Publications by authors named "GuiRong Wang"

220 Publications

Antioxidant Activity and Mechanism of Avenanthramides: Double H/e Processes and Role of the Catechol, Guaiacyl, and Carboxyl Groups.

J Agric Food Chem 2021 Jun 22. Epub 2021 Jun 22.

Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, No.209, Tongshan Road, Xuzhou, Jiangsu 221004, China.

Avenanthramides (AVAs), unique phenolic compounds in oats, have attracted increasing interest due to their health benefits. Eight representative AVAs were studied using the density functional theory (DFT) method to elucidate their antioxidant activity and mechanism. Preference of different mechanisms was evaluated based on thermodynamic descriptors involved in double (2H/2e) free radical scavenging reactions. It was found that the hydrogen atom transfer (HAT) mechanism is more favorable in the gas and benzene phases, while sequential proton loss electron transfer (SPLET) is preferred in polar media. The results suggest the feasibility of the double HAT and double SPLET mechanisms for and -series AVAs. The sequential triple proton loss double electron transfer (StPLdET) mechanism represents the dominant pathway in aqueous solution at physiological pH. In addition, the sequential proton loss hydrogen atom transfer (SPLHAT) mechanism provides an alternative pathway to trap free radicals. Results also revealed the important role of the catechol, guaiacyl, and carboxyl moieties.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jafc.1c01591DOI Listing
June 2021

The Comparative Influence of 2 and 4 Weeks Preoperative Antituberculosis Treatment on Spinal Tuberculosis Surgery: A Multicenter, Prospective, Randomized Clinical Trial.

Infect Dis Ther 2021 Jun 13. Epub 2021 Jun 13.

Department of Orthopedics, Beijing Key Laboratory for Drug Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beiguan St #9, Beijing, 101149, China.

Introduction: A trade-off between successful surgery and minimizing the operation delay for patients with spinal tuberculosis (TB) is a major consideration to determine the duration of preoperational anti-TB treatment (AAT). In this study, 2 and 4 weeks preoperative AAT durations were compared for their influence on the operation outcomes.

Method: A multicenter, prospective, randomized trial was conducted in four hospitals in China. New patients with spinal TB were recruited and randomly allocated to two groups (2 or 4 weeks' preoperative treatment) and administered the standardized first-line anti-TB drugs. The symptom changing and indicators reflecting recovery and side effects of the treatment were monitored. Patient was followed up for another 18 months after completion of treatment.

Results: In total, 150 eligible patients were enrolled between June 2014 and December 2016, and 13 patients were excluded after the enrollment. The remaining 137 participants were randomly allocated to the 2-week group (n = 68) or the 4-week group (n = 69). These two groups acquired similar surgical outcomes, considering wound healing rate within 3 months after the operation (94.20%, 65/69 vs 89.71%, 61/68; P = 0.333) and bony fusion rate within 6 months (98.46%, 64/65 vs 95.45%, 63/66; P = 0.317). However, the culture positive rate of pus collected during operation in the 4-week group (41.94%) was significantly lower than that of the 2-week group (60.94%, P = 0.033). No reoccurrence of disease was observed in either group during the 18-month follow-up period.

Conclusion: Patients with spinal TB administered 2 or 4 weeks of preoperative anti-TB treatment acquired similar surgical outcomes. However, patients who underwent the operation sooner suffered 2 weeks less agony from the disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s40121-021-00462-2DOI Listing
June 2021

Functional Characterization of Sex Pheromone Neurons and Receptors in the Armyworm, (Walker).

Front Neuroanat 2021 28;15:673420. Epub 2021 Apr 28.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.

