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The modification of RNA through the N6-methyladenosine (m6A) has emerged as a growing area of research due to its regulatory role in gene expression and various biological processes regulating the expression of genes. m6A RNA methylation is a post-transcriptional modification that is dynamic and reversible and found in mRNA, tRNA, rRNA, and other non-coding RNA of most eukaryotic cells. It is executed by special proteins known as "writers," which initiate methylation; "erasers," which remove methylation; and "readers," which recognize it and regulate the expression of the gene. Modification by m6A regulates gene expression by affecting the splicing, translation, stability, and localization of mRNA. Aging causes molecular and cellular damage, which forms the basis of most age-related diseases. The decline in skeletal muscle mass and functionality because of aging leads to metabolic disorders and morbidities. The inability of aged muscles to regenerate and repair after injury poses a great challenge to the geriatric populace. This review seeks to explore the m6A epigenetic regulation in the myogenesis and regeneration processes in skeletal muscle as well as the progress made on the m6A epigenetic regulation of aging skeletal muscles.
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Adenosina , Envelhecimento , Epigênese Genética , Músculo Esquelético , Humanos , Envelhecimento/genética , Envelhecimento/metabolismo , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Músculo Esquelético/metabolismo , Transcriptoma , Desenvolvimento Muscular/genética , MetilaçãoRESUMO
OBJECTIVES: This study aimed to understand the pharmacokinetics of ticagrelor in Chinese patients with acute coronary syndrome (ACS), identify influencing factors, and inform ticagrelor treatment optimization. MATERIALS AND METHODS: Data from 195 ACS patients, including 491 plasma ticagrelor concentration timepoints and clinical information, were analyzed using NONMEN for pharmacokinetic (PK) parameter factors. The model underwent internal validation with bootstrap methodology. RESULTS: The PK curve of ticagrelor was well delineated using a one disposition compartment model with first-order absorption rate constant, 0.67/h. When the direct bilirubin levels and white plasma cell counts increased, female patients showed decreased glomerular filtration rate, decreased ticagrelor clearance rate, and increased exposure. When the direct bilirubin levels increased and body weight and hemoglobin decreased, rs6787801 was GG compared with AA and GA, the ticagrelor metabolite clearance rate decreased and exposure increased. CONCLUSION: The study offers key insights into ticagrelor's dose-exposure relationship post-percutaneous coronary intervention in ACS patients, highlighting factors critical for personalized treatment strategies.
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Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Ticagrelor , Humanos , Ticagrelor/farmacocinética , Ticagrelor/uso terapêutico , Síndrome Coronariana Aguda/terapia , Síndrome Coronariana Aguda/tratamento farmacológico , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Povo Asiático , China , Inibidores da Agregação Plaquetária/farmacocinética , Inibidores da Agregação Plaquetária/uso terapêutico , Modelos Biológicos , Antagonistas do Receptor Purinérgico P2Y/farmacocinética , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2C19/metabolismo , Adenosina/análogos & derivados , Adenosina/farmacocinética , Adulto , População do Leste AsiáticoRESUMO
Amino acid permeases (AAPs) transporters are crucial for the long-distance transport of amino acids in plants, from source to sink. While Arabidopsis and rice have been extensively studied, research on foxtail millet is limited. This study identified two transcripts of SiAAP9, both of which were induced by NO3- and showed similar expression patterns. The overexpression of SiAAP9L and SiAAP9S in Arabidopsis inhibited plant growth and seed size, although SiAAP9 was found to transport more amino acids into seeds. Furthermore, SiAAP9-OX transgenic Arabidopsis showed increased tolerance to high concentrations of glutamate (Glu) and histidine (His). The high overexpression level of SiAAP9 suggested its protein was not only located on the plasma membrane but potentially on other organelles, as well. Interestingly, sequence deletion reduced SiAAP9's sensitivity to Brefeldin A (BFA), and SiAAP9 had ectopic localization on the endoplasmic reticulum (ER). Protoplast amino acid uptake experiments indicated that SiAAP9 enhanced Glu transport into foxtail millet cells. Overall, the two transcripts of SiAAP9 have similar functions, but SiAAP9L shows a higher colocalization with BFA compartments compared to SiAAP9S. Our research identifies a potential candidate gene for enhancing the nutritional quality of foxtail millet through breeding.
