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1.
Anal Chem ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39018067

RESUMO

Efficient carrier separation is vitally crucial to improving the detection sensitivity of photoelectrochemical (PEC) biosensors. Here, we developed a facile strategy to efficiently regulate the carrier separation efficiency of the photoactive matrix BiOI and In2S3 signal label functionalized paper chip by manipulation of electrons spin-state and rational design of electron transport pathways. The spin-dependent electronic structures of BiOI and In2S3 were regulated via enhanced electron-spin parallel alignment induced by an external magnetic field, markedly retarding carrier recombination and extending their lifetime. Simultaneously, with the progress of the target-induced catalytic hairpin assembly process, the transfer path of photogenerated carriers was changed, leading to a switch in photocurrent polarity from cathode to anode. This reversed electron transport pathway not only boosted the separation ability of photogenerated electrons but also eliminated false-positive and false-negative signals, thereby further improving the detection sensitivity. As a proof of concept, the well-designed magnetic field-stimulated paper-based PEC biosensor showed highly selectivity and sensitivity for acetamiprid assay with a wide linear range of 1 fM to 20 nM and an ultralow detection limit of 0.73 fM. This work develops a universal strategy for improving the sensitivity of biosensors and exhibits enormous potential in the fields of bioanalysis and clinical diagnosis.

2.
J Med Virol ; 96(2): e29473, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38362929

RESUMO

Human papillomaviruses (HPVs) cause more than 4.5% of all cancer in the world and more than half of these cases are attributed to human papillomavirus type 16 (HPV16). Prophylactic vaccines are available but antiviral drugs are not. Novel targets for therapy are urgently needed. Alternative RNA splicing is extensively used by HPVs to express all their genes and HPV16 is no exception. This process must function to perfection since mis-splicing could perturb the HPV gene expression program by altering mRNA levels or by generating dysfunctional mRNAs. Cis-acting RNA elements on the viral mRNAs and their cognate cellular trans-acting factors control papillomavirus RNA splicing. The precise but delicate nature of the splicing process renders splicing sensitive to interference. As such, papillomavirus RNA splicing is a potential target for therapy. Here we summarize our current understanding of cis-acting HPV16 RNA elements that control HPV16 mRNA splicing via cellular proteins and discuss how they may be exploited as targets for therapy to papillomavirus infections and cancer.


Assuntos
Neoplasias , Proteínas Oncogênicas Virais , Infecções por Papillomavirus , Humanos , Proteínas Oncogênicas Virais/genética , Splicing de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Viral/genética , RNA Viral/metabolismo , Papillomavirus Humano , Infecções por Papillomavirus/tratamento farmacológico
3.
Bioorg Chem ; 147: 107374, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636433

RESUMO

The incidence of idiopathic pulmonary fibrosis (IPF) has been steadily increasing each year, posing significant challenges in its treatment. In this study, we conducted the design and synthesis of 23 new inhibitors that specifically target the TGF-ß1/Smad3 pathway. Initially, we employed a cell model of TGF-ß-induced pulmonary fibrosis, using cell survival rate and HYP expression as indicators to identify the potent ingredient 5aa, which demonstrated significant anti-pulmonary fibrosis activity. Subsequently, we induced mice with bleomycin (BLM) to establish an experimental animal model of pulmonary fibrosis, and evaluated the pharmacodynamics of 5aa in vivo against pulmonary fibrosis. The alterations in HYP and collagen levels in BLM-induced pulmonary fibrosis mice were analyzed using ELISA and immunohistochemistry techniques. The results indicated that compound 5aa effectively suppressed the fibrotic response induced by TGF-ß1, inhibited the expression of the fibrotic marker α-SMA, and hindered the EMT process in NIH3T3 cells. Additionally, oral administration of 5aa demonstrated significant therapeutic effects in a mouse model of IPF, comparable to the established drug Nintedanib. Moreover, compound 5aa exhibited higher bioavailability in vivo compared to Nintedanib. These collective outcomes suggest that 5aa holds promise as a potential inhibitor of TGF-ß1/Smad3 signaling for the treatment of IPF.


