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1.
Food Chem ; 304: 125446, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491715

RESUMO

Fused coumarins recently attracted strong scientific interest due to their potent pharmacological activities. In this study, density functional theory (DFT) calculations were performed to evaluate the antiradical activities of a series of coumarin-fused coumarins. By calculating the thermodynamic parameters, three primary mechanisms including hydrogen atom transfer (HAT), electron transfer followed by proton transfer (SET-PT) and sequential proton loss electron transfer (SPLET) were examined. It was found that in the gas and benzene phases, the studied compounds prefer to undergo HAT mechanism, while SPLET is more favored in polar media. The results also reveal the possibility of double HAT and double SPLET mechanisms for compound CC-6. Interestingly, a new polycyclic compound was generated by forming a new C5-O5' bond during the second HAT process at the 5'-OH in CC-6-R6 radical. In addition, the SPLHAT mechanism is proposed as a competitive pathway for radical scavenging by CC-4, CC-5 and CC-6.

2.
Clin Lab ; 65(10)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625364

RESUMO

BACKGROUND: Interferon-gamma release assay (T-SPOT.TB) has the theoretical possibility of discriminating TB from most non-tuberculous mycobacteria (NTM) infections, but there are limited reports on the use of T-SPOT.TB for diseases due to NTM in high TB burden country. The aim of the present study was to assess the utility of T-SPOT.TB in patients with NTM pulmonary disease. METHODS: Clinical parameters and laboratory characteristics of patients with NTM pulmonary disease between July 2011 and Jan 2017 were investigated retrospectively and comprehensively reviewed. RESULTS: A total of 127 patients with NTM pulmonary disease were retrospectively reviewed. Seven NTM species were isolated from 115 patients, and the most common species were M. intracellulare (48.7%, 56/115) and M. abscessus (34.8%, 40/115). NTM isolates were mainly prevalent in people aged 50 years or older (73.0%). The overall positive rate of T-SPOT.TB test was 29.6% (24/81). In patients infected with NTM sharing the RD1 region of Mycobacterium tuberculosis (M. TB), 50% (3/6) were positive in the T-SPOT.TB test, whereas 28.0% (21/75) was positive in the group with NTM not sharing the RD1 region of M. TB. No significant difference was detected in the positive rate of T-SPOT.TB between definite (28.3%, 15/53) and probable disease (32.1%, 9/28). CONCLUSIONS: Our data indicated a relatively high positive rate of T-SPOT.TB test in patients infected with NTM not sharing the RD1 region of M. TB. Thus, T-SPOT.TB test displays a limited ability in differentiating TB infection from NTM disease in a high TB burden country.

3.
Nat Commun ; 10(1): 4237, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530873

RESUMO

The codling moth Cydia pomonella, a major invasive pest of pome fruit, has spread around the globe in the last half century. We generated a chromosome-level scaffold assembly including the Z chromosome and a portion of the W chromosome. This assembly reveals the duplication of an olfactory receptor gene (OR3), which we demonstrate enhances the ability of C. pomonella to exploit kairomones and pheromones in locating both host plants and mates. Genome-wide association studies contrasting insecticide-resistant and susceptible strains identify hundreds of single nucleotide polymorphisms (SNPs) potentially associated with insecticide resistance, including three SNPs found in the promoter of CYP6B2. RNAi knockdown of CYP6B2 increases C. pomonella sensitivity to two insecticides, deltamethrin and azinphos methyl. The high-quality genome assembly of C. pomonella informs the genetic basis of its invasiveness, suggesting the codling moth has distinctive capabilities and adaptive potential that may explain its worldwide expansion.

