RESUMO
Ribosomes that stall before completing peptide synthesis must be recycled and returned to the cytoplasmic pool. The protein Dom34 and cofactors Hbs1 and Rli1 can dissociate stalled ribosomes in vitro, but the identity of targets in the cell is unknown. Here, we extend ribosome profiling methodology to reveal a high-resolution molecular characterization of Dom34 function in vivo. Dom34 removes stalled ribosomes from truncated mRNAs, but, in contrast, does not generally dissociate ribosomes on coding sequences known to trigger stalling, such as polyproline. We also show that Dom34 targets arrested ribosomes near the ends of 3' UTRs. These ribosomes appear to gain access to the 3' UTR via a mechanism that does not require decoding of the mRNA. These results suggest that ribosomes frequently enter downstream noncoding regions and that Dom34 carries out the important task of rescuing them.
Assuntos
Regiões 3' não Traduzidas , Proteínas de Ciclo Celular/metabolismo , Endorribonucleases/metabolismo , Ribossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Diamida/farmacologia , Ensaios de Proteção de Nucleases , Biossíntese de Proteínas , Ribossomos/efeitos dos fármacosRESUMO
In order to discover new meta-diamide compounds with good activity and novel structure, 15 related compounds were designed and synthesized by the bioisosterism principle with cyproflanilide as the lead compound. The insecticidal activities of these compounds against Plutella xylostella and Tetranychus cinnabarinus were tested, and the results of biological activity test showed that some compounds had more than 90 % insecticidal activity against Plutella xylostella at 1â mg/L and Tetranychus cinnabarinus at 100â mg/L. Especially, N-(2-bromo-6-(difluoromethoxy)-4-(perfluoro propan-2-yl)phenyl)-6-(isonicotinamido)picolinamide against Tetranychus cinnabarinus at 10â mg/L was 100 %, which was better than that of cyproflanilide. Molecular docking studies suggested that N-(2-bromo-6-(difluoromethoxy)-4-(perfluoropropan-2-yl)phenyl)-6-(4-cyano-2-methylbenzamido)picolinamide had a closely combined with the Plutella xylostella 3RHW (a glutamate-gated chloride channel). This study provides an avenue for designing and synthesizing a new generation of more effective pesticides.
Assuntos
Desenho de Fármacos , Inseticidas , Simulação de Acoplamento Molecular , Mariposas , Piridinas , Tetranychidae , Inseticidas/síntese química , Inseticidas/química , Inseticidas/farmacologia , Animais , Piridinas/química , Piridinas/farmacologia , Piridinas/síntese química , Mariposas/efeitos dos fármacos , Relação Estrutura-Atividade , Tetranychidae/efeitos dos fármacos , Diamida/farmacologia , Diamida/química , Diamida/síntese química , Estrutura MolecularRESUMO
Diamide insecticides have always been a hot research topic in the field of pesticides. To further discover new compounds with high activity and safety, indane and its analogs were introduced into chlorantraniliprole, and a battery of chlorfenil derivatives, including indane and its analogs, were designed and prepared for biological testing. Their characterization and verification were carried out through nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS). Biological detection showed that all the compounds exhibited good insecticidal activity against Mythimna separata. At 0.8 mg/L, the insecticidal activity of compound 8q against Mythimna separata was 80%, which was slightly better than that of chlorantraniliprole. The results of the structure-activity relationship (SAR) analysis indicated that the indane moiety had a significant effect on insecticidal activity, especially in the R-configuration. The results indicated that chlorantraniliprole derivatives containing indane groups could serve as pilot compounds for the further development of new insecticides.
