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1.
Cell ; 185(13): 2292-2308.e20, 2022 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-35750034

RESUMO

Lysosomes require an acidic lumen between pH 4.5 and 5.0 for effective digestion of macromolecules. This pH optimum is maintained by proton influx produced by the V-ATPase and efflux through an unidentified "H+ leak" pathway. Here we show that TMEM175, a genetic risk factor for Parkinson's disease (PD), mediates the lysosomal H+ leak by acting as a proton-activated, proton-selective channel on the lysosomal membrane (LyPAP). Acidification beyond the normal range potently activated LyPAP to terminate further acidification of lysosomes. An endogenous polyunsaturated fatty acid and synthetic agonists also activated TMEM175 to trigger lysosomal proton release. TMEM175 deficiency caused lysosomal over-acidification, impaired proteolytic activity, and facilitated α-synuclein aggregation in vivo. Mutational and pH normalization analyses indicated that the channel's H+ conductance is essential for normal lysosome function. Thus, modulation of LyPAP by cellular cues may dynamically tune the pH optima of endosomes and lysosomes to regulate lysosomal degradation and PD pathology.


Assuntos
Doença de Parkinson , Endossomos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Membranas Intracelulares/metabolismo , Lisossomos/metabolismo , Doença de Parkinson/metabolismo , Canais de Potássio/metabolismo , Prótons
2.
EMBO J ; 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898313

RESUMO

In cells, mRNAs are transported to and positioned at subcellular areas to locally regulate protein production. Recent studies have identified the kinesin-3 family member motor protein KIF1C as an RNA transporter. However, it is not clear how KIF1C interacts with RNA molecules. Here, we show that the KIF1C C-terminal tail domain contains an intrinsically disordered region (IDR) that drives liquid-liquid phase separation (LLPS). KIF1C forms dynamic puncta in cells that display physical properties of liquid condensates and incorporate RNA molecules in a sequence-selective manner. Endogenous KIF1C forms condensates in cellular protrusions, where mRNAs are enriched in an IDR-dependent manner. Purified KIF1C tail constructs undergo LLPS in vitro at near-endogenous nM concentrations and in the absence of crowding agents and can directly recruit RNA molecules. Overall, our work uncovers an intrinsic correlation between the LLPS activity of KIF1C and its role in mRNA positioning. In addition, the LLPS activity of KIF1C's tail represents a new mode of motor-cargo interaction that extends our current understanding of cytoskeletal motor proteins.

3.
J Neurosci ; 43(15): 2665-2681, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36898835

RESUMO

The Slack channel (KCNT1, Slo2.2) is a sodium-activated and chloride-activated potassium channel that regulates heart rate and maintains the normal excitability of the nervous system. Despite intense interest in the sodium gating mechanism, a comprehensive investigation to identify the sodium-sensitive and chloride-sensitive sites has been missing. In the present study, we identified two potential sodium-binding sites in the C-terminal domain of the rat Slack channel by conducting electrophysical recordings and systematic mutagenesis of cytosolic acidic residues in the rat Slack channel C terminus. In particular, by taking advantage of the M335A mutant, which results in the opening of the Slack channel in the absence of cytosolic sodium, we found that among the 92 screened negatively charged amino acids, E373 mutants could completely remove sodium sensitivity of the Slack channel. In contrast, several other mutants showed dramatic decreases in sodium sensitivity but did not abolish it altogether. Furthermore, molecular dynamics (MD) simulations performed at the hundreds of nanoseconds timescale revealed one or two sodium ions at the E373 position or an acidic pocket composed of several negatively charged residues. Moreover, the MD simulations predicted possible chloride interaction sites. By screening predicted positively charged residues, we identified R379 as a chloride interaction site. Thus, we conclude that the E373 site and the D863/E865 pocket are two potential sodium-sensitive sites, while R379 is a chloride interaction site in the Slack channel.SIGNIFICANCE STATEMENT The research presented here identified two distinct sodium and one chloride interaction sites located in the intracellular C-terminal domain of the Slack (Slo2.2, KCNT1) channel. Identification of the sites responsible for the sodium and chloride activation of the Slack channel sets its gating property apart from other potassium channels in the BK channel family. This finding sets the stage for future functional and pharmacological studies of this channel.