4.
Insect Sci ; 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31529759

RESUMO

Grapholita molesta is one of the most destructive fruit pests distributed worldwide. Odorant receptors (ORs) located on the dendritic membrane of chemosensory neurons are deemed to be key molecules for sensing exogenous chemical signals. In this study, GmolOR9, a general OR from G. molesta, was functionally characterized. Quantitative real-time polymerase chain reaction revealed that GmolOR9 was more highly expressed in adults than in other stages, including eggs, larvae, and pupae. GmolOR9 expression was highly significantly more in the antennae of females than in those of males, and the highest level occurred in the antennae of 3-day-old female adults. GmolOR9 was broadly tuned to eight of 47 odorant components tested, including (Z)-3-hexenyl acetate, butyl propionate, ethyl hexanoate, ethyl heptanoate, 1-hexanol, (Z)-3-hexenol, 2-ethyl-1-hexanol, and linalool, by in vitro heterologous expression. Furthermore, electroantennogram responses indicated that the effects of dsOR9-injected females to (Z)-3-hexenyl acetate dramatically decreased. These results suggested that GmolOR9 might be involved in detecting host-plant volatiles. Moreover, (Z)-3-hexenyl acetate might serve as a potential attractant for the biological control of G. molesta.

5.
Chest ; 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31437432

RESUMO

BACKGROUND: The Xpert MTB/RIF (Xpert) assay has greatly improved the diagnosis of TB and identification of resistance to rifampicin (RIF). However, sensitivity of Xpert remains poor for pleural fluid detection. This study evaluated the performance of the novel next-generation Xpert MTB/RIF Ultra (Xpert Ultra) in comparison with Xpert for pleural TB diagnosis. METHODS: Patients with suspected pleural TB were enrolled consecutively in four hospitals, and pleural fluids were subjected to smear, culture, and Xpert. Defrosted pleural fluid (-80°C) was examined using Xpert Ultra. Drug susceptibility testing (DST) was conducted for all of the recovered isolates. RESULTS: In total, 317 individuals with suspected pleural TB were recruited; 208 of them were diagnosed with pleural TB according to the composite reference standard, which was composed of clinical, laboratory, histopathologic, and radiologic examination features and ≥ 12 months of follow-up data. The direct head-to-head comparison for Mycobacterium tuberculosis detection showed that Xpert Ultra (44.23%, 92 of 208) produced a higher sensitivity than culture (26.44%, 55 of 208, P < .001), Xpert (19.23%, 40 of 208, P < .001), and smear (1.44%, three of 208, P < .001). When Xpert Ultra outcomes were integrated, the percentage of definite pleural TB cases increased from 56.25% (117 of 208) to 64.90% (135 of 208). The specificities of smear, culture, Xpert, and Xpert Ultra were 100% (84 of 84), 100% (84 of 84), 98.67% (83 of 84), and 98.67% (83 of 84), respectively. Xpert Ultra was 100% concordant with phenotype DST for the detection of RIF resistance. CONCLUSIONS: Xpert Ultra has great potential in diagnosis of pleural TB and its RIF resistance, which could speed up the initiation of appropriate treatment.

7.
Environ Int ; 130: 104854, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31200156

RESUMO

In last decade, there has been a concerted effort to reduce the potential threats of honeybees' population due to exposure to neonicotinoid pesticides. A new perspective was put forward to reduce the potential ecological toxicity of neonicotinoid dinotefuran to honeybee in terms of an enantiomeric level in the study. Toxicity of dinotefuran was enantioselective, and S-dinotefuran was 41.1- to 128.4-fold more toxic than R-dinotefuran to honeybee Apis mellifera (Apis mellifera Linnaeus), whereas R-dinotefuran exhibited comparative insecticidal activities (1.7-2.4 times) to typical sucking pests Aphis gossypii and Apolygus lucorum compared to racemic mixtures. Our data suggested that use of R-dinotefuran could have a good efficacy in controlling target pests while minimizing hazard to honeybees. The mechanism for chiral specific toxicity to honeybee was further characterized by electrophysiological studies and molecular docking. S-dinotefuran appears to be more toxic by binding to α8 subunit of nAChR of Apis mellifera. The α8 also have a more stable, functional binding cavity to S-dinotefuran with a higher binding score of 7.15, primarily due to an extensive hydrogen bond network. Therefore, new chiral products with a high proportion of or an enantiomeric pure R-dinotefuran are recommended to achieve effective pests control reducing hazard to honeybee populations.