Assuntos
Inseticidas , Mariposas , ortoaminobenzoatos , Animais , Inseticidas/química , Diamida/farmacologia , Desenho de Fármacos , Relação Estrutura-Atividade , Estrutura MolecularRESUMO
Antioxidants are widely used in medicine due to their ability to bind free radicals - active biomolecules that destroy the genetic apparatus of cells and the structure of their membranes, which makes it possible to reduce the intensity of oxidative processes in the body. In a living organism, free radicals are involved in various processes, but their activity is controlled by antioxidants. The purpose of this work was to conduct a series of studies to identify the antioxidant activity of new synthesized compounds of a series of oxalic acid diamides in the brain and liver tissue of white rats in vivo and in vitro experiments, as well as to determine their potential pharmacological properties. The studies were conducted on outbred white male rats, weighing 180-200 g, kept on a normal diet. After autopsy, the brain and liver were isolated, washed with saline, cleared of blood vessels, and homogenized in Tris-HCl buffer (pH-7.4) (in vitro). The research results showed significant antioxidant activity (AOA) of all compounds with varying effectiveness. The most pronounced activity was demonstrated by compound SV-425 in both brain and liver tissues. Compound SV-427 demonstrated the least activity, with levels in brain tissue and liver tissue. In addition, all physicochemical descriptors of the studied compounds comply with Lipinski's rule of five to identify new molecules for the treatment of oxidative stress. From the data obtained, it can be concluded that the studied compounds have antioxidant properties, helping to protect cells from oxidative stress. This is important for the prevention and treatment of diseases associated with increased levels of free radicals.
Assuntos
Antioxidantes , Encéfalo , Peroxidação de Lipídeos , Fígado , Ácido Oxálico , Animais , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Masculino , Ratos , Antioxidantes/farmacologia , Antioxidantes/química , Radicais Livres/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Ácido Oxálico/química , Ácido Oxálico/metabolismo , Ácido Oxálico/farmacologia , Diamida/farmacologia , Diamida/química , Estresse Oxidativo/efeitos dos fármacos , Oxirredução/efeitos dos fármacosRESUMO
As a Lepidoptera pest, Spodoptera frugiperda has become one of the major migratory pests causing significant damage to crops. It should prevent and control Spodoptera frugiperda with strong reproductive ability, adaptability, and migration ability, and reduce economic losses as much as possible. Chemical insecticides are mainly used in the emergency control of Spodoptera frugiperda. Diamide insecticide is a kind of pesticide that specifically targets the ryanodine receptor of Lepidopteran pests, which makes it safe, effective, targeted, and low toxicity to mammals. So, it is one of the most concerned and fastest-growing pesticide products after neonicotinoid pesticides. Intracellular Ca2+ concentration can be regulated by ryanodine receptors, and the continuous release of Ca2+ eventually leads to the death of pests and achieve the insecticidal effect. This review introduces in detail diamide insecticides that mainly play roles in stomach toxicity, as well as its specific target-ryanodine receptor, and analyzes how the diamide insecticide acts on the ryanodine receptor and how its mechanism of action can provide a theoretical basis for the rational use of highly effective insecticides and solve the resistance problem. Moreover, we also propose several recommendations for reducing resistance to diamide insecticides, and provide a reference for chemical control and resistance studies of Spodoptera frugiperda, which has broad development prospects in today's increasingly concerned about the ecological environment and advocating green environmental protection.
Assuntos
Inseticidas , Animais , Inseticidas/toxicidade , Canal de Liberação de Cálcio do Receptor de Rianodina , Diamida/farmacologia , Resistência a Inseticidas , Spodoptera , MamíferosRESUMO
BACKGROUND: Chlorantraniliprole is a diamide insecticide widely used in China over the last 15 years. The fall armyworm (FAW), Spodoptera frugiperda, newly invaded China in 2019. The response of FAW to chlorantraniliprole deserves more attention, in the context of many destructive lepidopteran species are resistant to diamide insecticides and the patent on core chemical of chlorantraniliprole in China expired in August 2022. METHODS AND RESULTS: This study investigated the response profile in larvae under chlorantraniliprole-induced (LC50) stress using methods of bioassay, RNA-Seq and qPCR. We observed growth inhibition and lethal effects in FAW larvae, but at a relatively high LC50 value compared to other several pests. Additionally, under chlorantraniliprole-induced stress, 3309 unigenes were found to be differentially expressed genes. The impacted genes included 137 encoding for detoxification enzymes, 29 encoding for cuticle proteins, and 20 key enzymes involved in the chitin metabolism, which all associated with metabolic resistance. Finally, we obtained the single nucleotide polymorphisms (SNPs) of two RyR genes, which are the target proteins for chlorantraniliprole. We also investigated the causes of the high LC50 value in our FAW, which possibly related to the stabilized 4743 M on SNP frequency of RyR. These findings documented the genetic background of RyR of FAW and indicated that application of chlorantraniliprole has a high risk of controlling FAW in China. CONCLUSION: In brief, our results provide a better understanding of the mechanisms of chlorantraniliprole toxicity and detoxification in FAW, and will aid in monitoring the development of resistant strains for a newly pest to an old insecticide.