Assuntos
Canais de Potássio Ativados por Sódio , Animais , Ratos , Cloretos/metabolismo , Canais de Potássio Ativados por Sódio/metabolismo , Sódio/metabolismo
4.
Protein Expr Purif ; 210: 106315, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37271409

RESUMO

Protein A affinity chromatography has been widely used for antibody capture and initial purification. In general, the yield of this step is relatively high (i.e., >90%). However, recently while purifying a bispecific antibody (bsAb) in appended IgG format, the Protein A capture step experienced low yield (i.e., ∼80%). It was found that the target bsAb started appearing in flow-through at a relatively low load density, suggesting that a portion of the expressed bsAb has compromised Protein A binding capability. Further studies indicated that the bsAb in flow-through was mainly in aggregate form. In addition, normal Protein A step yield was restored when the column was loaded with bsAb monomer. Thus, all the evidence pointed to the fact that aggregate with compromised binding capacity was the cause of low Protein A step yield in this case.


Assuntos
Anticorpos Biespecíficos , Proteína Estafilocócica A , Anticorpos Biespecíficos/química
5.
Mol Cell Neurosci ; 122: 103759, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35901929

RESUMO

Microglia activation has been suggested as the key factor in neuro-inflammation and thus participates in neurological diseases. Although taurine exhibits anti-inflammatory and neuro-protective effects, its underlying epigenetic mechanism is unknown. In this study, taurine was administered to lipopolysaccharide (LPS)-treated mice and BV-2 cells. Behavioral test, morphological analyze, detection of microglia activation, and lysine demethylase 3a (KDM3a) measurements were performed to investigate the mechanism by which taurine regulates KDM3a and subsequently antagonizes microglia activation. Taurine improved the sociability of LPS-treated mice, inhibited microglia activation in the hippocampus, and reduced generation of brain inflammatory factors, such as interleukin-6, tumor necrosis factor-α, inducible nitric oxide synthase, and cyclooxygenase-2. Meanwhile, taurine suppressed the LPS-induced increase in microglial KDM3a, and increased the level of mono-, di- or tri-methylation of lysine 9 on histone H3 (H3K9me1/2/3). Furthermore, taurine inhibited the LPS-induced increase in KDM3a, elevated the H3K9me1/2/3 level, and reduced inflammatory factors and reactive oxygen species in a concentration-dependent manner in LPS-stimulated BV-2 cells. In conclusion, taurine inhibited KDM3a and microglia activation, thereby playing an anti-inflammatory role in LPS-treated mice and BV-2 cells.


Assuntos
Lipopolissacarídeos , Microglia , Animais , Anti-Inflamatórios/farmacologia , Linhagem Celular , Ciclo-Oxigenase 2/metabolismo , Ciclo-Oxigenase 2/farmacologia , Lipopolissacarídeos/toxicidade , Lisina , Camundongos , Microglia/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Taurina/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
6.
Acta Biochim Biophys Sin (Shanghai) ; 55(9): 1358-1369, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587757

RESUMO

Mounting evidence demonstrates that hydrogen sulfide (H 2S) promotes anti-inflammatory molecules and inhibits pro-inflammatory cytokines in endothelial cells (ECs). This study aims to investigate the favorable action of H 2S on endothelial function in senescence by inhibiting the production of inflammatory molecules. Senescent ECs exhibit a reduction in H 2S, endothelial nitric oxide synthase (eNOS) and peroxisome proliferator-activated receptor δ (PPARδ), coupled with increased inflammatory molecules, sodium glucose transporter type 2 (SGLT2) and phosphorylation of STAT3, which could be reversed by the administration of a slow but sustained release agent of H 2S, GYY4137. Decreased production of eNOS and upregulated p-STAT3 and SGLT2 levels in senescent ECs are reversed by replenishment of the SGLT2 inhibitor EMPA and the PPARδ agonist GW501516. The PPARδ antagonist GSK0660 attenuates eNOS expression and increases the production of p-STAT3 and SGLT2. However, supplementation with GYY4137 has no beneficial effect on GSK0660-treated ECs. GYY4137, GW501516 and EMPA preserve endothelial-dependent relaxation (EDR) in D-gal-treated aortae, while GSK0660 destroys aortic relaxation even with GYY4137 supplementation. In summary, senescent ECs manifest aggravated the expressions of the inflammatory molecules SGLT2 and p-STAT3 and decreased the productions of PPARδ, eNOS and CSE. H 2S ameliorates endothelial dysfunction through the anti-inflammatory effect of the PPARδ/SGLT2/p-STAT3 signaling pathway in senescent ECs and may be a potential therapeutic target for anti-ageing treatment.