Assuntos
Fibrose Pulmonar Idiopática , Transdução de Sinais , Proteína Smad3 , Fator de Crescimento Transformador beta1 , Animais , Proteína Smad3/metabolismo , Proteína Smad3/antagonistas & inibidores , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Camundongos , Transdução de Sinais/efeitos dos fármacos , Estrutura Molecular , Humanos , Bleomicina , Relação Estrutura-Atividade , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Relação Dose-Resposta a Droga , Masculino
4.
Nucleic Acids Res ; 50(7): 3867-3891, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35357488

RESUMO

Human papillomavirus type 16 (HPV16) E2 is an essential HPV16 protein. We have investigated how HPV16 E2 expression is regulated and have identifed a splicing enhancer that is required for production of HPV16 E2 mRNAs. This uridine-less splicing enhancer sequence (ACGAGGACGAGGACAAGGA) contains 84% adenosine and guanosine and 16% cytosine and consists of three 'AC(A/G)AGG'-repeats. Mutational inactivation of the splicing enhancer reduced splicing to E2-mRNA specific splice site SA2709 and resulted in increased levels of unspliced E1-encoding mRNAs. The splicing enhancer sequence interacted with cellular RNA binding protein hnRNP G that promoted splicing to SA2709 and enhanced E2 mRNA production. The splicing-enhancing function of hnRNP G mapped to amino acids 236-286 of hnRNP G that were also shown to interact with splicing factor U2AF65. The interactions between hnRNP G and HPV16 E2 mRNAs and U2AF65 increased in response to keratinocyte differentiation as well as by the induction of the DNA damage response (DDR). The DDR reduced sumoylation of hnRNP G and pharmacological inhibition of sumoylation enhanced HPV16 E2 mRNA splicing and interactions between hnRNP G and E2 mRNAs and U2AF65. Intriguingly, hnRNP G also promoted intron retention of the HPV16 E6 coding region thereby inhibiting production of spliced E7 oncogene mRNAs.


Assuntos
Proteínas de Ligação a DNA/genética , Ribonucleoproteínas Nucleares Heterogêneas , Papillomavirus Humano 16 , Proteínas Oncogênicas Virais/genética , Proteínas E7 de Papillomavirus/genética , Proteínas de Ligação a DNA/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Papillomavirus Humano 16/genética , Humanos , Proteínas Oncogênicas Virais/metabolismo , Oncogenes , Splicing de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
5.
Molecules ; 29(16)2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39202958

RESUMO

Over the past decade, the production of biofuels from lignocellulosic biomass has steadily increased to offset the use of fuels from petroleum. To make biofuels cost-competitive, however, it is necessary to add value to the "ligno-" components (up to 30% by mass) of the biomass. The properties of lignin, in terms of molecular weight (MW), chemical functionality, and mineral impurities often vary from biomass source and biorefinery process, resulting in a challenging precursor for product development. Activated carbon (AC) is a feasible target for the lignin-rich byproduct streams because it can be made from nearly any biomass, and it has a market capacity large enough to use much of the lignin generated from the biorefineries. However, it is not known how the variability in the lignin affects the key properties of AC, because, until now, they could not be well controlled. In this work, various fractions of ultraclean (<0.6% ash) lignin are created with refined MW distributions using Aqueous Lignin Purification using Hot Agents (ALPHA) and used as precursors for AC. AC is synthesized via zinc chloride activation and characterized for pore structure and adsorption capacity. We show that AC surface area and the adsorption capacity increase when using lignin with increasing MW, and, furthermore, that reducing the mineral content of lignin can significantly enhance the AC properties. The surface area of the AC from the highest MW lignin can reach ~1830 m2/g (absorption capacity). Furthermore, single step activation carbonization using zinc chloride allows for minimal carbon burn off (<30%), capturing most of the lignin carbon compared to traditional burn off methods in biorefineries for heat generation.

6.
J Org Chem ; 88(21): 15478-15485, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37824753

RESUMO

Acetic acid-catalyzed (3 + 2) cyclization reaction of substituted 2-aroyl-3-aryl-1,1-dicyanocyclopropanes with arylhydrazines was investigated for the efficient synthesis of 4-dicyanomethyl-1,3,5-triaryl-4,5-dihydropyrazoles in good yields, in which 4,5-double substituents are predominantly trans selective. This approach included the consecutive condensation, ring opening, and double nucleophilic cyclization reaction.