Assuntos
Inseticidas , Animais , Inseticidas/toxicidade , Spodoptera/genética , Transcriptoma/genética , Diamida/farmacologia , Resistência a Inseticidas/genética , Larva/genéticaRESUMO
Covalent histone modifications are highly conserved and play multiple roles in eukaryotic transcription regulation. Here, we mapped 26 histone modifications genome-wide in exponentially growing yeast and during a dramatic transcriptional reprogramming-the response to diamide stress. We extend prior studies showing that steady-state histone modification patterns reflect genomic processes, especially transcription, and display limited combinatorial complexity. Interestingly, during the stress response we document a modest increase in the combinatorial complexity of histone modification space, resulting from roughly 3% of all nucleosomes transiently populating rare histone modification states. Most of these rare histone states result from differences in the kinetics of histone modification that transiently uncouple highly correlated marks, with slow histone methylation changes often lagging behind the more rapid acetylation changes. Explicit analysis of modification dynamics uncovers ordered sequences of events in gene activation and repression. Together, our results provide a comprehensive view of chromatin dynamics during a massive transcriptional upheaval.
Assuntos
Cromatina/genética , Diamida/farmacologia , Saccharomyces cerevisiae/genética , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica , Genoma Fúngico , Histonas/metabolismo , Dados de Sequência Molecular , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/fisiologia , Transcrição GênicaRESUMO
Since 2007, diamide insecticides have been widely used in Korea to control various types of lepidopteran pests including Spodoptera exigua. For nearly a decade, diamide resistance in field populations of S. exigua across 18 localities has been monitored using bioassays. Despite their short history of use, resistance to diamide insecticides has emerged. Based on the LC50 values, some field populations showed a higher level of resistance to chlorantraniliprole, a diamide insecticide, compared to that of the susceptible strain, although regional and temporal variations were observed. To investigate resistance at a molecular level, we examined three mutations (Y4701C, I4790M, and G4946E) in the ryanodine receptor (RyR), which is the primary mechanism underlying diamide insecticide resistance. DNA sequencing showed that only the I4790M mutation was found in most field populations. As resistance levels varied significantly despite the uniform presence of the I4790M mutation, we considered the presence of another resistance factor. Further, the I4790M mutation was also found in S. exigua specimens collected prior to the commercialization of diamide insecticides in Korea as well as in other countries, such as the USA. This finding led us to hypothesize that the I4790M mutation were predisposed in field populations owing to selection factors other than diamide use. For further clarification, we conducted whole-genome sequencing of S. exigua (449.83 Mb) and re-sequencing of 18 individual whole genomes. However, no additional non-synonymous mutations were detected in the RyR-coding region. Therefore, we concluded that the high level of diamide insecticide resistance in Korean S. exigua is not caused by mutations at the target site, RyR, but is attributed to other factors that need to be investigated in future studies.