Assuntos
Sulfeto de Hidrogênio , PPAR delta , Humanos , Células Endoteliais , Sulfeto de Hidrogênio/farmacologia , Transportador 2 de Glucose-Sódio , Inflamação/tratamento farmacológico , Fator de Transcrição STAT3
7.
BMC Biol ; 20(1): 121, 2022 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-35606800

RESUMO

BACKGROUND: Men with prediabetes often exhibit concomitant low-quality sperm production or even infertility, problems which urgently require improved therapeutic options. In this study, we have established a sheep model of diet-induced prediabetes that is associated with spermatogenic defects and have explored the possible underlying metabolic causes. RESULTS: We compared male sheep fed a normal diet with those in which prediabetes was induced by a rich diet and with a third group in which the rich diet was supplemented by melatonin. Only the rich diet group had symptoms of prediabetes, and in these sheep, we found impaired spermatogenesis characterized by a block in the development of round spermatids and an increased quantity of testicular apoptotic cells. Comparing the gut microbiomes and intestinal digest metabolomes of the three groups revealed a distinctive difference in the taxonomic composition of the microbiota in prediabetic sheep, and an altered metabolome, whose most significant feature was altered sphingosine metabolism; elevated sphingosine was also found in blood and testes. Administration of melatonin alleviated the symptoms of prediabetes, including those of impaired spermatogenesis, while restoring a more normal microbiota and metabolic levels of sphingosine. Fecal microbiota transplantation from prediabetic sheep induced elevated sphingosine levels and impaired spermatogenesis in recipient mice, indicating a causal role of gut microbiota in these phenotypes. CONCLUSIONS: Our results point to a key role of sphingosine in the disruption of spermatogenesis in prediabetic sheep and suggest it could be a useful disease marker; furthermore, melatonin represents a potential prebiotic agent for the treatment of male infertility caused by prediabetes.


Assuntos
Microbioma Gastrointestinal , Melatonina , Estado Pré-Diabético , Animais , Apoptose , Humanos , Masculino , Camundongos , Estado Pré-Diabético/complicações , Ovinos , Esfingosina , Testículo
8.
BMC Biol ; 20(1): 125, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35637443

RESUMO

BACKGROUND: During the disease cycle, plant pathogenic fungi exhibit a morphological transition between hyphal growth (the phase of active infection) and the production of long-term survival structures that remain dormant during "overwintering." Verticillium dahliae is a major plant pathogen that produces heavily melanized microsclerotia (MS) that survive in the soil for 14 or more years. These MS are multicellular structures produced during the necrotrophic phase of the disease cycle. Polyketide synthases (PKSs) are responsible for catalyzing production of many secondary metabolites including melanin. While MS contribute to long-term survival, hyphal growth is key for infection and virulence, but the signaling mechanisms by which the pathogen maintains hyphal growth are unclear. RESULTS: We analyzed the VdPKSs that contain at least one conserved domain potentially involved in secondary metabolism (SM), and screened the effect of VdPKS deletions in the virulent strain AT13. Among the five VdPKSs whose deletion affected virulence on cotton, we found that VdPKS9 acted epistatically to the VdPKS1-associated melanin pathway to promote hyphal growth. The decreased hyphal growth in VdPKS9 mutants was accompanied by the up-regulation of melanin biosynthesis and MS formation. Overexpression of VdPKS9 transformed melanized hyphal-type (MH-type) into the albinistic hyaline hyphal-type (AH-type), and VdPKS9 was upregulated in the AH-type population, which also exhibited higher virulence than the MH-type. CONCLUSIONS: We show that VdPKS9 is a powerful negative regulator of both melanin biosynthesis and MS formation in V. dahliae. These findings provide insight into the mechanism of how plant pathogens promote their virulence by the maintenance of vegetative hyphal growth during infection and colonization of plant hosts, and may provide novel targets for the control of melanin-producing filamentous fungi.


Assuntos
Policetídeo Sintases , Verticillium , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Melaninas/metabolismo , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Metabolismo Secundário , Verticillium/metabolismo , Virulência
9.
Gut ; 71(1): 78-87, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33504491

RESUMO

OBJECTIVE: Effects of the diet-induced gut microbiota dysbiosis reach far beyond the gut. We aim to uncover the direct evidence involving the gut-testis axis in the aetiology of impaired spermatogenesis. DESIGN: An excessive-energy diet-induced metabolic syndrome (MetS) sheep model was established. The testicular samples, host metabolomes and gut microbiome were analysed. Faecal microbiota transplantation (FMT) confirmed the linkage between gut microbiota and spermatogenesis. RESULTS: We demonstrated that the number of arrested spermatogonia was markedly elevated by using 10× single-cell RNA-seq in the MetS model. Furthermore, through using metabolomics profiling and 16S rDNA-seq, we discovered that the absorption of vitamin A in the gut was abolished due to a notable reduction of bile acid levels, which was significantly associated with reduced abundance of Ruminococcaceae_NK4A214_group. Notably, the abnormal metabolic effects of vitamin A were transferable to the testicular cells through the circulating blood, which contributed to abnormal spermatogenesis, as confirmed by FMT. CONCLUSION: These findings define a starting point for linking the testicular function and regulation of gut microbiota via host metabolomes and will be of potential value for the treatment of male infertility in MetS.