7.
Bioorg Chem ; 131: 106317, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36525920

RESUMO

Radioresistance represents a common phenomenon found in cancer treatment. Herein, the current study sought to evaluate the effects of a nanodrug delivery system of YSAYPDSVPMMS (YSA) peptide-modified gold nanoparticles-dextran-based hydrogel loaded with paclitaxel-succinic anhydride (P-Y/G@NHs) on non-small cell lung cancer (NSCLC) cell radiosensitivity. Firstly, utilizing the coupling reaction and layer-by-layer assembly technique, P-Y/G@NHs was prepared. The therapeutic effects of the P-Y/G@NHs in NSCLC cells in relation to the PI3K/AKT signaling pathway were examined by assessing the colony formation, apoptosis, and reactive oxygen species (ROS) generation of A549 cells under 10 Gy X-rays irradiation. Moreover, A549 tumor-bearing mice were generated to further validate the therapeutic effect in vivo. We confirmed the successful conjugation of the nanocomposite. Under 10 Gy X-rays irradiation, P-Y/G@NHs reduced the number of colonies of A549 cells, while inducing both cell apoptosis and ROS production. Moreover, P-Y/G@NHs enhanced the radiosensitivity of A549 cells by inhibiting the PI3K/AKT signaling pathway. In vivo fluorescence experiments validated that P-Y/G@NHs effectively-targeted and accumulated at the tumor site in nude mice, thus augmenting the radiosensitivity of tumors without significant immune toxicity or side effects. Conclusively, our findings highlighted that P-Y/G@NHs significantly enhanced the radiosensitivity of NSCLC cells by repressing the PI3K/AKT signaling pathway.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas Metálicas , Animais , Camundongos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos Nus , Espécies Reativas de Oxigênio/metabolismo , Ouro/farmacologia , Linhagem Celular Tumoral , Transdução de Sinais , Apoptose , Proliferação de Células
8.
Molecules ; 28(2)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36677583

RESUMO

The dopamine D3 receptor (D3R) is an important central nervous system target for treating various neurological diseases. D3R antagonists modulate the improvement of psychostimulant addiction and relapse, while D3R agonists can enhance the response to dopaminergic stimulation and have potential applications in treating Parkinson's disease, which highlights the importance of identifying novel D3R ligands. Therefore, we performed auto dock Vina-based virtual screening and D3R-binding-affinity assays to identify human D3R ligands with diverse structures. All molecules in the ChemDiv library (>1,500,000) were narrowed down to a final set of 37 molecules for the binding assays. Twenty-seven compounds exhibited over 50% inhibition of D3R at a concentration of 10 µM, and 23 compounds exhibited over 70% D3R inhibition at a concentration of 10 µM. Thirteen compounds exhibited over 80% inhibition of D3R at a concentration of 10 µM and the IC50 values were measured. The IC50 values of the five compounds with the highest D3R-inhibition rates ranged from 0.97 µM to 1.49 µM. These hit compounds exhibited good structural diversity, which prompted us to investigate their D3R-binding modes. After trial and error, we combined unbiased molecular dynamics simulation (MD) and molecular mechanics generalized Born surface area (MM/GBSA) binding free-energy calculations with the reported protein−ligand-binding pose prediction method using induced-fit docking (IFD) and binding pose metadynamics (BPMD) simulations into a self-consistent and computationally efficient method for predicting and verifying the binding poses of the hit ligands to D3R. Using this IFD-BPMD-MD-MM/GBSA method, we obtained more accurate and reliable D3R−ligand-binding poses than were obtained using the reported IFD-BPMD method. This IFD-BPMD-MD-MM/GBSA method provides a novel paradigm and reference for predicting and validating other protein−ligand binding poses.


