promotes transition from a motile to a sessile state in V. vulnificus.


Assuntos
Vibrio vulnificus , Humanos , Vibrio vulnificus/fisiologia , Proteínas de Bactérias/metabolismo , Virulência , GMP Cíclico/metabolismo , Biofilmes , Regulação Bacteriana da Expressão Gênica
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