Assuntos
Microbioma Gastrointestinal/fisiologia , Síndrome Metabólica/fisiopatologia , Espermatogênese/fisiologia , Testículo/fisiologia , Vitamina A/metabolismo , Animais , Ácidos e Sais Biliares/metabolismo , Modelos Animais de Doenças , Disbiose/fisiopatologia , Masculino , Metaboloma , Ovinos
10.
J Transl Med ; 20(1): 67, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115019

RESUMO

BACKGROUND: Chinese herbal medicine is made up of hundreds of natural drug molecules and has played a major role in traditional Chinese medicine (TCM) for several thousand years. Therefore, it is of great significance to study the target of natural drug molecules for exploring the mechanism of treating diseases with TCM. However, it is very difficult to determine the targets of a fresh natural drug molecule due to the complexity of the interaction between drug molecules and targets. Compared with traditional biological experiments, the computational method has the advantages of less time and low cost for targets screening, but it remains many great challenges, especially for the molecules without social ties. METHODS: This study proposed a novel method based on the Cosine-correlation and Similarity-comparison of Local Network (CSLN) to perform the preliminary screening of targets for the fresh natural drug molecules and assign weights to them through a trained parameter. RESULTS: The performance of CSLN is superior to the popular drug-target-interaction (DTI) prediction model GRGMF on the gold standard data in the condition that is drug molecules are the objects for training and testing. Moreover, CSLN showed excellent ability in checking the targets screening performance for a fresh-natural-drug-molecule (scenario simulation) on the TCMSP (13 positive samples in top20), meanwhile, Western-Blot also further verified the accuracy of CSLN. CONCLUSIONS: In summary, the results suggest that CSLN can be used as an alternative strategy for screening targets of fresh natural drug molecules.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/uso terapêutico , Medicina Tradicional Chinesa/métodos
11.
Diabetologia ; 64(1): 226-239, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33106900

RESUMO

AIMS/HYPOTHESIS: Microvascular endothelial hyperpermeability, mainly caused by claudin-5 deficiency, is the initial pathological change that occurs in diabetes-associated cardiovascular disease. The ketone body ß-hydroxybutyrate (BHB) exerts unique beneficial effects on the cardiovascular system, but the involvement of BHB in promoting the generation of claudin-5 to attenuate cardiac microvascular hyperpermeability in diabetes is poorly understood. METHODS: The effects of BHB on cardiac microvascular endothelial hyperpermeability and claudin-5 generation were evaluated in rats with streptozotocin-induced diabetes and in high glucose (HG)-stimulated human cardiac microvascular endothelial cells (HCMECs). To explore the underlying mechanisms, we also measured ß-catenin nuclear translocation, binding of ß-catenin, histone deacetylase (HDAC)1, HDAC3 and p300 to the Claudin-5 (also known as CLDN5) promoter, interaction between HDAC3 and ß-catenin, and histone acetylation in the Claudin-5 promoter. RESULTS: We found that 10 weeks of BHB treatment promoted claudin-5 generation and antagonised cardiac microvascular endothelial hyperpermeability in rat models of diabetes. Meanwhile, BHB promoted claudin-5 generation and inhibited paracellular permeability in HG-stimulated HCMECs. Specifically, BHB (2 mmol/l) inhibited HG-induced HDAC3 from binding to the Claudin-5 promoter, although nuclear translocation or promoter binding of ß-catenin did not change with BHB treatment. In addition, BHB prevented the binding and co-localisation of HDAC3 to ß-catenin in HG-stimulated HCMECs. Furthermore, using mass spectrometry, acetylated H3K14 (H3K14ac) in the Claudin-5 promoter following BHB treatment was identified, regardless of whether cells were stimulated by HG or not. Although reduced levels of acetylated H3K9 in the Claudin-5 promoter were found following HG stimulation, increased H3K14ac was specifically associated with BHB treatment. CONCLUSIONS/INTERPRETATION: BHB inhibited HDAC3 and caused acetylation of H3K14 in the Claudin-5 promoter, thereby promoting claudin-5 generation and antagonising diabetes-associated cardiac microvascular hyperpermeability. Graphical abstract.