Assuntos
Inseticidas , Canal de Liberação de Cálcio do Receptor de Rianodina , Animais , Spodoptera/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Museus , Diamida/farmacologia , Inseticidas/farmacologiaRESUMO
In this study, a series of meta-diamide compounds containing ethyl acetate group and their derivatives were designed and synthesized. Their insecticidal activities against Plutella xylostella, Spodoptera frugiperda and Alfalfa sprouts were evaluated. Preliminary bioassays showed that some of the title compounds exhibited excellent insecticidal activities. Especially compound ethyl N-(3-((2-bromo-4-(perfluoropropan-2-yl)-6-(trifluoromethyl)phenyl)carbamoyl)-2-fluorophenyl)-N-(4-cyanobenzoyl)glycinate and ethyl N-(3-((2-bromo-4-(perfluoropropan-2-yl)-6-(trifluoromethyl)phenyl)carbamoyl)-2-fluorophenyl)-N-(6-fluoronicotinoyl)glycinate showed 100 % mortality at 0.1â mg/L against Plutella xylostella and Spodoptera frugiperda, same to broflanilide. Their LC50 against Plutella xylostella is 0.286â mg/L and 0.0218â mg/L, respectively. Moreover, compound ethyl N-(3-((2-bromo-4-(perfluoropropan-2-yl)-6-(trifluoromethyl)phenyl)carbamoyl)-2-fluorophenyl)-N-(6-fluoronicotinoyl)glycinate displayed faster control efficacy than broflanilide at 0.1â mg/L. The results indicated that meta-diamide compounds containing ethyl acetate group could be developed as novel and promising insecticides.
Assuntos
Diamida , Inseticidas , Mariposas , Animais , Diamida/análogos & derivados , Diamida/farmacologia , Inseticidas/química , Inseticidas/farmacologia , Estrutura Molecular , Spodoptera , Relação Estrutura-AtividadeRESUMO
Spodoptera litura is a damaging and notorious insect pest of agricultural crops that has developed resistance to various insecticides. Broflanilide is a novel pesticide with a unique mode of action that displays high efficiency against lepidopterous larvae. We here determined the baseline susceptibility of a laboratory strain of S. litura to broflanilide and 10 other popular insecticides. Furthermore, we measured susceptibility and cross-resistance using three common insecticides in 11 field-collected S. litura populations. Broflanilide caused the highest toxicity among all tested insecticides, with the laboratory strain and all field-collected populations showing high susceptibility. Moreover, no cross-resistance was detected between broflanilide and the other tested insecticides. We subsequently evaluated the sublethal effects of broflanilide and found that treatment with the 25% lethal concentration (LC25) prolonged the development duration in the larvae, reduced the pupation rate and pupae weight, and decreased egg hatchability. Finally, the activities of three detoxifying enzymes were measured in S. litura after treatment with the LC25 dose. The results suggested that enhanced cytochrome P450 monooxygenase (P450) activity could be involved in broflanilide detoxification. Overall, these findings demonstrate the strong toxicity and significant sublethal effects of broflanilide in S. litura and suggest that increased P450 activity may be associated with broflanilide detoxification.
Assuntos
Inseticidas , Praguicidas , Animais , Praguicidas/farmacologia , Inseticidas/toxicidade , Spodoptera , Diamida/farmacologia , LarvaRESUMO
Thirty novel diamide compounds combining pyrazolyl and polyfluoro-substituted phenyl groups into alanine or 2-aminobutyric acid skeletons were designed and synthesized with pyflubumide as the lead compound to develop potent and environmentally friendly pesticides. The preliminary bioassay results indicated that the new compounds containing the para-hexa/heptafluoroisopropylphenyl moiety exhibit fungicidal, insecticidal, and acaricidal activities. This is the first time that the para-hexa/heptafluoroisopropylphenyl group is a key fragment of the fungicidal activity of new N-phenyl amide compounds. Most of the target compounds exhibited moderate to good insecticidal activity against Aphis craccivora at a concentration of 400 µg/mL, and some showed moderate activity at a concentration of 200 µg/mL; in particular, compounds I-4, II-a-10, and III-26 displayed higher than 78% lethal rates at 200 µg/mL. Compound II-a-14 exhibited a 61.1% inhibition at 200 µg/mL for Tetranychus cinnabarinus. In addition, some of the target compounds exhibited good insecticidal activities against Plutella xylostella at a concentration of 200 µg/mL; the mortalities of compounds I-1, and II-a-15 were 76.7% and 70.0%, respectively. Preliminary analysis of the structure-activity relationship (SAR) indicated that the insecticidal and acaricidal activities varied significantly depending on the type of substituent and substitution pattern. The fungicidal activity results showed that compounds I-1, II-a-10, II-a-17, and III-26 exhibited good antifungal effects. Enzymatic activity experiments and in vivo efficacy of compound II-a-10 were conducted and discussed.