Pheromone receptors (PRs) of moths are expressed on the dendritic membrane of odorant receptor neurons (ORNs) housed in the long trichoid sensilla (TS) of antennae and are essential to sex pheromone reception. The function of peripheral neurons of in recognizing sex pheromones is still unclear. In this study, electroantennogram recordings were performed from male and female antennae of , and showed that the major component of sex pheromones, ()-11-hexadecenal (Z11-16:Ald), evoked the strongest response of male antennae with significant differences between sexes. Single sensillum recording was used to record responses of neurons housed in TS of male . The results revealed four types of TS with three neurons housed in each type, based on profiles of responses to sex pheromone components and pheromone analogs. ORN-B of type-I TS was specifically tuned to the major sex pheromone component Z11-16:Ald; ORN-Bs in type-III and type-IV TSs were, respectively, activated by minor components ()-11-hexadecen-1-yl acetate (Z11-16:OAc) and hexadecenal (16:Ald); and ORNs in type-II TS were mainly activated by the sex pheromone analogs. We further cloned full-length sequences of six putative genes and an gene. Functional characterization of PRs in the oocyte system demonstrated that male antennae-biased MsepPR1 responded strongly to ()-9-tetradecenal (Z9-14:Ald), suggesting that may be expressed in type-II TS. MsepPR6 was exclusively tuned to ()-9-tetradecen-1-yl acetate (Z9-14:OAc). MsepPR2 and MsepPR4 showed no responses to any tested components. Female antennae-biased MespPR5 was broadly tuned to Z9-14:Ald, Z9-14:OAc, Z11-16:Ald, and ()-11-hexadecen-1-ol (Z11-16:OH). Our results further enriched the sex pheromone recognition mechanism in the peripheral nervous system of moth .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnana.2021.673420DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8113758PMC
April 2021

Distinct protocerebral neuropils associated with attractive and aversive female-produced odorants in the male moth brain.

Elife 2021 May 14;10. Epub 2021 May 14.

Chemosensory lab, Department of Psychology, Norwegian University of Science and Technology, Trondheim, Norway.

The pheromone system of heliothine moths is an optimal model for studying principles underlying higher-order olfactory processing. In , three male-specific glomeruli receive input about three female-produced signals, the primary pheromone component, serving as an attractant, and two minor constituents, serving a dual function, that is, attraction versus inhibition of attraction. From the antennal-lobe glomeruli, the information is conveyed to higher olfactory centers, including the lateral protocerebrum, via three main paths - of which the medial tract is the most prominent. In this study, we traced physiologically identified medial-tract projection neurons from each of the three male-specific glomeruli with the aim of mapping their terminal branches in the lateral protocerebrum. Our data suggest that the neurons' widespread projections are organized according to behavioral significance, including a spatial separation of signals representing attraction versus inhibition - however, with a unique capacity of switching behavioral consequence based on the amount of the minor components.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.7554/eLife.65683DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8154038PMC
May 2021

Development and Preliminary Application of Multiplex Loop-Mediated Isothermal Amplification Coupled With Lateral Flow Biosensor for Detection of .

Front Cell Infect Microbiol 2021 27;11:666492. Epub 2021 Apr 27.

Key Laboratory of Major Diseases in Children, Ministry of Education, National Key Discipline of Pediatrics (Capital Medical University), National Clinical Research Center for Respiratory Diseases, Beijing Key Laboratory of Pediatric Respiratory Infection Diseases, Beijing Pediatric Research Institute, Beijing Children's Hospital, Capital Medical University, Beijing, China.

The aim of this study was to develop a simple and reliable method to detect (MTBC) and verify its clinical application preliminarily. A loop-mediated isothermal amplification method coupled with lateral flow biosensor (LAMP-LFB) assay, was developed and evaluated for detection of MTBC. Two sets of primers, which targeted IS and IS sequences of MTBC, were designed for establishment of multiplex LAMP-LFB assay. The amplicons were labelled with biotin and fluorescein isothiocyanate (FITC) by adding FITC labelled primer and biotin-14-dATP and biotin-14-dCTP and could be visualized using LFB. The optimal reaction conditions of multiplex LAMP-LFB assay confirmed were 66°C for 50 min. The analytical sensitivity of multiplex LAMP-LFB is 10 fg of genomic templates using pure culture, and no cross-reactivity with other common bacteria and non-tuberculous mycobacteria strains was obtained. A total of 143 clinical samples collected from 100 TB patients (62 definite TB cases and 38 probable TB cases) and 43 non-TB patients were used for evaluating the feasibility of multiplex LAMP-LFB assay. The multiplex LAMP-LFB (82.0%, 82/100) showed higher sensitivity than culture (47.0%, 47/100, P < 0.001) and Xpert MTB/RIF (54.0%, 54/100, P < 0.001). Importantly, the multiplex LAMP-LFB assay detected additional 28 probable TB cases, which increased the percentage of definite TB cases from 62.0% (62/100) to 90.0% (90/100). The specificity of multiplex LAMP-LFB assay in patients without TB was 97.7% (42/43). Therefore, multiplex LAMP-LFB assay is a simple, reliable, and sensitive method for MTBC detection, especially in probable TB cases and resource limited settings.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fcimb.2021.666492DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8110928PMC
April 2021

Dominant egg surface bacteria of Holotrichia oblita (Coleoptera: Scarabaeidae) inhibit the multiplication of Bacillus thuringiensis and Beauveria bassiana.