Assuntos
Ácido 3-Hidroxibutírico/farmacologia , Permeabilidade Capilar/efeitos dos fármacos , Claudina-5/biossíntese , Vasos Coronários/fisiopatologia , Diabetes Mellitus Experimental/fisiopatologia , Histona Desacetilases/efeitos dos fármacos , Animais , Permeabilidade Capilar/fisiologia , Claudina-5/genética , Complicações do Diabetes/prevenção & controle , Endotélio Vascular/fisiopatologia , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Masculino , Microvasos/fisiopatologia , Regiões Promotoras Genéticas/fisiologia , Ratos , Ratos Sprague-Dawley , beta Catenina/metabolismo
12.
Zhongguo Zhong Yao Za Zhi ; 46(18): 4816-4823, 2021 Sep.
Artigo em Zh | MEDLINE | ID: mdl-34581093

RESUMO

The present study explored the mechanism of Fagopyri Dibotryis Rhizoma(FDR) and its main active components in the treatment of acute lung injury(ALI) based on the network pharmacology and the in vitro experiments. The main active components of FDR were obtained from the TCMSP database and screened by oral bioavailability and drug-likeness. The related target proteins of FDR were retrieved from the PubChem database, and the target genes related to ALI were screened out from the GeneCards database. A protein-protein interaction(PPI) network of compound target proteins and ALI target genes was constructed using STRING 11.0. Ingenuity Pathway Analysis(IPA) platform was used to analyze the common pathways of the potential compound target proteins of FDR and ALI target genes, thereby predicting the key targets and potential signaling pathways of FDR for the treatment of ALI. Finally, the potential pathways and key targets were verified by the in vitro experiments of lipopolysaccharide-induced RAW264.7 cells intervened by epicatechin(EC), the active component of FDR. The results of network pharmacology showed that 15 potential active components such as EC, procyanidin B1, and luteolin presumedly functioned in the treatment of ALI through nuclear transcription factor-κB(NF-κB) signaling pathway, transforming growth factor-ß(TGF-ß) signaling pathway, and adenosine 5'-monophosphate(AMP)-activated protein kinase(AMPK) signaling pathway through key targets, such as RELA(P65). The results of in vitro experiments showed that 25 µmol·L~(-1) EC had no toxicity to cells and could inhibit the expression of the p65-phosphorylated protein in the NF-κB signaling pathway to down-regulate the expression of downstream inflammatory cytokines, including tumor necrosis factor-α(TNF-α), IL-1ß and nitric oxide(NO), and up-regulate the expression of IL-10. These results suggested that the therapeutic efficacy of FDR on ALI was achieved by inhibiting the phosphorylation of p65 protein in the NF-κB signaling pathway and down-regulating the level of proinflammatory cytokines downstream of the signaling pathways.


Assuntos
Lesão Pulmonar Aguda , Lesão Pulmonar Aguda/tratamento farmacológico , Lesão Pulmonar Aguda/genética , Lipopolissacarídeos , NF-kappa B/genética , NF-kappa B/metabolismo , Rizoma , Transdução de Sinais
13.
J Virol ; 92(13)2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29669833

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) has represented a human health threat since 2012. Although several MERS-related CoVs that belong to the same species as MERS-CoV have been identified from bats, they do not use the MERS-CoV receptor, dipeptidyl peptidase 4 (DPP4). Here, we screened 1,059 bat samples from at least 30 bat species collected in different regions in south China and identified 89 strains of lineage C betacoronaviruses, including Tylonycteris pachypus coronavirus HKU4, Pipistrellus pipistrelluscoronavirus HKU5, and MERS-related CoVs. We sequenced the full-length genomes of two positive samples collected from the great evening bat, Ia io, from Guangdong Province. The two genomes were highly similar and exhibited genomic structures identical to those of other lineage C betacoronaviruses. While they exhibited genome-wide nucleotide identities of only 75.3 to 81.2% with other MERS-related CoVs, their gene-coding regions were highly similar to their counterparts, except in the case of the spike proteins. Further protein-protein interaction assays demonstrated that the spike proteins of these MERS-related CoVs bind to the receptor DPP4. Recombination analysis suggested that the newly discovered MERS-related CoVs have acquired their spike genes from a DPP4-recognizing bat coronavirus HKU4. Our study provides further evidence that bats represent the evolutionary origins of MERS-CoV.IMPORTANCE Previous studies suggested that MERS-CoV originated in bats. However, its evolutionary path from bats to humans remains unclear. In this study, we discovered 89 novel lineage C betacoronaviruses in eight bat species. We provide evidence of a MERS-related CoV derived from the great evening bat that uses the same host receptor as human MERS-CoV. This virus also provides evidence for a natural recombination event between the bat MERS-related CoV and another bat coronavirus, HKU4. Our study expands the host ranges of MERS-related CoV and represents an important step toward establishing bats as the natural reservoir of MERS-CoV. These findings may lead to improved epidemiological surveillance of MERS-CoV and the prevention and control of the spread of MERS-CoV to humans.