Assuntos
Acaricidas , Fungicidas Industriais , Inseticidas , Mariposas , Animais , Inseticidas/farmacologia , Diamida/farmacologia , Alanina/farmacologia , Desenho de Fármacos , Relação Estrutura-Atividade , Fungicidas Industriais/farmacologia , Estrutura MolecularRESUMO
The contraction and relaxation of the heart is controlled by stimulation of the ß1-adrenoreceptor (AR) signaling cascade, which leads to activation of cAMP-dependent protein kinase (PKA) and subsequent cardiac protein phosphorylation. Phosphorylation is counteracted by the main cardiac protein phosphatases, PP2A and PP1. Both kinase and phosphatases are sensitive to intramolecular disulfide formation in their catalytic subunits that inhibits their activity. Additionally, intermolecular disulfide formation between PKA type I regulatory subunits (PKA-RI) has been described to enhance PKA's affinity for protein kinase A anchoring proteins, which alters its subcellular distribution. Nitroxyl donors have been shown to affect contractility and relaxation, but the mechanistic basis for this effect is unclear. The present study investigates the impact of several nitroxyl donors and the thiol-oxidizing agent diamide on cardiac myocyte protein phosphorylation and oxidation. Although all tested compounds equally induced intermolecular disulfide formation in PKA-RI, only 1-nitrosocyclohexalycetate (NCA) and diamide induced reproducible protein phosphorylation. Phosphorylation occurred independently of ß1-AR activation, but was abolished after pharmacological PKA inhibition and thus potentially attributable to increased PKA activity. NCA treatment of cardiac myocytes induced translocation of PKA and phosphatases to the myofilament compartment as shown by fractionation, immunofluorescence, and proximity ligation assays. Assessment of kinase and phosphatase activity within the myofilament fraction of cardiac myocytes after exposure to NCA revealed activation of PKA and inhibition of phosphatase activity thus explaining the increase in phosphorylation. The data suggest that the NCA-mediated effect on cardiac myocyte protein phosphorylation orchestrates alterations in the kinase/phosphatase balance.
Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Miócitos Cardíacos/efeitos dos fármacos , Oxidantes/farmacologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Receptores Adrenérgicos beta 1/metabolismo , Transdução de Sinais , Acetatos/farmacologia , Animais , Bovinos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Diamida/farmacologia , Humanos , Masculino , Camundongos , Miócitos Cardíacos/metabolismo , Compostos Nitrosos/farmacologia , Oxirredução , Fosfoproteínas Fosfatases/metabolismo , Fosforilação/efeitos dos fármacos , Coelhos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacosRESUMO
The protozoan Plasmodium falciparum is the main aetiological agent of tropical malaria. Characteristic of the phylum is the presence of a plastid-like organelle which hosts several homologs of plant proteins, including a ferredoxin (PfFd) and its NADPH-dependent reductase (PfFNR). The PfFNR/PfFd redox system is essential for the parasite, while mammals share no homologous proteins, making the enzyme an attractive target for novel and much needed antimalarial drugs. Based on previous findings, three chemically reactive residues important for PfFNR activity were identified: namely, the active-site Cys99, responsible for hydride transfer; Cys284, whose oxidation leads to an inactive dimeric form of the protein; and His286, which is involved in NADPH binding. These amino acid residues were probed by several residue-specific reagents and the two cysteines were shown to be promising targets for covalent inhibition. The quantitative and qualitative description of the reactivity of few compounds, including a repurposed drug, set the bases for the development of more potent and specific antimalarial leads.