8.
J Infect ; 79(2): 153-158, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31207324

RESUMO

OBJECTIVES: The diagnosis of osteoarticular tuberculosis (TB) remains challenging and results in under- or over-diagnosis. The aim of the present study was to evaluate performance of the novel next-generation Xpert MTB/RIF Ultra (Xpert Ultra) in comparison to culture and Xpert MTB/RIF (Xpert) for osteoarticular TB diagnosis in high burden settings. METHODS: Osteoarticular TB suspected cases were enrolled consecutively during June 2017 to June 2018 at Beijing Chest Hospital and their pus specimens were subjected to smear, culture, Xpert and Xpert Ultra. Drug susceptibility testing (DST) was conducted for all of the recovered isolates. The performances of Xpert Ultra and Xpert were evaluated using composite reference standard (CRS) as gold standard, which included clinical, laboratory, histopathological, radiological and ≥6 months' follow-up data. RESULTS: In total, 186 patients were recruited, and 132 of them were diagnosed with osteoarticular TB according to CRS. The direct head-to-head performance comparison for M. tuberculosis detection showed that Xpert Ultra (90.91%, 120/132) produced a higher sensitivity than Xpert (78.79%, 104/132, P = 0.006) and culture (39.39%, 52/132, P < 0.001). When Xpert Ultra outcomes were integrated, the percentage of confirmed osteoarticular TB case increased from 84.09% (111/132) to 93.94% (124/132). The specificities of Xpert and Xpert Ultra were 100% (34/34) and 97.06% (33/34), respectively. Both Xpert Ultra and Xpert accurately identified all of the 9 rifampicin (RIF)-resistant and 38 RIF-sensitive cases defined by phenotypic DST. Therefore, Xpert Ultra was 100% concordant with phenotypic DST for the detection of RIF resistance. CONCLUSIONS: Xpert Ultra detected significantly more osteoarticular TB cases than Xpert or culture, making it a useful tool for rapid diagnosis of osteoarticular TB.

9.
Luminescence ; 34(6): 595-601, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31074200

RESUMO

In this paper, the interactions of pepsin with fluoroquinolones, including norfloxacin (NFX) or ofloxacin (OFX), were investigated using fluorescence spectroscopy. The effects of NFX or OFX on pepsin showed that the molecular conformation of pepsin and the microenvironment of tryptophan residues were changed under mimicked physiological conditions. Static quenching was suggested as a factor. Quenching constants and binding constants were determined and thermodynamic parameters were calculated at three temperatures (25°C, 31°C and 37°C). Molecular interaction distances (binding distance r) were obtained. Binding was enthalpy driven and the process was spontaneous. Synchronous fluorescence, three-dimensional fluorescence spectroscopy and molecular simulation were used for analysis. Interactions were further tested using molecular modelling. Quenching and binding constants of NFX with pepsin were the highest when testing NFX/OFX/fleroxacin/gatifloxacin with pepsin combinations. NFX was the strongest quencher, and affinity of NFX for pepsin was higher than that of OFX/fleroxacin/gatifloxacin.

10.
Front Immunol ; 10: 561, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30972061

RESUMO

Surfactant protein A (SP-A) plays critical roles in host defense, regulation of inflammation and surfactant metabolism in the lung. The human SP-A locus consists of two functional genes, SFTPA1 and SFTPA2 encoding surfactant proteins SP-A1 and SP-A2, respectively. Structural and functional differences exist between SP-A1 and SP-A2 in vitro and in vivo. Ozone is a major air pollutant with a negative impact on many biological processes. In this study we used humanized transgenic (hTG) SP-A1 and SP-A2 mice, and SP-A KO mice to study in vivo effects of SP-A1 and SP-A2 on the bronchoalveolar lavage (BAL) proteomic profile and associated signaling pathways in response to ozone or filtered air (FA) exposure and Klebsiella pneumoniae infection. The BAL samples were harvested 24 h after ozone (2 ppm for 3 h) or FA exposure and infection and analyzed by two-dimensional difference gel electrophoresis (2D-DIGE) and MALDI-ToF/ToF. We found: that (1) Ozone exposure, but not infection, is a major factor for increases in total BAL protein content. (2) A total of 36 proteins were identified, accounting for 89.62% of the BAL proteins resolved by the 2D-DIGE system. (3) The number of proteins in which levels were altered more than 25% following infection and FA exposure was: SP-A2 > SP-A1 > KO for male mice, and SP-A2 ≈ SP-A1 > KO for female mice. (4) The number of proteins with more than 25% increase/decrease after ozone exposure and infection was: SP-A2 > SP-A1 ≈ KO, with the majority being increases in male mice and decreases in female mice. (5) Eleven out of the 36 proteins, including annexin A5, glutathione S-transferase A4, SP-A1/SP-A2, and 14-3-3 zeta protein, exhibited significant differences among SP-A genotypes. The acute phase response (APR) that includes the NF-kB signaling pathway plays a critical role, followed by Nrf2-mediated oxidative response, and others. These associated with SP-A genotype, sex, and ozone-induced oxidative stress in response to infection. We concluded that human SP-A2 and SP-A1 exhibit differential genotype-and sex-dependent innate immune responses to microbial pathogens and/or ozone-induced oxidative stress by modulating proteomic patterns and signaling pathways in the lung.