Sci Rep 2021 May 4;11(1):9499. Epub 2021 May 4.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.

Holotrichia oblita (Coleoptera: Scarabaeidae) and some other scarab beetles are the main soil-dwelling pests in China. Bacillus thuringiensis (Bt) and Beauveria bassiana (Bb) are entomopathogens that have been used as biocontrol agents of various pests. However, scarab larvae especially H. oblita exhibited strong adaptability to these pathogens. Compared to other scarabs, H. oblita could form a specific soil egg case (SEC) structure surrounding its eggs, and young larvae complete the initial development process inside this structure. In this study, we investigated the role of SEC structure and microorganisms from SEC and egg surface in pathogen adaptability. 16S rRNA gene analysis revealed low bacterial richness and high community unevenness in egg surface, with Proteobacteria, Firmicutes, Bacteroidetes and Fusobacteria dominating. In terms of OTUs composition analysis, the data show that the egg surface contains a large number of unique bacteria, indicating that the egg bacterial community may be derived from maternal transmission. Furthermore, we found that all culturable bacteria isolated from egg surface possessed antimicrobial activity against both Bt and Bb. The Pseudomonas bacteria with a significantly higher abundance in egg surface showed strong Bt- and Bb antagonistic ability. In conclusion, this study demonstrated a unique and antimicrobial bacterial community of H. oblita egg surface, which may contribute to its adaptability. Furthermore, the specific SEC structure surrounding the H. oblita eggs will provide a stable microenvironment for the eggs and egg surface bacteria, which probably provides more advantages for H. oblita adaptation ability.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-89009-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8096819PMC
May 2021

Sex peptide receptor mediates the post-mating switch in Helicoverpa armigera (Lepidoptera: Noctuidae) female reproductive behavior.

Pest Manag Sci 2021 Jul 19;77(7):3427-3435. Epub 2021 Apr 19.

Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China.

Background: In Drosophila, the sex peptide receptor (SPR) in females to detect male sex peptide (SP) and trigger changes in female behavior including mating rejection and oviposition. In moths, the SPR had been identified and investigated the limited function by using RNA interference (RNAi). However, the detailed function of SPR after a normal mating in moths, especially the role in female sexual receptivity, remains to be elucidated.

Results: In this study, we use Helicoverpa armigera, an economically important pest worldwide, as a case study to verify the function of SPR in vivo by CRISPR/Cas9 gene editing system. Analyzing the post-mating behaviors in mutant females, we investigated that HarmSPR could mediate the long-term sexual receptivity (remating, sex pheromone production and calling behavior) switch in female, but not affect the short-term sexual receptivity and the duration time of remating. The oviposition of mated HarmSPR females was significantly decreased by ~70% comparing to wild-type (WT) mated females and there were more eggs staying in the ovary of mutant females. SPR also showed effect on female longevity, which is that the mated HarmSPR females showed longer longevity than mated WT females.

Conclusion: The results detailedly demonstrated the functional role of SPR in female post-mating behaviors and we could propose a pest control strategy in which developing an antagonist of SPR to reduce the oviposition of female. © 2021 Society of Chemical Industry.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/ps.6391DOI Listing
July 2021

High-efficiency and multiplex adenine base editing in plants using new TadA variants.

Mol Plant 2021 May 22;14(5):722-731. Epub 2021 Feb 22.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China; Scientific Observing and Experimental Station of Crop Pests in Guilin, Ministry of Agriculture and Rural Affairs, Guilin 541399, China. Electronic address:

Recently reported adenine base editors (ABEs) exhibit powerful potential for targeted gene correction as well as developing gain-of-function mutants and novel germplasms for both gene function studies and crop breeding. However, editing efficiency varies significantly among different target sites. Here, we investigated the activities of three evolved E. coli adenosine deaminase TadA variants (TadA8e, TadA8.17, and TadA8.20) side-by-side in transgenic rice. We found that TadA8e outperforms TadA8.17 and TadA8.20, and induces efficient A-to-G conversion at all tested sites in the rice genome, including those that were uneditable by ABE7.10 in our previous experiments. Furthermore, V82S/Q154R mutations were incorporated into TadA8e, resulting in a new variant that we named TadA9. Our data show that TadA9 is broadly compatible with CRISPR/SpCas9, CRISPR/SpCas9-NG, and CRISPR/SpRY, as well as CRISPR/ScCas9 nickase systems, achieving comparable or enhanced editing in a larger editing window at diverse PAM sites as compared with TadA8e. Finally, TadA9 was used to simultaneously install novel SNPs in four endogenous herbicide target genes in the commercial rice cultivar Nangeng 46 for potential field application in weed control. Collectively, we successfully generated a series of novel ABEs that can efficiently edit adenosines in the rice genome. Our findings suggest that TadA9 and TadA8e have great potentials in the development of plant base editors and crop molecular breeding.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.molp.2021.02.007DOI Listing
May 2021

Fidaxomicin has high activity against .

J Med Microbiol 2021 Mar 17;70(3). Epub 2021 Feb 17.

National Clinical Laboratory on Tuberculosis, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing Chest Hospital, Capital Medical University, Beijing, PR China.

This study aimed to evaluate whether the antibiotic fidaxomicin has activity against (Mtb). 38 fully drug-sensitive Mtb strains and 34 multidrug-resistant tuberculosis (MDR-TB) strains were tested using the microplate alamar blue assay (MABA) method to determine the minimum inhibitory concentrations (MICs) for fidaxomicin and rifampicin. Fidaxomicin has high activity against Mtb and is a potential drug to treat Mtb, and MDR-TB infections in particular.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1099/jmm.0.001324DOI Listing
March 2021

Immunogenicity Assessment of Different Segments and Domains of Group a Streptococcal C5a Peptidase and Their Application Potential as Carrier Protein for Glycoconjugate Vaccine Development.

Vaccines (Basel) 2021 Feb 9;9(2). Epub 2021 Feb 9.

National Glycoengineering Research Center and Shandong Key Laboratory of Carbohydrate Chemistry and Glycobiology, Shandong University, 72 Binhai Road, Qingdao 266237, China.

Group A streptococcal C5a peptidase (ScpA) is a highly conserved surface virulence factor present on group A streptococcus (GAS) cell surfaces. It has attracted much more attention as a promising antigenic target for GAS vaccine development due to its high antigenicity to stimulate specific and immunoprotective antibodies. In this study, a series of segments of ScpA were rationally designed according to the functional domains described in its crystal structure, efficiently prepared and immunologically evaluated so as to assess their potential as antigens for the development of subunit vaccines. Immunological studies revealed that Fn, Fn2, and rsScpA193 proteins were promising antigen candidates worthy for further exploration. In addition, the potential of Fn and Fn2 as carrier proteins to formulate effective glycoconjugate vaccine was also investigated.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/vaccines9020139DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7915350PMC
February 2021

Identification and Functional Characterization of Two Putative Pheromone Receptors in the Potato Tuber Moth, .

Front Physiol 2020 25;11:618983. Epub 2021 Jan 25.

State Key Laboratory for Biology of Plant Disease and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.

Pheromones are a kind of signal produced by an animal that evoke innate responses in conspecifics. In moth, pheromone components can be detected by specialized olfactory receptor neurons (OSNs) housed in long sensilla trichoids on the male antennae. The pheromone receptors (PRs) located in the dendrite membrane of OSNs are responsible for pheromone sensing in most Lepidopteran insects. The potato tuber moth is a destructive pest of Solanaceae crops. Although sex attractant is widely used in fields to monitor the population of , no study has been reported on the mechanism the male moth of uses to recognize sex pheromone components. In the present study, we cloned two pheromone receptor genes and in . The transcripts of them were highly accumulated in the antennae of male adults. Functional analysis using the heterologous expression system of oocyte demonstrated that these two PR proteins both responded to (, )-4,7-13: OAc and (, , )-4,7,10-13: OAc, the key sex pheromone components of , whilst they responded differentially to these two ligands. Our findings for the first time characterized the function of pheromone receptors in gelechiid moth and could promote the olfactory based pest management of in the field.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fphys.2020.618983DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7868389PMC
January 2021

Role of Surfactant Protein D in Experimental Otitis Media.

J Innate Immun 2021 Feb 8:1-14. Epub 2021 Feb 8.