Assuntos
Inibidores Enzimáticos/farmacologia , Ferredoxina-NADP Redutase/antagonistas & inibidores , Malária Falciparum/prevenção & controle , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/antagonistas & inibidores , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/metabolismo , Antineoplásicos Alquilantes/farmacologia , Biocatálise/efeitos dos fármacos , Carmustina/química , Carmustina/metabolismo , Carmustina/farmacologia , Domínio Catalítico , Cisteína/química , Cisteína/metabolismo , Diamida/química , Diamida/metabolismo , Diamida/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Ferredoxina-NADP Redutase/química , Ferredoxina-NADP Redutase/metabolismo , Cinética , Malária Falciparum/parasitologia , Estrutura Molecular , NADP/metabolismo , Compostos Organomercúricos/química , Compostos Organomercúricos/metabolismo , Compostos Organomercúricos/farmacologia , Plasmodium falciparum/enzimologia , Plasmodium falciparum/fisiologia , Ligação Proteica , Domínios Proteicos , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismo , Especificidade por SubstratoRESUMO
MAIN CONCLUSION: The plasma membrane H+-ATPase can be considered as a redox-dependent enzyme, because diamide-mediated inhibition of its hydrolytic and transport activities is accompanied by alkalization of the rhizosphere and retardation of root growth. Plasma membranes were isolated from roots of etiolated pea seedlings treated in the presence of an oxidant-diamide and an inhibitor of redox-sensitive protein phosphatase-phenylarsine oxide. Hydrolytic and proton transport activities of H+-ATPase were determined. The effects of diamide appeared in inhibition of both ATP hydrolysis and the proton transport. However, root treatment with phenylarsine oxide only slightly reduced Vmax, but did not affect ATP-dependent proton transport. The thiol groups of cysteines in the proteins can act as molecular targets for both compounds. However, treatment of isolated membranes with diamide or dithiothreitol did not have any effect on the H+ transport. It can be assumed that water-soluble diamide acts indirectly and its effects are not associated with oxidation of H+-ATPase cysteines. Therefore, plasmalemma was subjected to PEGylation-process where reduced cysteines available for PEG maleimide (5 kDa) were alkylated. Detection of such cysteines was carried out by Western blot analysis with anti-ATPase antibodies. It was found that shifts in the apparent molecular weight were detected only for denaturated proteins. These data suggest that available thiols are not localized on the enzyme surfaces. BN-PAGE analysis showed that the molecular weights of the ATPase complexes are almost identical in all samples. Therefore, oligomerization is probably not the reason for the inhibition of ATPase activity. Roots treated with these inhibitors in vivo exhibited stunted growth; however, a strong alkaline zone around the roots was formed only in the presence of diamide. Involvement of H+-ATPase redox regulation in this process is discussed.
Assuntos
Diamida , Pisum sativum , Raízes de Plantas , ATPases Translocadoras de Prótons , Membrana Celular/enzimologia , Diamida/farmacologia , Pisum sativum/enzimologia , Raízes de Plantas/enzimologia , ATPases Translocadoras de Prótons/metabolismo , Plântula/efeitos dos fármacos , Plântula/enzimologiaRESUMO
Many studies have investigated how trehalose glycolipid structures can be modified to improve their Macrophage inducible C-type lectin (Mincle)-mediated adjuvanticity. However, in all instances, the ester-linkage of α,ά-trehalose to the lipid of choice remained. We investigated how changing this ester-linkage to an amide influences Mincle signalling and agonist activity and demonstrated that Mincle tolerates this functional group change. In in vivo vaccination studies in murine and ovine model systems, using OVA or Mannheimia haemolytica and Mycoplasma ovipneumoniae as vaccine antigens, respectively, it was demonstrated that a representative trehalose diamide glycolipid was able to enhance antibody-specific immune responses. Notably, IgG titres against M. ovipneumoniae were significantly greater when using trehalose dibehenamide (A-TDB) compared to trehalose dibehenate (TDB). This is particularly important as infection with M. ovipneumoniae predisposes sheep to pneumonia.