Assuntos
Proteínas , Receptores de Dopamina D3 , Humanos , Ligantes , Sítios de Ligação , Receptores de Dopamina D3/química , Simulação de Acoplamento Molecular , Ligação Proteica , Proteínas/metabolismo
9.
Chemistry ; 28(2): e202103543, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34730859

RESUMO

A series of [-2, -1, 0] charged-ligand based iridium(III) complexes of [Ir(bph)(bpy)(acac)] (1), [Ir(bph)(2MeO-bpy)(acac)] (2), [Ir(bph)(2CF3 -bpy)(acac)] (3), [Ir(bph)(bpy)(2t Bu-acac)] (4) and [Ir(bph)(bpy)(CF3 -acac)] (5), which using biphenyl as dianionic ligand [-2], acetylacetone (or its derivatives) as monoanionic ligand [-1], and 2,2'-bipyridine (or its derivatives) as neutral ligand [0] were designed and synthesized. The chemical structures were well characterized. All of the ligands have simple chemical structures, thus further making the complexes have excellent thermal stability and are easy to sublimate and purify. Phosphorescent characteristics with short emission lifetime were demonstrated for these emitters. Notably, all of the complexes exhibit remarkable deep red/near infrared emission, which is quite different from the reported [-1, -1, -1] charged-ligand based iridium(III) complexes. The photophysical properties of these complexes are regularly improved by introducing electron-donating or -withdrawing groups into [-1] or [0] charged-ligand. The related organic light-emitting diodes exhibited deep red/near infrared emission with acceptable external quantum efficiency and low turn-on voltage (<2.6 V). This work provides a new idea for the construction of new type phosphorescent iridium(III) emitters with different valence states of [-2, -1, 0] charged ligands, thus offering new opportunities and challenges for their optoelectronic applications.

10.
Arch Virol ; 167(2): 563-570, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34860285

RESUMO

We have determined the effect of seven serine- and arginine-rich (SR) proteins and 15 heterogenous nuclear ribonucleoproteins (hnRNPs) on human papillomavirus type 16 (HPV16) late gene expression. Of the seven SR proteins analyzed here, SRSF1, SRSF3, and SRSF9 induced HPV16 late gene expression, and five of the SR proteins affected HPV16 L1 mRNA splicing. Of the 15 hnRNP proteins analyzed here, hnRNP A2, hnRNP F, and hnRNP H efficiently induced HPV16 late gene expression, and all of the hnRNPs affected HPV16 L1 mRNA levels or mRNA splicing. Thus, the majority of SR proteins and hnRNPs have the potential to regulate HPV16 L1 mRNA splicing. Strict control of the expression of the immunogenic L1 and L2 capsid proteins may contribute to the ability of HPV16 to cause persistence.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas , Serina , Arginina , Expressão Gênica , Regulação Viral da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/metabolismo , Humanos , RNA Mensageiro/genética , Ribonucleoproteínas/metabolismo , Fatores de Processamento de Serina-Arginina/genética
11.
J Virol ; 94(20)2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32759322

RESUMO

Human papillomavirus 16 (HPV16) 5'-splice site SD226 and 3'-splice site SA409 are required for production of the HPV16 E7 mRNAs, whereas unspliced mRNAs produce E6 mRNAs. The E6 and E7 proteins are essential in the HPV16 replication cycle but are also the major HPV16 proteins required for induction and maintenance of malignancy caused by HPV16 infection. Thus, a balanced expression of unspliced and spliced mRNAs is required for production of sufficient quantities of E6 and E7 proteins under physiological and pathophysiological conditions. If splicing becomes too efficient, the levels of unspliced E6 mRNAs will decrease below a threshold level that is no longer able to produce E6 protein quantities high enough to significantly reduce p53 protein levels. Similarly, if splicing becomes too inefficient, the levels of spliced E7 mRNAs will decrease below a threshold level that is no longer able to produce E7 protein quantities high enough to significantly reduce pRb protein levels. To determine how splicing between SD226 and SA409 is regulated, we have investigated how SA409 is controlled by the cellular proteins hnRNP A1 and hnRNP A2, two proteins that have been shown previously to control HPV16 gene expression. We found that hnRNP A1 and A2 interacted directly and specifically with a C-less RNA element located between HPV16 nucleotide positions 594 and 604 downstream of SA409. Overexpression of hnRNP A1 inhibited SA409 and promoted production of unspliced E6 mRNAs at the expense of the E7 mRNAs, whereas overexpression of hnRNP A2 inhibited SA409 to redirect splicing to SA742, a downstream 3'-splice site that is used for generation of HPV16 E6̂E7, E1, and E4 mRNAs. Thus, high levels of either hnRNP A1 or hnRNP A2 inhibited production of the promitotic HPV16 E7 protein. We show that the hnRNP A1 and A2 proteins control the relative levels of the HPV16 unspliced and spliced HPV16 E6 and E7 mRNAs and function as inhibitors of HPV16 E7 expression.IMPORTANCE Human papillomavirus type 16 (HPV16) belongs to the high-risk-group of HPVs and is causing a variety of anogenital cancers and head and neck cancer. The two HPV16 oncoproteins E6 and E7 prevent apoptosis and promote mitosis and are essential for completion of the HPV16 life cycle and for transformation of the infected cell and maintenance of malignancy. E6 and E7 are produced from two mRNAs that are generated in a mutually exclusive manner by alternative splicing. While E6 protein is made from the unspliced mRNA, E7 is made from the spliced version of the same pre-mRNA. Since sufficient quantities of both E6 and E7 are required for malignant transformation, this intricate arrangement of gene expression renders E6 and E7 expression vulnerable to external interference. Since antiviral drugs to HPV16 are not available, a detailed knowledge of the regulation of HPV16 E6 and E7 mRNA splicing may uncover novel targets for therapy.