Assuntos
Arabidopsis , Retículo Endoplasmático , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Retículo Endoplasmático/metabolismo , Sementes/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Setaria (Planta)/genética , Setaria (Planta)/metabolismo , Setaria (Planta)/crescimento & desenvolvimento , Sistemas de Transporte de Aminoácidos/metabolismo , Sistemas de Transporte de Aminoácidos/genética , Transporte Proteico , Brefeldina A/farmacologia , Aminoácidos/metabolismo , Ácido Glutâmico/metabolismoRESUMO
Reactive oxygen species (ROS) is a chemically reactive chemical substance containing oxygen and a natural by-product of normal oxygen metabolism. Excessive ROS affect the growth process of crops, which will lead to the decrease of yield. Nitrogen, as a critical nutrient element in plants and plays a vital role in plant growth and crop production. Nitrate is the primary nitrogen source available to plants in agricultural soil and various natural environments. However, the molecular mechanism of ROS-nitrate crosstalk is still unclear. In this study, we used the foxtail millet (Setaria italica L.) as the material to figure it out. Here, we show that excessive NaCl inhibits nitrate-promoted plant growth and nitrogen use efficiency (NUE). NaCl induces ROS accumulation in roots, and ROS inhibits nitrate-induced gene expression in a short time. Surprisingly, low concentration ROS slight promotes and high concentration of ROS inhibits foxtail millet growth under long-term H2O2 treatment. These results may open a new perspective for further exploration of ROS-nitrate signaling pathway in plants.
Assuntos
Nitratos , Setaria (Planta) , Espécies Reativas de Oxigênio , Nitratos/farmacologia , Setaria (Planta)/genética , Peróxido de Hidrogênio , Cloreto de Sódio , Oxigênio , Transdução de Sinais , Perfilação da Expressão Gênica , NitrogênioRESUMO
Multiple epigenetic factors play a regulatory role in maintaining the homeostasis of cutaneous components and are implicated in the aging process of the skin. They have been associated with the activation of the senescence program, which is the primary contributor to age-related decline in the skin. Senescent species drive a series of interconnected processes that impact the immediate surroundings, leading to structural changes, diminished functionality, and heightened vulnerability to infections. Geroprotective medicines that may restore the epigenetic balance represent valid therapeutic alliances against skin aging. Most of them are well-known Western medications such as metformin, nicotinamide adenine dinucleotide (NAD+), rapamycin, and histone deacetylase inhibitors, while others belong to Traditional Chinese Medicine (TCM) remedies for which the scientific literature provides limited information. With the help of the Geroprotectors.org database and a comprehensive analysis of the referenced literature, we have compiled data on compounds and formulae that have shown potential in preventing skin aging and have been identified as epigenetic modulators.
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Epigênese Genética , Envelhecimento da Pele , Humanos , Epigênese Genética/efeitos dos fármacos , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/genética , Animais , Pele/metabolismo , Pele/efeitos dos fármacos , Medicina Tradicional Chinesa/métodos , Substâncias Protetoras/farmacologiaRESUMO
Human umbilical cord mesenchymal stem cells (hUMSCs) belong to a multipotent stem cell population. Transplantation of icariin (ICA)-treated hUMSCs have better tissue repairing function in chronic liver injury. This study was to investigate whether the tissue-repairing effects and migration of hUMSCs after ICA treatment were regulated by circular RNAs (circRNAs). ICA was used to treat hUMSCs in vitro for 1 week and the expression profiles of circRNAs were generated using RNA sequencing. Differentially expressed circRNAs in hUMSCs after ICA intervention were screened. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis were carried out to predict the potential function of dysregulated circRNAs. There were 52 differentially expressed circRNAs (32 circRNAs up-regulated and 20 circRNAs down-regulated) with fold changeâ ≥2.0 before and after ICA treatment. ADP-ribosylation factors were associated with the dysregulated circRNAs among Gene Ontology analysis. Kyoto Encyclopedia of Genes and Genomes analysis showed that only endocytosis pathway was associated with up-regulated circRNAs, whereas 4 pathways including homologous recombination, RNA transport, axon guidance, and proteoglycans in cancer were related to down-regulated circRNAs. Fifty-two differentially expressed circRNAs and 238 predicted microRNAs were included in circRNAs-microRNAs network. The mechanism of ICA inducing hUMSCs migration may be through regulating circRNAs expression which affects ADP-ribosylation factors protein signal pathways.