Assuntos
Especificidade de Anticorpos/efeitos dos fármacos , Antígenos/imunologia , Diamida/química , Glicolipídeos/química , Glicolipídeos/farmacologia , Lectinas Tipo C/metabolismo , Proteínas de Membrana/metabolismo , Adjuvantes Imunológicos/síntese química , Adjuvantes Imunológicos/farmacologia , Animais , Diamida/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Lectinas Tipo C/agonistas , Lectinas Tipo C/genética , Proteínas de Membrana/agonistas , Proteínas de Membrana/genética , Camundongos , Ovalbumina/imunologiaRESUMO
Alterations to amino acid residues G4946 and I4790, associated with resistance to diamide insecticides, suggests a location of diamide interaction within the pVSD voltage sensor-like domain of the insect ryanodine receptor (RyR). To further delineate the interaction site(s), targeted alterations were made within the same pVSD region on the diamondback moth (Plutella xylostella) RyR channel. The editing of five amino acid positions to match those found in the diamide insensitive skeletal RyR1 of humans (hRyR1) in order to generate a human-Plutella chimeric construct showed that these alterations strongly reduce diamide efficacy when introduced in combination but cause only minor reductions when introduced individually. It is concluded that the sites of diamide interaction on insect RyRs lie proximal to the voltage sensor-like domain of the RyR and that the main site of interaction is at residues K4700, Y4701, I4790 and S4919 in the S1 to S4 transmembrane domains.
Assuntos
Diamida/química , Proteínas de Insetos/química , Canal de Liberação de Cálcio do Receptor de Rianodina/química , Animais , Sítios de Ligação , Cafeína/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Diamida/metabolismo , Diamida/farmacologia , Humanos , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Resistência a Inseticidas/efeitos dos fármacos , Inseticidas/química , Inseticidas/metabolismo , Inseticidas/farmacologia , Mariposas/metabolismo , Mutagênese Sítio-Dirigida , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , ortoaminobenzoatos/química , ortoaminobenzoatos/metabolismo , ortoaminobenzoatos/farmacologiaRESUMO
Alternative splicing of the pyruvate kinase M (PKM) pre-mRNA generates two isoforms, PKM1 and PKM2. PKM catalyzes the conversion of phosphoenol-pyruvate to pyruvate in glycolytic pathway. PKM1 exist as a stable tetramer that is at an active enzyme state, while PKM2 is in equilibrium among monomer, dimer and tetramer under the regulation of its allosteric activators. Many cancer cells show the feature of higher glucose uptake and lactate production in spite of oxygen availability, which is known as the Warburg effect. PKM2 is upregulated in most cancer types and the inactive PKM2 lead to the cancer metabolism. In addition, dimeric PKM2 induces its nuclear translocation through posttranslational modification and acts as a transcriptional co-activator for the expression of oncogenes. Therefore, it is important to elucidate mechanisms for modulation of an active or inactive state of PKM2, namely the tetramer-to-dimer-transition. The definitive difference between PKM1 and PKM2 is to constitutively form tetramer or not in the cytoplasm, which is ascribed to 22 amino acids derived from exon 9 (PKM1) or exon 10 (PKM2). In this study, we generated 22 different PKM1-mimetic point mutants of PKM2, and demonstrated that replacement of cysteine424 residue of PKM2 with leucine424 conserved in PKM1 (C424L) promote its tetramerization. PKM2(C424L) formed a tetramer without allosteric activator, and escaped the inhibitory effects by oxidative stress, like PKM1. Our findings intensely suggest that C424 or L424 determines the different catalytic and modulatory properties between PKM splicing isoforms.
Assuntos
Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Cisteína/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Estresse Oxidativo , Multimerização Proteica , Hormônios Tireóideos/química , Hormônios Tireóideos/metabolismo , Sequência de Aminoácidos , Diamida/farmacologia , Células HeLa , Humanos , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Mutação/genética , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Multimerização Proteica/efeitos dos fármacos , Relação Estrutura-Atividade , Proteínas de Ligação a Hormônio da TireoideRESUMO
Monoacylglycerol lipase (MAGL) has emerged as an attractive drug target because of its important role in regulating the endocannabinoid 2-arachidonoylglycerol (2-AG) and its hydrolysis product arachidonic acid (AA) in the brain. Herein, we report the discovery of a novel series of diazetidinyl diamide compounds 6 and 10 as potent reversible MAGL inhibitors. In addition to demonstrating potent MAGL inhibitory activity in the enzyme assay, the thiazole substituted diazetidinyl diamides 6d-l and compounds 10 were also effective at increasing 2-AG levels in a brain 2-AG accumulation assay in homogenized rat brain. Furthermore, selected compounds have been shown to achieve good brain penetration after oral administration in an animal study.