11.
Genes (Basel) ; 10(4)2019 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-31010093

RESUMO

Aquaporins (AQPs), which are members of the major intrinsic protein (MIP) family, play an important role in the transport of water and other small, uncharged solutes across membranes. In this study, we identified gene encoding two aquaporin 12-like (AQP12L) proteins, CsAqp12L_v1 and CsAqp12L_v2, from Chilo suppressalis, a serious rice pest in Asia. Phylogenetic analysis indicated that CsAQP12L_V1 and CsAQP12L_V2 were grouped in a well-supported cluster that included other members of Lepidoptera. The two proteins are almost identical, except that CsAQP12L_V1 lacks 34 amino acids that are present in CsAQP12L_V2 at site 217. The qRT-PCR indicated that both CsAqp12L and CsAqp12L_v2 were expressed in heads, epidermis, foregut, midgut, and hindguts, with the highest level of expression in hindguts, heads, and epidermis. Expression of CsAqp12L and CsAqp12L_v2 was detected in all life stages and both sexes and was highest in first instar larvae and lowest in eggs. Expression of CsAqp12L and CsAqp12L_v2 was not significantly altered by exposure to brief changes in temperature. There were no significant differences in the third instar larvae, male and female pupae, and female adults in response to adverse humidity. However, the mRNA level of CsAqp12L in the fifth instar larvae and CsAqp12L_v2 in male adults was induced significantly by low humidity, respectively. Moreover, Xenopus oocytes injected with cRNAs of CsAQP12L_V1 and CsAQP12L_V2 showed no significant changes in permeability to water, glycerol, trehalose, or urea. The two CsAQP12L variants likely localize to an intracellular location in C. suppressalis and may respond to novel stimuli.

12.
J Insect Sci ; 19(2)2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30817822

RESUMO

Serotonin (5-hydroxytryptamine [5-HT]) is a monoamine neurotransmitter that plays an important role in regulating a variety of physiological and behavioral activities. In this study, the 5-HT7 receptor gene was cloned from the ant Polyrhachis vicina Roger (1863). The complete Pv5-HT7 receptor cDNA is 3054 bp, including a 5'-untranslated region (UTR) of 790 bp, a 3'-UTR of 752 bp and an open reading frame of 1512 bp encoding polypeptide of 503 amino acids. Hydrophobic analysis suggests that seven trans-membrane domains are the major sequence characteristic of the Pv5-HT7 receptor. In addition, the Pv5-HT7 receptor has three potential N-glycosylation sites, a palmitoylation site, three protein kinase A phosphorylation sites, and four protein kinase C phosphorylation sites. Phylogenetic analysis revealed that the deduced Pv5-HT7 receptor sequence shared a high homology with 5-HT7 receptor sequences of other species, such as a 78% similarity with the Am5-HT7 receptor (Apis mellifera). Real-time quantitative PCR (qRT-PCR) results showed that the expression level of the Pv5-HT7 receptor was low in the eggs and 1th-4th larval stages, but it was increased in the pupae stage and reached its peak in the adult workers. Western blot results showed that the highest protein expression was in the male body, head, and thorax. These results suggest that the Pv5-HT7 receptor may have specific functions in regulating the development of P. vicina, especially in adult formation and caste differentiation, feeding and caring behaviors of workers in the nest, and in the development of motor organs and mating behaviors in males.