Assuntos
Flavonoides , Células-Tronco Mesenquimais , MicroRNAs , Humanos , RNA Circular/genética , MicroRNAs/genética , Cordão Umbilical , Fatores de Ribosilação do ADP/genética , Perfilação da Expressão GênicaRESUMO
The coordinated metabolism of carbon and nitrogen is essential for optimal plant growth and development. Nitrate is an important molecular signal for plant adaptation to a changing environment, but how nitrate regulates plant growth under carbon deficiency conditions remains unclear. Here we show that the evolutionarily conserved energy sensor SnRK1 negatively regulates the nitrate signalling pathway. Nitrate promoted plant growth and downstream gene expression, but such effects were repressed when plants were grown under carbon deficiency conditions. Mutation of KIN10, the α-catalytic subunit of SnRK1, partially suppressed the inhibitory effects of carbon deficiency on nitrate-mediated plant growth. KIN10 phosphorylated NLP7, the master regulator of the nitrate signalling pathway, to promote its cytoplasmic localization and degradation. Furthermore, nitrate depletion induced KIN10 accumulation, whereas nitrate treatment promoted KIN10 degradation. Such KIN10-mediated NLP7 regulation allows carbon and nitrate availability to control optimal nitrate signalling and ensures the coordination of carbon and nitrogen metabolism in plants.
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Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Carbono/metabolismo , Regulação da Expressão Gênica de Plantas , Nitratos/metabolismo , Nitrogênio/metabolismo , Plantas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Fatores de Transcrição/metabolismoRESUMO
Nitrate is both an important nutrient and a critical signaling molecule that regulates plant metabolism, growth, and development. Although several components of the nitrate signaling pathway have been identified, the molecular mechanism of nitrate signaling remains unclear. Here, we showed that the growth-related transcription factors HOMOLOG OF BRASSINOSTEROID ENHANCED EXPRESSION2 INTERACTING WITH IBH1 (HBI1) and its three closest homologs (HBIs) positively regulate nitrate signaling in Arabidopsis thaliana. HBI1 is rapidly induced by nitrate through NLP6 and NLP7, which are master regulators of nitrate signaling. Mutations in HBIs result in the reduced effects of nitrate on plant growth and â¼22% nitrate-responsive genes no longer to be regulated by nitrate. HBIs increase the expression levels of a set of antioxidant genes to reduce the accumulation of reactive oxygen species (ROS) in plants. Nitrate treatment induces the nuclear localization of NLP7, whereas such promoting effects of nitrate are significantly impaired in the hbi-q and cat2 cat3 mutants, which accumulate high levels of H2O2. These results demonstrate that HBI-mediated ROS homeostasis regulates nitrate signal transduction through modulating the nucleocytoplasmic shuttling of NLP7. Overall, our findings reveal that nitrate treatment reduces the accumulation of H2O2, and H2O2 inhibits nitrate signaling, thereby forming a feedback regulatory loop to regulate plant growth and development.
Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Homeostase , Nitratos/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismoRESUMO
Nitrate is the main source of nitrogen for plants but often distributed heterogeneously in soil. Plants have evolved sophisticated strategies to achieve adequate nitrate by modulating the root system architecture. The nitrate acquisition system is triggered by the short mobile peptides C-TERMINALLY ENCODED PEPTIDES (CEPs) that are synthesized on the nitrate-starved roots, but induce the expression of nitrate transporters on the other nitrate-rich roots through an unclear signal transduction pathway. Here, we demonstrate that the transcription factors HBI1 and TCP20 play important roles in plant growth and development in response to fluctuating nitrate supply. HBI1 physically interacts with TCP20, and this interaction was enhanced by the nitrate starvation. HBI1 and TCP20 directly bind to the promoters of CEPs and cooperatively induce their expression. Mutation in HBIs and/or TCP20 resulted in impaired systemic nitrate acquisition response. Our solid genetic and molecular evidence strongly indicate that the HBI1-TCP20 module positively regulates the CEPs-mediated systemic nitrate acquisition.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Nitratos/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Transdução de SinaisRESUMO
Berberine (BBR), an alkaloid isolated from Rhizoma Coptidis, Cortex Phellode, and Berberis, has been widely used in the treatment of ulcerative colitis (UC). However, the mechanism of BBR on UC is unknown. In this study, we investigated the activities of T regulatory cell (Treg) and T helper 17 cell (Th17) in a dextran sulfate sodium (DSS)-induced UC mouse model after BBR administration. We also investigated the changes of gut microbiota composition using 16S rRNA analysis. We also examined whether BBR could regulate the Treg/Th17 balance by modifying gut microbiota. The mechanism was further confirmed by depleting gut microbiota through a combination of antibiotic treatment and fecal transplantations. Results showed that BBR treatment could improve the Treg/Th17 balance in the DSS-induced UC model. BBR also reduced diversity of the gut microbiota and interfered with the relative abundance of Desulfovibrio, Eubacterium, and Bacteroides. Moreover, BBR treatment did not influence the Treg/Th17 balance after the depletion of gut microbiota. Our results also revealed that fecal transplantation from BBR-treated mice could relieve UC and regulate the Treg/Th17 balance. In conclusion, our study provides evidence that BBR prevents UC by modifying gut microbiota and regulating the balance of Treg/Th17.