Assuntos
Diamida/farmacologia , Descoberta de Drogas , Inibidores Enzimáticos/farmacologia , Monoacilglicerol Lipases/antagonistas & inibidores , Animais , Diamida/síntese química , Diamida/química , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Monoacilglicerol Lipases/metabolismo , Ratos , Relação Estrutura-Atividade , Distribuição TecidualRESUMO
The therapy of chronic hepatitis C virus infections has significantly improved with the development of direct-acting antivirals (DAAs), which contain NS3/4A protease, NS5A, and NS5B polymerase inhibitors. However, mutations in specific residues in these viral target genes are associated with resistance to the DAAs. Especially inhibitors of NS3/4A protease and NS5A, such as grazoprevir and velpatasvir, have a low barrier to resistant mutations. As a result, the mutations influence the virological outcomes after DAA treatment. CypA inhibitors, as host-targeted agents, act on host factors to inhibit HCV replication, exhibiting a high resistance barrier and pan-genotype activities against HCV. Therefore, they can be developed into alternative, more effective anti-HCV agents. However, CypA inhibitors are natural products and analogs. Based on previous studies, bisamide derivatives were designed and synthesized to develop a novel class of CypA inhibitors. Bisamide derivative 7c is a promising compound with potent anti-HCV activity at subtoxic concentrations. Surface plasmon resonance experiments revealed that 7c directly binds to CypA. All these studies indicated that the derivative 7c is a potent CypA inhibitor, which can be used as a host-targeted agent in combination with other antiviral agents for anti-HCV treatment.
Assuntos
Antivirais/farmacologia , Ciclofilina A/antagonistas & inibidores , Diamida/farmacologia , Inibidores Enzimáticos/farmacologia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Terapia de Alvo Molecular , Antivirais/síntese química , Antivirais/química , Linhagem Celular Tumoral , Ciclofilina A/genética , Ciclofilina A/metabolismo , Diamida/síntese química , Diamida/química , Relação Dose-Resposta a Droga , Desenvolvimento de Medicamentos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Hepatite C Crônica/metabolismo , Humanos , Conformação Molecular , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Ressonância de Plasmônio de SuperfícieRESUMO
Diamide insecticides, such as chlorantraniliprole, cyantraniliprole, and tetrachlorantraniliprole, are a new class of insecticides that selectively target insects by affecting calcium homeostasis. While this class of insecticides are effective on a wide range of insect pests, the toxicities of diamide insecticides vary among species and life stages. In this study, we addressed the mechanism underlying the different responses of Plutella xylostella and Pieris rapae to diamide insecticides. The susceptibility to insecticides of P. xylostella and P. rapae larvae was assessed 2 and 4 days after exposure to chlorantraniliprole, cyantraniliprole, and tetrachlorantraniliprole. P. xylostella larvae treated with distilled water (Group A), chlorantraniliprole (Group B), cyantraniliprole (Group C), and tetrachlorantraniliprole (Group D) and P. rapae larvae treated with distilled water (Group E), chlorantraniliprole (Group F), cyantraniliprole (Group G) and tetrachlorantraniliprole (Group H) were subjected to metabolomics analysis. The differential metabolites in the B vs. F, C vs. G, and D vs. H groups were analyzed, followed by pathway enrichment analysis. Chlorantraniliprole, cyantraniliprole, and tetrachlorantraniliprole all showed high toxicities for P. xylostella and P. rapae larvae. P. rapae larvae were more sensitive to the diamide insecticides than P. xylostella larvae. There were 65 overlapped differential metabolites between P. xylostella and P. rapae larvae treated with these three diamide insecticides. Pathway analysis showed that the differential metabolites were closely related with fatty acid biosynthesis and metabolism-related pathways. The differential regulation of fatty acid biosynthesis and metabolism may contribute to the different response to diamide insecticides in P. xylostella and P. rapae.