Department of Surgery, SUNY Upstate Medical University, Syracuse, New York, USA,

Surfactant protein D (SP-D) is a C-type collectin and plays an important role in innate immunity and homeostasis in the lung. This study studied SP-D role in the nontypeable Haemophilus influenzae (NTHi)-induced otitis media (OM) mouse model. Wild-type C57BL/6 (WT) and SP-D knockout (KO) mice were used in this study. Mice were injected in the middle ear (ME) with 5 μL of NTHi bacterial solution (3.5 × 105 CFU/ear) or with the same volume of sterile saline (control). Mice were sacrificed at 3 time points, days 1, 3, and 7, after treatment. We found SP-D expression in the Eustachian tube (ET) and ME mucosa of WT mice but not in SP-D KO mice. After infection, SP-D KO mice showed more intense inflammatory changes evidenced by the increased mucosal thickness and inflammatory cell infiltration in the ME and ET compared to WT mice (p < 0.05). Increased bacterial colony-forming units and cytokine (IL-6 and IL-1β) levels in the ear washing fluid of infected SP-D KO mice were compared to infected WT mice. Molecular analysis revealed higher levels of NF-κB and NLRP3 activation in infected SP-D KO compared to WT mice (p < 0.05). In vitro studies demonstrated that SP-D significantly induced NTHi bacterial aggregation and enhanced bacterial phagocytosis by macrophages (p < 0.05). Furthermore, human ME epithelial cells showed a dose-dependent increased expression of NLRP3 and SP-D proteins after LPS treatment. We conclude that SP-D plays a critical role in innate immunity and disease resolution through enhancing host defense and regulating inflammatory NF-κB and NLRP3 activation in experimental OM mice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1159/000513605DOI Listing
February 2021

Prevalence and molecular characterizations of seven additional drug resistance among multidrug-resistant tuberculosis in China: A subsequent study of a national survey.

J Infect 2021 03 5;82(3):371-377. Epub 2021 Feb 5.

National Tuberculosis Clinical Laboratory, Beijing Key laboratory for Drug-resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beiguan St #9, Beijing 101149, China. Electronic address:

The drug resistance prevalence data facilitates selection of the initial drug for treating multidrug-resistant tuberculosis (MDR-TB). The aim of this study was to investigate the prevalence and molecular characterization of seven additional types of drug resistances among MDR-TB isolates collected from the first/only nationwide drug resistance surveillance in China. A total of 391 out of the 401 MDR-TB strains were successfully recovered by Löwenstein-Jensen medium. Drug susceptibility testing was performed against moxifloxacin (Mfx), bedaquiline (Bdq), linezolid (Lzd), clofazimine (Cfz), cycloserine (Cs), delamanid (Dlm) and pyrazinamide (PZA). The strains were subjected to whole-genome sequencing for the analysis corresponding drug resistant genes and their profiles. 269 (68.80%) were simple MDR-TB, 28 (7.16%) were extensively drug-resistant tuberculosis (XDR-TB) and 94 (24.04%) were pre-XDR-TB. Dlm, Lzd, Cfz and Bdq presented the lowest drug resistant rates i.e. 3.32% (13/391), 3.84% (15/391),6.65% (26/391) and 7.16% (28/391), respectively. Mfx (17.39%, 68/391) and CS (13.55%, 53/391) also demonstrated strong potencies against the MDR strains, whereas PZA (38.36%, 150/391) presented much higher resistant rate. 54.41% (37/68) Mfx-resistant strains carried mutations located within gyrA or gyrB. 70.15% (94/134) PZA-resistant strains had pncA mutations. Two of the 26 Cfz-resistant isolates had mutation in Rv0678 were also resistant to Bdq. Dlm, Lzd, Cfz and Bdq exhibited excellent activity against MDR-TB, including XDR-TB. These data highlighted the necessity of a timely, feasible and reliable DST, while genotypic DST for Mfx and PZA is promising at this moment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jinf.2021.02.004DOI Listing
March 2021

The Value of the Mutation Detection in Predicting Ethionamide Resistance Using Melting Curve Technology.

Infect Drug Resist 2021 29;14:329-334. Epub 2021 Jan 29.

Department of Tuberculosis, Beijing Chest Hospital, Capital Medical University, Beijing 101149, People's Republic of China.