Assuntos
Formigas/genética , Proteínas de Insetos/genética , Receptores de Serotonina/genética , Sequência de Aminoácidos , Animais , Formigas/metabolismo , Sequência de Bases , Clonagem Molecular , Feminino , Perfilação da Expressão Gênica , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Masculino , Óvulo/metabolismo , Filogenia , Pupa/crescimento & desenvolvimento , Pupa/metabolismo , Receptores de Serotonina/metabolismo , Alinhamento de Sequência
13.
J Infect ; 78(4): 311-316, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30796951

RESUMO

OBJECTIVES: We assessed the diagnostic performance of Xpert MTB/RIF Ultra (Xpert Ultra) in comparison to Xpert MTB/RIF (Xpert) for the detection of paucibacillary tuberculosis (TB). METHODS: Smear-negative sputum, pleural fluid and cerebrospinal fluid (CSF) were collected from TB suspects at Beijing Chest Hospital (Beijing, China) and were examined using smear, Xpert and culture. Xpert Ultra was tested using specimens stored at -80 °C. Drug susceptibility testing (DST) was conducted for all of the isolates recovered. The performances of Xpert Ultra and Xpert were evaluated using composite reference standard (CRS) as gold standard, which included clinical, laboratory, histopathological, radiological and follow-up features. RESULTS: Totally 689 cases were included. The direct head-to-head diagnostic performance comparison showed higher sensitivity of Xpert Ultra in contrast with Xpert among 292 smear-negative pulmonary TB (PTB) (70.89% vs 57.88%, P = 0.001), 108 tuberculous pleurisy (61.11% vs 34.26%, P<0.001), and 43 tuberculous meningitis (44.19% vs 18.60%, P = 0.011). The percentage of definite PTB, tuberculous pleurisy and tuberculous meningitis increased from 67.12% to 78.77%, 61.11% to 69.44% and 23.26% to 51.16%, respectively after integrating Xpert Ultra outcomes. The specificity of Xpert Ultra and Xpert was 96.75% (238/246) and 98.37% (242/246), respectively. Xpert Ultra and Xpert performed similarly in detecting rifampicin resistance. CONCLUSION: Xpert Ultra has higher sensitivity but relatively reduced specificity compared with Xpert in diagnosis of paucibacillary TB. Performing Xpert Ultra would improve the definite diagnosis of smear-negative pulmonary tuberculosis, tuberculous pleurisy and tuberculous meningitis.

14.
Pest Manag Sci ; 2018 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-30379402

RESUMO

BACKGROUND: The small brown planthopper (SBPH), Laodelphax striatellus Fallén, is one of the most destructive pests on rice. This pest transmits rice stripe virus (RSV) both horizontally and vertically, leading to major yield and economic losses in rice production. However, the way that RSV particles enter oocytes of SBPH remains largely unknown. Thus, identification of key factors involved in the interaction between SBPH and RSV in the ovary is crucial. RESULTS: Transcriptome of non-viruliferous (NV) or high viruliferous (HV) SBPH ovaries at 24 h and 48 h of emergence was sequenced. Differentially expressed genes analysis showed that vitellogenin receptor (VgR) was significantly high expressed in the ovary of the HV SBPH strains compared to NV strains. qRT-PCR showed that LsVgR was high expressed in ovaries of female adults and maintained a high level of expression at the early stage of ovary development. By using RNA interference (RNAi), the expression of LsVgR in ovary of HV strain was significantly decreased by 98.1%. RSV titer was reduced by 60.9% as quantified by viral RNA3 intergenic region and the transcripts of nucleocapsid protein gene (CP) reduced by 46.3%. The numbers of offspring hatched were significantly reduced in dsRNA-treated groups. The transcripts of CP were not affected by silencing LsVgR, whereas the abundance of RNA dependent RNA Polymerase (RdRp) increased by 15-fold in the member of surviving progenies. CONCLUSION: Our results suggest that vitellogenin receptor participates in regulating RSV replication during oogenesis. This article is protected by copyright. All rights reserved.