Assuntos
Ribonucleoproteína Nuclear Heterogênea A1/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Papillomavirus Humano 16/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Splicing de RNA , RNA Viral/metabolismo , Células HeLa , Ribonucleoproteína Nuclear Heterogênea A1/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Papillomavirus Humano 16/genética , Humanos , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Proteínas E7 de Papillomavirus/genética , RNA Viral/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
12.
Molecules ; 26(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34770795

RESUMO

Three near-infrared emitters (2TPA-QBT, 2MeTPA-BT and TPA-QBT-MeTPA) were rationally designed and synthesized. Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations showed that the introduction of mono- or di-methyl groups between the donors and acceptor could result in the spatial configuration changing greatly for 2MeTPA-QBT and TPA-QBT-MeTPA compared to their parent compound 2TPA-QBT. The emission of TPA-QBT-MeTPA had a more obvious hybridized local and charge transfer feature (HLCT) based on the influence of the steric hindrance of the methyl substituent. Attributed to their different spatial configurations and luminescence mechanisms, different emission wavelengths with photoluminescent quantum yields of 26%, 38% and 34% in toluene, as well as 24%, 27% and 31% in 4,4'-bis(N-carbazolyl)-1,1'-biphenyl (CBP) doped film, were observed for 2TPA-QBT, 2MeTPA-QBT and TPA-QBT-MeTPA, respectively. The constructed organic light-emitting devices (OLEDs) displayed electroluminescence with emission peaks at 728, 693 and 710 nm, with maximum external quantum efficiencies of 1.58%, 1.33% and 3.02% for the 2TPA-QBT, 2MeTPA-QBT and TPA-QBT-MeTPA-doped OLEDs, respectively. This work illustrated the effect of spatial configuration changes on the luminescence properties of donor-acceptor-type organic emitters.

13.
Nucleic Acids Res ; 46(10): 5029-5049, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29596642

RESUMO

We show that the alkylating cancer drug melphalan activated the DNA damage response and induced human papillomavirus type 16 (HPV16) late gene expression in an ATM- and Chk1/2-dependent manner. Activation of HPV16 late gene expression included inhibition of the HPV16 early polyadenylation signal that resulted in read-through into the late region of HPV16. This was followed by activation of the exclusively late, HPV16 splice sites SD3632 and SA5639 and production of spliced late L1 mRNAs. Altered HPV16 mRNA processing was paralleled by increased association of phosphorylated BRCA1, BARD1, BCLAF1 and TRAP150 with HPV16 DNA, and increased association of RNA processing factors U2AF65 and hnRNP C with HPV16 mRNAs. These RNA processing factors inhibited HPV16 early polyadenylation and enhanced HPV16 late mRNA splicing, thereby activating HPV16 late gene expression.