Objective: This study aims to analyze the correlation between gene mutations by melting curve technology and phenotypic drug susceptibility (DST) results of ethionamide (ETH), and evaluate whether gene mutations detection can serve as a molecular marker in predicting ETH resistance.

Methods: A retrospective analysis was conducted on 382 strains of (MTB) with the anti-tuberculosis drugs isoniazid (INH), rifampicin (RIF), ETH, and others. Phenotypic drug susceptibility and the results of and katG genotypes (mutation and no mutation) were obtained using the melting curve technology MeltPro TB assay.

Results: Of the 382 clinical strains of MTB tested, 118 (30.9%) were resistant to INH, and 28 (7.3%) were resistant to ETH. Among the 28 phenotypically ETH-resistant strains, mutations accounted for 42.9% (12/28). These ETH-resistant strains comprise 35.3% (12/34) of the 34 mutant strains. Of 8 single mutation strains (without or mutation), 4(50%) were resistant to INH; however, all of these 8 strains were sensitive to ETH.

Conclusion: The mutation test may not be a reliable predictor of ETH resistance. Mutant strains are not necessarily resistant to ETH. The strains with single inhA mutation (without or mutation) may be effective for ETH treatment. The use of ETH in clinical medicine should be guided by gene (other than alone) detection and phenotypic drug susceptibility testing.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2147/IDR.S268799DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7856099PMC
January 2021

Diagnostic accuracy of Xpert MTB/RIF Ultra for tuberculous meningitis in a clinical practice setting of China.

Diagn Microbiol Infect Dis 2021 May 6;100(1):115306. Epub 2021 Jan 6.

Clinical Center on Tuberculosis Control, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, China. Electronic address:

A comparative performance evaluation of the novel Xpert MTB/RIF Ultra (Xpert Ultra) and MTB/RIF Xpert (Xpert) for tuberculous meningitis (TBM) diagnosis was performed. The cerebrospinal fluids of suspected TBM patients were collected consecutively and subjected to smear microscopy, culture, Xpert, and Xpert Ultra. In total, 160 patients were recruited. Xpert Ultra produced a higher sensitivity (45%, 34 of 76) than Xpert (28%, 21 of 76; P = 0.001) and culture (18%, 14 of 76; P < 0.001), respectively. Inclusion of Xpert Ultra outcomes increased the percentage of definite TBM case from 36% (27 of 76) to 51% (39 of 76). Both Xpert Ultra and Xpert accurately identified the one rifampicin (RIF)-resistant and the 5 RIF-sensitive cases defined by phenotypic drug sensitivity test. The specificities of all of the culture, Xpert and Xpert Ultra were 100% (45 of 45). Xpert Ultra outperformed both Xpert and culture for TBM diagnosis, which may speed up the appropriate treatment of patients in clinical practice.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.diagmicrobio.2020.115306DOI Listing
May 2021

Novel copolymers drive differentiation of human adipose derived stem cells towards chondrocytes and osteoblasts identified by high-throughput approach.

Biomed Phys Eng Express 2020 02 17;6(2):025005. Epub 2020 Feb 17.

Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials, School of Materials Science and Engineering, Changzhou University, Changzhou 213164, People's Republic of China.

Human adipose derived stem cells (hASCs) were seeded onto polymer microarrays that had been fabricated using a variety of acrylate monomers to discover novel substrates that induced differentiation towards chondrocytes and osteoblasts. Flow cytometric analysis showed that both CD105 and CD49d positive hASCs increased rapidly with passage number on the lead polymers, while quantitative PCR analysis showed that the substrate synthesized from methacryloxyethyltrimethyl ammonium chloride, N,N-diethylaminoethyl methacrylate and cyclohexyl methacrylate enhanced chondrogenesis and osteogenensis some 4 and 25 times respectively in terms of the expression of SOX9 and ALP in differentiated stem cells. These copolymers substrates thus have great potential for application in the purification, generation and expansion of defined hASC's and the controlled differentiation of of cells for possible clinical application.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1088/2057-1976/ab7155DOI Listing
February 2020

Response.

Chest 2021 01;159(1):448-449

Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, China. Electronic address:

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chest.2020.08.2071DOI Listing
January 2021

SpRY greatly expands the genome editing scope in rice with highly flexible PAM recognition.

Genome Biol 2021 Jan 4;22(1). Epub 2021 Jan 4.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.