15.
Sci Rep ; 8(1): 15393, 2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30337682

RESUMO

Pneumonia and sepsis are major risk factors for acute kidney injury (AKI). Patients with pneumonia and AKI are at increased risk for morbidity and mortality. Surfactant protein D (SP-D) expressed in lung and kidney plays important roles in innate immunity. However, little is known about the role of organ-specific SP-D in the sepsis. The current study uses wild type (WT), SP-D knockout (KO), and humanized SP-D transgenic (hTG, lung-specific SP-D expression) mice to study organ-specific role of SP-D in pneumonia-induced sepsis. Analyses demonstrated differential lung and kidney injury among three-type mice infected with Pseudomonas aeruginosa. After infection, KO mice showed higher injurious scores in both lung and kidney, and decreased renal function than WT and hTG mice. hTG mice exhibited comparable lung injury but more severe kidney injury compared to WT mice. Increased renal tubular apoptosis, NF-κB activation and proinflammatory cytokines in the kidney of KO mice were found when compared with WT and hTG mice. Furthermore, in vitro primary proximal tubular epithelial cells from KO mice showed more apoptosis with higher level of activated caspase-3 than those from WT mice after LPS treatment. Collectively, SP-D attenuates AKI in the sepsis by modulating renal apoptosis, inflammation and NF-κB signaling.

16.
Clin Infect Dis ; 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30321294

RESUMO

Background: The increase in MDR-TB severely hampers TB prevention and control in China, a country with the second highest MDR-TB burden globally. The first nationwide drug-resistant TB surveillance program provides an opportunity to comprehensively investigate the epidemiological/drug-resistance characteristics, potential drug-resistance mutations, and effective population changes of Chinese MDR-TB. Methods: We sequenced 357 MDR strains from 4,600 representative TB-positive sputum samples collected from the survey (70 counties in 31 provinces). Drug-susceptibility testing was performed using 18 anti-tuberculosis drugs, representing the most comprehensive drug-resistance profile to date. We employed three statistical methods and one machine learning method to identify drug-resistance genes/SNPs. Bayesian skyline analysis investigated the changes in effective population size. Results: Epidemiological/drug-resistance characteristics showed different multidrug-resistance profiles, co-resistance patterns, preferred drug combination/use, and recommended regimens among seven Chinese administrative regions. These not only reflected the serious multidrug co-resistance and drug misuse in some regions but these factors were also potentially significant in facilitating the development of appropriate regimens for MDR-TB treatment in China. Further investigation identified 86 drug-resistance genes/intergenic regions/SNPs (58 new), providing potential targets for diagnosis and treatment of MDR-TB. In addition, the effective population of Chinese MDR-TB displayed a strong expansion during 1993-2000, reflecting socioeconomic transition within the country. The phenomenon of expansion was restrained after 2000, likely attributable to the advances in diagnosis/treatment technologies and government support. Conclusions: Our findings provide an important reference and improved understanding of MDR-TB in China, potentially significant in achieving the goal of precision medicine with respect to MDR-TB prevention and treatment.

17.
Nat Commun ; 9(1): 4160, 2018 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-30297884

RESUMO

Being relatively simple and practical, Drosophila transgenic RNAi is the technique of top priority choice to quickly study genes with pleiotropic functions. However, drawbacks have emerged over time, such as high level of false positive and negative results. To overcome these shortcomings and increase efficiency, specificity and versatility, we develop a next generation transgenic RNAi system. With this system, the leaky expression of the basal promoter is significantly reduced, as well as the heterozygous ratio of transgenic RNAi flies. In addition, it has been first achieved to precisely and efficiently modulate highly expressed genes. Furthermore, we increase versatility which can simultaneously knock down multiple genes in one step. A case illustration is provided of how this system can be used to study the synthetic developmental effect of histone acetyltransferases. Finally, we have generated a collection of transgenic RNAi lines for those genes that are highly homologous to human disease genes.