Assuntos
Dano ao DNA/genética , Interações Hospedeiro-Patógeno/genética , Papillomavirus Humano 16/genética , Processamento Pós-Transcricional do RNA , Fator de Processamento U2AF/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Linhagem Celular , Fator de Especificidade de Clivagem e Poliadenilação/genética , Fator de Especificidade de Clivagem e Poliadenilação/metabolismo , DNA Viral/genética , DNA Viral/metabolismo , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Papillomavirus Humano 16/efeitos dos fármacos , Papillomavirus Humano 16/patogenicidade , Humanos , Melfalan/farmacologia , Fosforilação/efeitos dos fármacos , Poliadenilação/efeitos dos fármacos , Splicing de RNA/efeitos dos fármacos , Fator de Processamento U2AF/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
14.
Genomics ; 111(4): 629-635, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-29626511

RESUMO

Salt stress causes foliar chlorosis and scorch, plant stunting, and eventually yield reduction in soybean. There are differential responses, namely tolerance (excluder) and intolerance (includer), among soybean germplasm. However, the genetic and physiological mechanisms for salt tolerance is complex and not clear yet. Based on the results from the screening of the RA-452 x Osage mapping population, two F4:6 lines with extreme responses, most tolerant and most sensitive, were selected for a time-course gene expression study in which the 250 mM NaCl treatment was initially imposed at the V1 stage and continued for 24 h (hrs). Total RNA was isolated from the leaves harvested at 0, 6, 12, 24 h after the initiation of salt treatment, respectively. The RNA-Seq analysis was conducted to compare the salt tolerant genotype with salt sensitive genotype at each time point using RNA-Seq pipeline method. A total of 2374, 998, 1746, and 630 differentially expressed genes (DEGs) between salt-tolerant line and salt-sensitive line, were found at 0, 6, 12, and 24 h, respectively. The expression patterns of 154 common DEGs among all the time points were investigated, of which, six common DEGs were upregulated and seven common DEGs were downregulated in salt-tolerant line. Moreover, 13 common DEGs were dramatically expressed at all the time points. Based on Log2 (fold change) of expression level of salt-tolerant line to salt-sensitive line and gene annotation, Glyma.02G228100, Glyma.03G226000, Glyma.03G031000, Glyma.03G031400, Glyma.04G180300, Glyma.04G180400, Glyma.05 g204600, Glyma.08G189600, Glyma.13G042200, and Glyma.17G173200, were considered to be the key potential genes involving in the salt-tolerance mechanism in the soybean salt-tolerant line.


Assuntos
Glycine max/genética , Tolerância ao Sal , Transcriptoma , Regulação da Expressão Gênica de Plantas , Genótipo , Glycine max/fisiologia
15.
Int J Cancer ; 144(2): 297-310, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30303514

RESUMO

Here we show that treatment of the HPV16-positive tonsillar cancer cell line HN26 with DNA alkylating cancer drug melphalan-induced p53 and activated apoptosis. Melphalan reduced the levels of RNA polymerase II and cellular transcription factor Sp1 that were associated with HPV16 DNA. The resulting inhibition of transcription caused a rapid loss of the HPV16 early mRNAs encoding E6 and E7 as a result of their inherent instability. As a consequence of HPV16 E6 and E7 down-regulation, the DNA damage inflicted on the cells by melphalan caused induction of p53 and activation of apoptosis in the HN26 cells. The BARD1-negative phenotype of the HN26 cells may have contributed to the failure to repair DNA damage caused by melphalan, as well as to the efficient apoptosis induction. Finally, nude mice carrying the HPV16 positive tonsillar cancer cells responded better to melphalan than to cisplatin, the chemotherapeutic drug of choice for tonsillar cancer. We concluded that the short half-life of the HPV16 E6 and E7 mRNAs renders HPV16-driven tonsillar cancer cells particularly sensitive to DNA damaging agents such as melphalan since melphalan both inhibits transcription and causes DNA damage.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Apoptose/efeitos dos fármacos , Melfalan/farmacologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/virologia , Neoplasias Tonsilares/virologia , Animais , Linhagem Celular Tumoral , Meia-Vida , Papillomavirus Humano 16 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Oncogênicas Virais/biossíntese , Proteínas Oncogênicas Virais/efeitos dos fármacos , Proteínas E7 de Papillomavirus/biossíntese , Proteínas E7 de Papillomavirus/efeitos dos fármacos , Infecções por Papillomavirus/complicações , Estabilidade de RNA/efeitos dos fármacos , Proteínas Repressoras/biossíntese , Proteínas Repressoras/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
BMC Cancer ; 19(1): 265, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30909875