Assuntos
Quirópteros/virologia , Infecções por Coronavirus/veterinária , Evolução Molecular , Genoma Viral , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Receptores Virais/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Animais , Quirópteros/genética , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Especificidade de Hospedeiro , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/classificação , Filogenia , Receptores Virais/genética , Homologia de Sequência , Proteínas Virais/genética
14.
BMC Genomics ; 19(1): 742, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30305015

RESUMO

BACKGROUND: Gray leaf spot (GLS), which is caused by the necrotrophic fungi Cercospora zeae-maydis and Cercospora zeina, is one of the most impactful diseases in maize worldwide. The aim of the present study is to identify the resistance genes and understand the molecular mechanisms for GLS resistance. RESULTS: Two cultivars, 'Yayu889' and 'Zhenghong532,' which are distinguished as resistant and susceptible cultivars, respectively, were challenged with the GLS disease and a RNA-seq experiment was conducted on infected plants at 81, 89, 91, and 93 days post planting (dap). Compared with the beginning stage at 81 dap, 4666, 1733, and 1166 differentially expressed genes (DEGs) were identified at 89, 91, and 93 dap, respectively, in 'Yayu889,' while relatively fewer, i.e., 4713, 881, and 722 DEGs, were identified in 'Zhenghong532.' Multiple pathways involved in the response of maize to GLS, including 'response to salicylic acid,' 'protein phosphorylation,' 'oxidation-reduction process,' and 'carotenoid biosynthetic process,' were enriched by combining differential expression analysis and Weighted Gene Co-expression Network Analysis (WGCNA). The expression of 12 candidate resistance proteins in these pathways were quantified by the multiple reaction monitoring (MRM) method. This approach identified two candidate resistance proteins, a calmodulin-like protein and a leucine-rich repeat receptor-like protein kinase with SNPs that were located in QTL regions for GLS resistance. Metabolic analysis showed that, compared with 'Zhenghong532,' the amount of salicylic acid (SA) and total carotenoids in 'Yayu889' increased, while peroxidase activity decreased during the early infection stages, suggesting that increased levels of SA, carotenoids, and reactive oxygen species (ROS) may enhance the defense response of 'Yayu889' to GLS. CONCLUSION: By combining transcriptome and proteome analyses with comparisons of resistance QTL regions, calmodulin-like protein and leucine-rich repeat receptor-like protein kinase were identified as candidate GLS resistance proteins. Moreover, we found that the metabolic pathways for ROS, SA, and carotenoids are especially active in the resistant cultivar. These findings could lead to a better understanding of the GLS resistance mechanisms and facilitate the breeding of GLS-resistant maize cultivars.


Assuntos
Resistência à Doença/genética , Perfilação da Expressão Gênica , Doenças das Plantas/microbiologia , Zea mays/genética , Zea mays/microbiologia , Ascomicetos/fisiologia , Carotenoides/metabolismo , Ontologia Genética , Peroxidases/metabolismo , Ácido Salicílico/metabolismo , Zea mays/imunologia , Zea mays/metabolismo
15.
Cell Physiol Biochem ; 46(4): 1525-1535, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29689546