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At present, the main therapy for chronic renal failure (CRF) is dialysis and renal transplantation, but neither obtains satisfactory results. Human umbilical cord mesenchymal stem cells (huMSCs) are isolated from the fetal umbilical cord which has a high self-renewal and multi-directional differentiation potential. Icariin (ICA), a kidney-tonifying Chinese Medicine can enhance the multipotency of huMSCs. Therefore, this work seeks to employ the use of ICA-treated huMSCs for the treatment of chronic renal failure. Blood urea nitrogen and creatinine (Cr) analyses showed amelioration of functional parameters in ICA-treated huMSCs for the treatment of CRF rats at 3, 7, and 14 days after transplantation. ICA-treated huMSCs can obviously increase the number of cells in injured renal tissues at 3, 7, and 14 days after transplantation by optical molecular imaging system. Hematoxylin-eosin staining demonstrated that ICA-treated huMSCs reduced the levels of fibrosis in CRF rats at 14 days after transplantation. Superoxide dismutase and Malondialdehyde analyses showed that ICA-treated huMSCs reduced the oxidative damage in CRF rats. Moreover, transplantation with ICA-treated huMSCs decreased inflammatory responses, promoted the expression of growth factors, and protected injured renal tissues. Taken together, our findings suggest that ICA-treated huMSCs could improve the kidney function in CRF rats.
Assuntos
Flavonoides/farmacologia , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Células-Tronco Mesenquimais/efeitos dos fármacos , Cordão Umbilical/citologia , Animais , Células Cultivadas , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Falência Renal Crônica/metabolismo , Testes de Função Renal , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Ratos , Resultado do Tratamento , Cordão Umbilical/efeitos dos fármacosRESUMO
Human umbilical cord mesenchymal stem cells (hUMSCs) have been shown to have multiple differentiation potentials. However, a key problem is that only a small number of hUMSCs can migrate to damaged tissue after transplantation. According to "The Theory of Kidney Essence" in Traditional Chinese Medicine, some traditional Chinese medicines used for tonifying the kidneys can be applied in promoting the differentiation and migration of stem cells in vivo. Our previous study demonstrated that icariin (ICA) could up-regulate the pluripotent genes of hUMSCs in vitro and induce cell migration in mice in an acute kidney injury model in vivo. The aim of this study was to investigate the effects of ICA-induced hUMSCs in chronic liver injury (CLI) caused by carbon tetrachloride (CCl4). CLI was induced by intraperitoneal injection of CCl4. ICA-treated hUMSCs were transplanted via intra-venous injection. The animals were followed for survival, biochemistry analysis and pathology. The results show that ICA-treated hUMSCs accelerate the recovery of liver function in mice with CLI. In addition, ICA-treated hUMSCs increase the anti-oxidant activities in liver and prevent the progression to hepatic fibrosis. Moreover, ICA induces the migration of hUMSCs to the injured liver tissue. In conclusion, these data demonstrate that ICA-treated hUMSCs exhibit recovery and protective properties in the mice model of CCl4-induced CLI.
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BACKGROUND: Chinese licorice, (Glycyrrhiza uralensis Fisch.) is one of the commonly prescribed herbs in Traditional Chinese Medicine (TCM). Gancao, as commonly known in China, is associated with immune-modulating and anti-tumor potential though the mechanism of action is not well known. In this study, we investigated the in vitro immunomodulatory and antitumor potential of Glycyrrhiza uralensis polysaccharides fractions of high molecular weight (fraction A), low molecular weight (fraction B) and crude extract (fraction C). METHODS: Cell proliferation and cytotoxicity was investigated using Cell Counting kit 8 (CCK-8) on Intestinal epithelial cell line (IEC-6) and Colon carcinoma cell line (CT-26). IL-7 gene expression relative to GAPDH was analysed using Real time PCR. The stimulation and viability of T lymphocytes was determined by Trypan blue exclusion assay. RESULTS: G.uralensis polysaccharides did not inhibit proliferation of IEC-6 cells even at high concentration. The ED50 was found to be 100 µg/ml. On the other hand, the polysaccharides inhibited the proliferation of cancer cells (CT-26) at a concentration of ≤50 µg/ml. Within 72 h of treatment with the polysaccharides, expression of IL-7 gene was up-regulated over 2 times. It was also noted that, IEC-6 cells secrete IL-7 cytokine into media when treated with G.uralensis polysaccharides. The secreted IL-7 stimulated proliferation of freshly isolated T lymphocytes within 6 h. The effect of the polysaccharides were found to be molecular weight depended, with low molecular weight having a profound effect compared to high molecular weight and total crude extract. CONCLUSION: Our findings indicate that G.uralensis polysaccharides especially those of low molecular weight have a potential as anticancer agents. Of great importance, is the ability of the polysaccharides to up-regulate anticancer cytokine IL-7, which is important in proliferation and maturation of immune cells and it is associated with better prognosis in cancer. Therefore, immunomodulation is a possible mode of action of the polysaccharides in cancer therapy.
Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Glycyrrhiza uralensis/química , Interleucina-7/metabolismo , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Neoplasias do Colo , Interleucina-7/genética , Camundongos , Extratos Vegetais/química , Polissacarídeos/química , Regulação para Cima/efeitos dos fármacosRESUMO
[This corrects the article DOI: 10.1371/journal.pone.0143022.].
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Dendritic cells (DCs) are potent antigen presenting cells (APCs). They are also specialized in the induction of cytotoxic T lymphocyte mediated responses against extracellular antigens, including tumour-specific antigens, by presenting peptide-Major Histocompatibility Complex (MHC) I complexes to naïve CD8+ T cells in lymphoid tissues, a process called cross-presentation. Emerging evidence suggests that the efficiency of cross-presentation can be influenced by a unique set of microRNAs (miRNAs). Some are differentially expressed in the course of morphological and functional development of DCs while tumorigenic miRNAs (onco-miRs) can be delivered to and inserted into DCs via exosomes. The latter reprogram the miRNA repertoire of DCs, transforming them from effective APCs to negative modulators of immunity, ultimately aiding cancers to evade host immunity. On the other hand, endogenous microRNAs can influence cross-presentation either positively or negatively. In this review, we discuss the possible mechanisms by which specific miRNAs influence cross-presentation as well as the viability of manipulating the expression of miRNAs that regulate DC cross-presentation as a potential cancer immunotherapy intervention.
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Recent studies have shown that sulforaphane (SFN) selectively inhibits the growth of ALDH⺠breast cancer stem-like cells.Herein, a series of SFN analogues were synthesized and evaluated against breast cancer cell lines MCF-7 and SUM-159, and the leukemia stem cell-like cell line KG-1a. These SFN analogues were characterized by the replacement of the methyl group with heterocyclic moieties, and the replacement of the sulfoxide group with sulfide or sulfone. A growth inhibitory assay indicated that the tetrazole analogs 3d, 8d and 9d were significantly more potent than SFN against the three cancer cell lines. Compound 14c, the water soluble derivative of tetrazole sulfide 3d, demonstrated higher potency against KG-1a cell line than 3d. SFN, 3d and 14c significantly induced the activation of caspase-3, and reduced the ALDH⺠subpopulation in the SUM159 cell line, while the marketed drug doxrubicin(DOX) increased the ALDH⺠subpopulation.
Assuntos
Ácidos Heterocíclicos/síntese química , Ácidos Heterocíclicos/farmacologia , Anticarcinógenos/síntese química , Anticarcinógenos/farmacologia , Ácidos Heterocíclicos/química , Aldeído Desidrogenase/metabolismo , Anticarcinógenos/química , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Isotiocianatos/química , Células MCF-7 , SulfóxidosRESUMO
Three novel series of 1,2,3-triazole and 1,3,4-oxadiazole derivatives of imatinib were prepared and evaluated in vitro for their cytostatic effects against a human chronic myeloid leukemia (K562), acute myeloid leukemia (HL60), and human leukemia stem-like cell line (KG1a). The structure-activity relationship was analyzed by determining the inhibitory rate of each imatinib analog. Benzene and piperazine rings were necessary groups in these compounds for maintaining inhibitory activities against the K562 and HL60 cell lines. Introducing a trifluoromethyl group significantly enhanced the potency of the compounds against these two cell lines. Surprisingly, some compounds showed significant inhibitory activities against KG1a cells without inhibiting common leukemia cell lines (K562 and HL60). These findings suggest that these compounds are able to inhibit leukemia stem-like cells.
Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Mesilato de Imatinib/análogos & derivados , Mesilato de Imatinib/farmacologia , Oxidiazóis/farmacologia , Triazóis/farmacologia , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Humanos , Mesilato de Imatinib/síntese química , Mesilato de Imatinib/química , Células K562 , Estrutura Molecular , Oxidiazóis/síntese química , Oxidiazóis/química , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/químicaRESUMO
WRKY transcription factors constitute a very large family of proteins in plants and participate in modulating plant biological processes, such as growth, development and stress responses. However, the exact roles of WRKY proteins are unclear, particularly in non-model plants. In this study, Gossypium hirsutum WRKY41 (GhWRKY41) was isolated and transformed into Nicotiana benthamiana. Our results showed that overexpression of GhWRKY41 enhanced the drought and salt stress tolerance of transgenic Nicotiana benthamiana. The transgenic plants exhibited lower malondialdehyde content and higher antioxidant enzyme activity, and the expression of antioxidant genes was upregulated in transgenic plants exposed to osmotic stress. A ß-glucuronidase (GUS) staining assay showed that GhWRKY41 was highly expressed in the stomata when plants were exposed to osmotic stress, and plants overexpressing GhWRKY41 exhibited enhanced stomatal closure when they were exposed to osmotic stress. Taken together, our findings demonstrate that GhWRKY41 may enhance plant tolerance to stress by functioning as a positive regulator of stoma closure and by regulating reactive oxygen species (ROS) scavenging and the expression of antioxidant genes.
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Gossypium/fisiologia , Nicotiana/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/fisiologia , Fatores de Transcrição/genética , Secas , Gossypium/genética , Pressão Osmótica , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Tolerância ao Sal , Estresse Fisiológico , Nicotiana/genética , Fatores de Transcrição/metabolismo , Transformação Genética , Regulação para CimaRESUMO
Arginine kinases (AK) in invertebrates play the same role as creatine kinases in vertebrates. Both proteins are important for energy metabolism, and previous studies on AK focused on this attribute. In this study, the arginine kinase gene was isolated from Apis cerana cerana and was named AccAK. A 5'-flanking region was also cloned and shown to contain abundant putative binding sites for transcription factors related to development and response to adverse stress. We imitated several abiotic and biotic stresses suffered by A. cerana cerana during their life, including heavy metals, pesticides, herbicides, heat, cold, oxidants, antioxidants, ecdysone, and Ascosphaera apis and then studied the expression patterns of AccAK after these treatments. AccAK was upregulated under all conditions, and, in some conditions, this response was very pronounced. Western blot and AccAK enzyme activity assays confirmed the results. In addition, a disc diffusion assay showed that overexpression of AccAK reduced the resistance of Escherichia coli cells to multiple adverse stresses. Taken together, our results indicated that AccAK may be involved of great significance in response to adverse abiotic and biotic stresses.
Assuntos
Arginina Quinase/metabolismo , Abelhas/enzimologia , Estresse Fisiológico , Região 5'-Flanqueadora/genética , Sequência de Aminoácidos , Animais , Arginina Quinase/genética , Arginina Quinase/isolamento & purificação , Sequência de Bases , Abelhas/genética , Sítios de Ligação , Escherichia coli/metabolismo , Herbicidas/toxicidade , Metais Pesados/toxicidade , Dados de Sequência Molecular , Compostos Organotiofosforados/toxicidade , Praguicidas/toxicidade , Filogenia , Alinhamento de Sequência , Temperatura , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Transcriptoma/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacosRESUMO
Rakicidin A is a cyclic depsipeptide that has exhibited unique growth inhibitory activity against chronic myelogenous leukemia stem cells. Furthermore, rakicidin A has five chiral centers with unknown stereochemical assignment, and thus, can be represented by one of 32 possible stereoisomers. To predict the most probable stereochemistry of rakicidin A, calculations and structural comparison with natural cyclic depsipeptides were applied. A total synthesis of the proposed structure was subsequently completed and highlighted by the creation of a sterically hindered ester bond (C1-C15) through trans-acylation from an easily established isomer (C1-C13). The analytic data of the synthetic target were consistent with that of natural rakicidin A, and then the absolute configuration of rakicidin A was assigned as 2S, 3S, 14S, 15S, 16R. This work suggests strategies for the determination of unknown chiral centers in other cyclic depsipeptides, such as rakicidin B, C, D, BE-43547, and vinylamycin, and facilitates the investigations of rakicidin A as an anticancer stem cell agent.