RESUMO

BACKGROUND: Human papillomavirus (HPV) is an established risk factor for oropharyngeal squamous cell carcinoma (OSCC). The aim was to establish cell lines from HPV-positive tonsil carcinomas to be used for treatment development. METHODS: Fresh samples from 23 HPV-positive tonsil carcinomas were cultivated in vitro. The established cell line was analyzed for viral characteristics, cell karyotype, TP53 status, and growth capabilities in nude mice. In vitro studies of sensitivities to radiation, cisplatin and cetuximab were performed. RESULTS: After 19 months (eight passages), one cell line, LU-HNSCC-26, was established in vitro and also grew as xenografts. The tumor was from a 48 year old non-smoking man with non-keratinizing, p16 positive tonsil OSCC, stage T2N0M0 with HPV16. It contained 19.5 (CV% 3.7) HPV16 copies/cell (passage 8). The complete HPV16 genome sequence was obtained. Episomal HPV16 was present with an E2/E7 ratio of 1.1 (CV% 2.6). In addition, HPV16 mRNA specific for the intact E2 gene was detected. The viral expression manifested 1.0 (CV% 0.1) E7 mRNA copies per HPV16 genome. The karyotype was determined and the cell line demonstrated wild type TP53. The ID50 for radiation was 0.90 Gy and the IC50 for cisplatin was 0.99 µmol/L. The cell line was inhibited to a maximum of 18% by cetuximab. CONCLUSIONS: We established an in vitro tonsil carcinoma cell line containing episomal HPV16. This is an important step towards efficient treatment development.


Assuntos
Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral/citologia , Cisplatino/administração & dosagem , Papillomavirus Humano 16/genética , Infecções por Papillomavirus/terapia , Neoplasias Tonsilares/virologia , Animais , Linhagem Celular Tumoral/virologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Cisplatino/uso terapêutico , Genoma Viral , Papillomavirus Humano 16/efeitos dos fármacos , Papillomavirus Humano 16/efeitos da radiação , Humanos , Concentração Inibidora 50 , Cariótipo , Masculino , Camundongos , Pessoa de Meia-Idade , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , Radioterapia , Neoplasias Tonsilares/genética , Neoplasias Tonsilares/terapia , Carga Viral/efeitos dos fármacos , Carga Viral/efeitos da radiação , Sequenciamento Completo do Genoma , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Chirality ; 31(1): 72-78, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30515892

RESUMO

The high-performance liquid chromatography (HPLC) is a powerful method in the area of stereoisomer separation. In this study, separation of eight bedaquiline analogue diastereomers (compounds 1-8) was first examined on a cellulose tris-(3,5-dichlorophenylcarbamate) chiral stationary phase, ie, Chiralpak IC in the normal phase mode. The influences of organic modifier types, alcohol content, and column temperature on diastereoseparation were evaluated. Under the optimum chromatographic conditions, all the analyte stereoisomers were successfully separated. The experimental results revealed the great influence of analytes' structures on the diastereoseparation with Chiralpak IC. In addition, thermodynamic parameters were calculated by Van't Hoff plots, and correlative chiral recognition mechanisms were discussed further.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Diarilquinolinas/química , Diarilquinolinas/isolamento & purificação , 2-Propanol/química , Celulose/análogos & derivados , Celulose/química , Etanol/química , Fenilcarbamatos/química , Polissacarídeos/química , Estereoisomerismo , Temperatura
18.
Nucleic Acids Res ; 45(16): 9654-9678, 2017 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-28934469