18.
Front Physiol ; 9: 1188, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30214413

RESUMO

Three closely related species, Helicoverpa armigera, H. assulta, and Heliothis virescens from Lepidoptera Noctuidae, are used as a model system for exploring sexual communication and species isolation. Pheromone receptors (PRs) previously discovered in model moth species include seven in H. armigera, six in H. assulta, and six in H. virescens. PRs named OR6, OR13, and OR16 among these species were found to be functional, characterized by an in vitro Xenopus oocytes system. Using an in vivo transgenic fly system, functional assays of OR6, OR13, and OR16 clades from three closely related Noctuidae species showed that OR13 function was highly conserved, whereas OR6 and OR16 exhibited functional divergence. Similar results were produced from assays in the Xenopus oocytes system. Combined with earlier behavioral results and electrophysiological recordings, we found corresponding relationships among pheromones, PRs, and neurons at the periphery sensory system of each species. Our results provide vital information at the neuronal and molecular level, shedding insight into the sexual communication of closely related species in Lepidoptera.

19.
J Insect Physiol ; 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30193842

RESUMO

Chemoreception systems play a crucial role in regulating key behavioral activities of insects, such as mating, oviposition, and foraging. Odorant receptors (ORs) trigger the transduction of chemical signals into electric signals, and are involved in the corresponding responses associated with odorant guidance behaviors. Pheromone receptors (PRs) of male adult insects are generally thought to function in the recognition of female sex pheromones, and are also important molecular targets for the development of behavioral inhibitors and insecticides. In this study, we successfully expressed and functionally analyzed four AlepPRs of Athetis lepigone in Xenopus oocytes using the two-electrode voltage-clamp method. The results demonstrated that AlepOR3 responded exclusively to the sex pheromone compound of A. lepigone, (Z)-7-dodecenyl acetate (Z7-12:Ac) (EC50 = 8.830 × 10-6 M), while AlepOR4 responded to all five compounds [(Z7-12:Ac, (Z)-8-dodecenyl acetate (Z8-12:Ac), (Z)-9-tetradecenyl acetate (Z9-14:Ac), (Z,E)-9,11-tetradecadienyl acetate (Z9,E11-14:Ac), and (Z,E)-9,12-tetradecadienyl acetate (Z9,E12-14:Ac)] and had a higher response to Z9-14:Ac (EC50 = 2.243 × 10-5 M) than to Z7-12:Ac. However, AlepOR6 displayed a significantly higher response to a non-pheromone of A. lepigone, Z9,E12-14:Ac (EC50 = 7.145 × 10-6 M), than to the other four compounds. AlepOR5 displayed no responses to any of the pheromone compounds of A. lepigone, but responded exclusively to (Z)-11-hexadecenyl acetate (Z11-16:Ac) (EC50 = 7.870 × 10-6 M), a sex pheromone compound of other Noctuidae species. These findings can help explore the molecular mechanisms of sex pheromone recognition in A. lepigone and other moths, and develop broad-spectrum behavioral inhibitors and insecticides against different maize moths in future.

20.
Front Microbiol ; 9: 1886, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30177918

RESUMO

Tuberculosis (TB) has surpassed HIV as the leading infectious disease killer worldwide since 2014. The main pathogen, Mycobacterium tuberculosis (Mtb), contains ~4,000 genes that account for ~90% of the genome. However, it is still unclear which of these genes are primary/secondary, which are responsible for generality/individuality, and which interconvert during evolution. Here we utilized a pan-genomic analysis of 36 Mtb genomes to address these questions. We identified 3,679 Mtb core (i.e., primary) genes, determining their phenotypic generality (e.g., virulence, slow growth, dormancy). We also observed 1,122 dispensable and 964 strain-specific secondary genes, reflecting partially shared and lineage-/strain-specific individualities. Among which, five L2 lineage-specific genes might be related to the increased virulence of the L2 lineage. Notably, we discovered 28 Mtb "Super Core Genes" (SCGs: more than a copy in at least 90% strains), which might be of increased importance, and reflected the "super phenotype generality." Most SCGs encode PE/PPE, virulence factors, antigens, and transposases, and have been verified as playing crucial roles in Mtb pathogenicity. Further investigation of the 28 SCGs demonstrated the interconversion among SCGs, single-copy core, dispensable, and strain-specific genes through copy number variations (CNVs) during evolution; different mutations on different copies highlight the delicate adaptive-evolution regulation amongst Mtb lineages. This reflects that the importance of genes varied through CNVs, which might be driven by selective pressure from environment/host-adaptation. In addition, compared with Mycobacterium bovis (Mbo), Mtb possesses 48 specific single core genes that partially reflect the differences between Mtb and Mbo individuality.

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