RESUMO

BACKGROUND/AIMS: The metabolic features of cancer cells have long been acknowledged to be altered and to provide new therapeutic opportunities. The expression of glycolytic enzyme enolase 2 (ENO2) was found to be closely associated with the clinical features of acute lymphoblastic leukemia (ALL) patients, but its functions remain unclear in ALL. METHODS: We evaluated the association between ENO2 mRNA expression in bone marrow mononuclear cells (BM-MNCs) and the efficacy of chemotherapy, and further explored the function of ENO2 in ALL. The molecular mechanisms of ENO2 expression and its effects on cell growth, glycolysis and glucocorticoid resistance were explored by Cell Counting Kit-8, glucose-consumption assay, Quantitative RT-PCR, Western blotting and in vivo tumorigenesis in NOD/SCID mice. RESULTS: The results showed that ENO2 mRNA expression in BM-MNCs was significantly decreased when patients completed induction chemotherapy and reached complete remission (CR). ENO2 mRNA expression was increased when patients suffered relapse. Functional studies demonstrated that ENO2 promoted cell growth, glycolysis, and glucocorticoid resistance, all of which were effectively inhibited when ENO2 was silenced with shRNAs. Further studies revealed that ENO2 up-regulated various glycolysis-related genes and enhanced Akt activity with subsequent glycogen synthase kinase3ß (GSK-3ß) phosphorylation, inducing cell proliferation and glycolysis. The combination of silencing ENO2 and 2-deoxyglucose (2-DG) synergistically inhibited leukemia cell survival. CONCLUSIONS: These results indicate that ENO2 may be a biological marker for monitoring chemotherapeutic efficacy and relapse in ALL. ENO2 may provide a potential therapeutic strategy for ALL.


Assuntos
Fosfopiruvato Hidratase/metabolismo , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desoxiglucose/farmacologia , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Glicólise/efeitos dos fármacos , Células HEK293 , Humanos , Células Jurkat , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Fosfopiruvato Hidratase/antagonistas & inibidores , Fosfopiruvato Hidratase/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transplante Heterólogo
16.
Ann Hematol ; 96(12): 2079-2088, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28871325

RESUMO

The IL-2/IL-2 receptor (IL-2R) system plays a central role in maintaining normal T cell immunity, and its disturbance is associated with several hematologic disorders. Studies have found in several types of lymphoma that abnormal amounts of soluble IL-2R (sIL-2R) may result in imbalance of the IL-2/IL-2R system and hence of the T cell immunoregulation. Whether the level of sIL-2R in blood could predict treatment outcomes or not needs to be investigated in multiple myeloma (MM) patients. The level of sIL-2R in serum was measured using enzyme-linked immunosorbent assay (ELISA) in 81 patients with newly diagnosed MM. Twenty-six patients (32.1%) were treated with bortezomib-based regimens and 55patients (67.9%) received old drugs-based regimens. The mean concentration of sIL-2R for myeloma patients was 8.51 ng/ml, significantly higher than that of healthy controls (0.56 ng/ml, p < 0.0001). The best cutoff value for sIL-2R in predicting high risk for disease progression is 6.049 ng/ml with an area under curve (AUC) of 0.665 (p = 0.013). Thirty-six patients (44.4%) were classified as higher sIL-2R level group (> 6.049 ng/ml), and 45 patients (55.6%) as lower group (≤ 6.049 ng/ml). The overall response rate (ORR) was 60.0% in lower sIL-2R level group, and 41.7% in higher level group (p = 0.156). The median progression-free survival (PFS) and overall survival (OS) was 12 months (range, 2.0-65 months) and 20 months (range, 2.0-118 months), respectively. In a multivariate survival analysis, including Eastern Cooperative Oncology Group performance status score, treatment response, and sIL-2R level, it was found that all these three parameters were significantly independent prognostic factors for PFS (p = 0.032, 0.016, and 0.043, respectively), but none factors maintained their value in predicting OS. Subgroup analysis revealed that high level of sIL-2R is correlated with significantly inferior PFS in patients treated with bortezomib-based regimens (p = 0.004). Serum sIL-2R level is an independent prognostic factor for PFS, indicating novel drugs targeting the imbalance of IL-2/IL-2R system may be a promising strategy in MM.


Assuntos
Bortezomib/administração & dosagem , Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo , Proteínas de Neoplasias/sangue , Receptores de Interleucina-2/sangue , Idoso , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Fatores de Risco , Taxa de Sobrevida
17.
Br J Cancer ; 114(4): 463-8, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26882069

RESUMO

BACKGROUND: Interleukin-10 (IL-10) is a inhibiting inflammatory cytokine that plays an important role in immune suppressive microenvironment in multiple myeloma (MM). Whether the level of serum IL-10 could predict treatment response and survival outcomes or not needs to be investigated in MM patients. METHODS: The level of IL-10 in serum was measured using enzyme-linked immunosorbent assay in 188 patients with newly diagnosed MM. RESULTS: The best cutoff value for IL-10 in predicting survival is 169.69 pg ml(-1) with an area under the curve (AUC) value of 0.747 (P<0.001). In all, 92 patients (48.9%) were classified as high-IL-10 group (>169.96 pg ml(-1)) and 96 patients (51.1%) as low-IL-10 group (⩽169.96 pg ml(-1)). The overall response rate (ORR) was 79.2% in low-IL-10 group, significantly higher than that in high-IL-10 group (53.3%, P<0.001). Patients in low-IL-10 group had significantly better survival compared with those in high-IL-10 group (3-year PFS rate: 69.3% vs 13.3%, P<0.001; 3-year OS rate: 93.6% vs 51.9%, P<0.001). Multivariate analysis revealed that serum IL-10 level >169.96 pg ml(-1) at diagnosis and certain cytogenetic abnormalities were two adverse factors for PFS and OS. CONCLUSIONS: Our data suggest that serum IL-10 at diagnosis is a novel, powerful predictor of prognosis for MM.