RESUMO

Inhibition of the Akt kinase activates HPV16 late gene expression by reducing HPV16 early polyadenylation and by activating HPV16 late L1 mRNA splicing. We identified 'hot spots' for RNA binding proteins at the early polyA signal and at splice sites on HPV16 late mRNAs. We observed that hnRNP L was associated with sequences at all HPV16 late splice sites and at the early polyA signal. Akt kinase inhibition resulted in hnRNP L dephosphorylation and reduced association of hnRNP L with HPV16 mRNAs. This was accompanied by an increased binding of U2AF65 and Sam68 to HPV16 mRNAs. Furthermore, siRNA knock-down of hnRNP L or Akt induced HPV16 gene expression. Treatment of HPV16 immortalized keratinocytes with Akt kinase inhibitor reduced hnRNP L binding to HPV16 mRNAs and induced HPV16 L1 mRNA production. Finally, deletion of the hnRNP L binding sites in HPV16 subgenomic expression plasmids resulted in activation of HPV16 late gene expression. In conclusion, the Akt kinase inhibits HPV16 late gene expression at the level of RNA processing by controlling the RNA-binding protein hnRNP L. We speculate that Akt kinase activity upholds an intracellular milieu that favours HPV16 early gene expression and suppresses HPV16 late gene expression.


Assuntos
Ribonucleoproteínas Nucleares Heterogêneas Grupo L/metabolismo , Papillomavirus Humano 16/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Splicing de RNA , RNA Viral/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Sítios de Ligação , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Viral da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo D/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas Grupo L/genética , Papillomavirus Humano 16/patogenicidade , Humanos , Fosforilação , Piperazinas/farmacologia , Poliadenilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/genética , Pirimidinas/farmacologia , Sítios de Splice de RNA , RNA Mensageiro , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
19.
J Gen Virol ; 99(3): 328-343, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29458523

RESUMO

HPV16 late L1 mRNAs encode a short central exon that is located between HPV16 3'-splice site SA3358 and HPV16 5'-splice site SD3632. While SA3358 is used to produce both HPV16 early mRNAs encoding the E6 and E7 oncogenes, and late mRNAs encoding E4, L1 and L2, SD3632 is used exclusively to produce late L1 mRNA. We have previously identified an 8-nucleotide regulatory RNA element that is required for inclusion of the exon between SA3358 and SD3632 to produce L1 mRNAs at the expense of mRNAs polyadenylated at the HPV16 early polyadenylation signal pAE. Here we show that this HPV16 8-nucleotide splicing enhancer interacts with hnRNP G. Binding of hnRNP G to this element prevents inclusion of the exon between SA3358 and SD3632 on the HPV16 late L1 mRNAs. We concluded that hnRNP G has a splicing inhibitory role and that hnRNP G can control HPV16 mRNA splicing.

20.
Plant Cell Environ ; 41(9): 2169-2182, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29520811

RESUMO

Natural genetic variations in waterlogging tolerance are controlled by multiple genes mapped as quantitative trait loci (QTLs) in major crops, including soybean (Glycine max L.). In this research, 2 novel QTLs associated with waterlogging tolerance were mapped from an elite/exotic soybean cross. The subsequent research was focused on a major QTL (qWT_Gm03) with the tolerant allele from the exotic parent. This QTL was isolated into near-isogenic backgrounds, and its effects on waterlogging tolerance were validated in multiple environments. Fine mapping narrowed qWT_Gm03 into a genomic region of <380 Kbp excluding Rps1 gene for Phytophthora sojae resistance. The tolerant allele of qWT_Gm03 promotes root growth under nonstress conditions and favourable root plasticity under waterlogging, resulting in improved waterlogging tolerance, yield, and drought tolerance-related traits, possibly through more efficient water/nutrient uptakes. Meanwhile, involvement of auxin pathways was also identified in the regulation of waterlogging tolerance, as the genotypic differences of qWT_Gm03 in waterlogging tolerance and formation of adventitious/aerial roots can be complemented by an exogenous auxin-biosynthesis inhibitor. These findings provided genetic resources to address the urgent demand of improving waterlogging tolerance in soybean and revealed the determinant roles of root architecture and plasticity in the plant adaptation to waterlogging.


Assuntos
Glycine max/genética , Raízes de Plantas/anatomia & histologia , Locos de Características Quantitativas , Alelos , Mapeamento Cromossômico , Variação Genética , Ácidos Indolacéticos/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Glycine max/fisiologia , Água/metabolismo
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