Assuntos
Biomarcadores Tumorais/sangue , Interleucina-10/sangue , Mieloma Múltiplo/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
18.
Can J Microbiol ; 62(11): 970-979, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27696894

RESUMO

Tuber pseudoexcavatum, Tuber sinoaestivum, and Tuber indicum are the 3 most important truffles growing in southeast China; however, their cultivation is still inefficient owing to the lack of understanding regarding the composition and function of the bacterial and fungal communities from the soils around the fruit bodies and the ectomycorrhiza of these truffles. The aim of this study was to disclose the microbial communities in truffle-producing soils in Huidong County, Sichuan, China, by using barcoded pyrosequencing. Approximately 350 000 quality-controlled sequences were obtained and grouped into 14 025 bacterial operational taxonomic units (OTUs) and 4385 fungal OTUs, which included 29 bacterial and 7 fungal phyla, respectively. The bacterial genus Acidobacterium and fungal genera Modicella, Pseudogymnoascus, and Mortierella were significantly more abundant in the control soils than in the truffle-producing soils (P < 0.05), while the bacterial genus Sphingomonas (Alphaproteobacteria) and arbuscular mycorrhizal fungal genus Glomus were significantly enriched in truffle-producing soil than in the control (P < 0.05), indicating their different roles within truffle grounds. Notably, some nonfungal organisms detected by 18S rDNA pyrosequencing were of high abundance, among which Cercozoa and Ochrophyta were significantly (P < 0.05) more abundant in truffle soils than in control soils, indicating their interactions with truffles.

19.
Appl Opt ; 55(20): 5358-61, 2016 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-27409311

RESUMO

We have theoretically investigated a hybrid system that is composed of a traditional optomechanical component and an additional charge qubit (Cooper pair box) that induces a new nonlinear interaction. It is shown that the peak in optomechanically induced transparency has been split by the new nonlinear interaction, and the width of the splitting is proportional to the coupling coefficient of this nonlinear interaction. This may give a way to measure the nanomechanical oscillator-qubit coupling coefficient in hybrid quantum systems.

20.
Ann Hematol ; 94(8): 1389-400, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25869028

RESUMO

The prognostic nutritional index (PNI), an indicator of nutritional status and systemic inflammation, is associated with survival in several types of tumors. The prognostic value of the PNI in lymphoma remains unclear. The present study aimed to evaluate the prognostic significance of the PNI in patients with extranodal natural killer/T cell lymphoma, nasal type (ENKTL). This retrospective study in two institutions was comprised of 177 patients with newly diagnosed ENKTL. Patients with a combined albumin (g/L) + 5 × total lymphocyte count × 10(9)/l ≥ 45 were allocated a PNI score of 0. Patients in whom this total was <45 were allocated a score of 1. Patients with a pretreatment PNI score of 1 had more adverse clinical features, lower complete remission rates (p = 0.005), and worse overall survival (OS, p < 0.001) and progression-free survival (p = 0.004) compared with those with a PNI score of 0. Multivariate analysis showed that the PNI (p < 0.001) and tumor mass ≥5 cm (p < 0.001) were independent predictors of worse OS. The PNI was predictive in extranasal disease and nasal disease (both p < 0.05). The PNI could differentiate low-risk patients as classified according to the International Prognostic Index and Prognosis Index for peripheral T cell lymphoma scoring, as well as patients in a different category using the Korean Prognostic Index scores with different survival outcomes (all p < 0.05). The PNI is a powerful predictor of survival in ENKTL. Nutritional status and inflammatory responses at diagnosis might play an important role in survival in patients with ENKTL.


Assuntos
Linfoma Extranodal de Células T-NK/diagnóstico , Linfoma Extranodal de Células T-NK/terapia , Neoplasias Nasais/diagnóstico , Neoplasias Nasais/terapia , Avaliação Nutricional , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Criança , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Adulto Jovem
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