Background: Plant genome engineering mediated by various CRISPR-based tools requires specific protospacer adjacent motifs (PAMs), such as the well-performed NGG, NG, and NNG, to initiate target recognition, which notably restricts the editable range of the plant genome.

Results: In this study, we thoroughly investigate the nuclease activity and the PAM preference of two structurally engineered SpCas9 variants, SpG and SpRY, in transgenic rice. Our study shows that SpG nuclease favors NGD PAMs, albeit less efficiently than the previously described SpCas9-NG, and that SpRY nuclease achieves efficient editing across a wide range of genomic loci, exhibiting a preference of NGD as well as NAN PAMs. Furthermore, SpRY-fused cytidine deaminase hAID*Δ and adenosine deaminase TadA8e are generated, respectively. These constructs efficiently induce C-to-T and A-to-G conversions in the target genes toward various non-canonical PAMs, including non-G PAMs. Remarkably, high-frequency self-editing events (indels and DNA fragments deletion) in the integrated T-DNA fragments as a result of the nuclease activity of SpRY are observed, whereas the self-editing of SpRY nickase-mediated base editor is quite low in transgenic rice lines.

Conclusions: The broad PAM compatibility of SpRY greatly expands the targeting scope of CRISPR-based tools in plant genome engineering.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s13059-020-02231-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7780387PMC
January 2021

Odorant Receptors for Detecting Flowering Plant Cues Are Functionally Conserved across Moths and Butterflies.

Mol Biol Evol 2021 04;38(4):1413-1427

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.

Odorant receptors (ORs) are essential for plant-insect interactions. However, despite the global impacts of Lepidoptera (moths and butterflies) as major herbivores and pollinators, little functional data are available about Lepidoptera ORs involved in plant-volatile detection. Here, we initially characterized the plant-volatile-sensing function(s) of 44 ORs from the cotton bollworm Helicoverpa armigera, and subsequently conducted a large-scale comparative analysis that establishes how most orthologous ORs have functionally diverged among closely related species whereas some rare ORs are functionally conserved. Specifically, our systematic analysis of H. armigera ORs cataloged the wide functional scope of the H. armigera OR repertoire, and also showed that HarmOR42 and its Spodoptera littoralis ortholog are functionally conserved. Pursuing this, we characterized the HarmOR42-orthologous ORs from 11 species across the Glossata suborder and confirmed the HarmOR42 orthologs form a unique OR lineage that has undergone strong purifying selection in Glossata species and whose members are tuned with strong specificity to phenylacetaldehyde, a floral scent component common to most angiosperms. In vivo studies via HarmOR42 knockout support that HarmOR42-related ORs are essential for host-detection by sensing phenylacetaldehyde. Our work also supports that these ORs coevolved with the tube-like proboscis, and has maintained functional stability throughout the long-term coexistence of Lepidoptera with angiosperms. Thus, beyond providing a rich empirical resource for delineating the precise functions of H. armigera ORs, our results enable a comparative analysis of insect ORs that have apparently facilitated and currently sustain the intimate adaptations and ecological interactions among nectar feeding insects and flowering plants.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/molbev/msaa300DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8042770PMC
April 2021

Genomics- and Peptidomics-Based Discovery of Conserved and Novel Neuropeptides in the American Cockroach.

J Proteome Res 2021 02 9;20(2):1217-1228. Epub 2020 Nov 9.

Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou 510631, China.

As a model hemimetabolous insect species and an invasive urban pest that is globally distributed, the American cockroach, , is of great interest in both basic and applied research. Previous studies on neuropeptide identification have been based on biochemical isolation and molecular cloning. In the present study, an integrated approach of genomics- and peptidomics-based discovery was performed for neuropeptide identification in this insect species. First, 67 conserved neuropeptide or neurohormone precursor genes were predicted via an analysis of the genome and transcriptome. Using a large-scale peptidomic analysis of peptide extracts from four different tissues (the central nervous system, corpora cardiac and corpora allata complex, midgut, and male accessory gland), 35 conserved (predicted) neuropeptides and a potential (novel) neuropeptide were then identified. Subsequent experiments revealed the tissue distribution, sex difference, and developmental patterns of two conserved neuropeptides (allatostatin B and short neuropeptide F) and a novel neuropeptide (PaOGS36577). Our study shows a comprehensive neuropeptidome and detailed spatiotemporal distribution patterns, providing a solid basis for future functional studies of neuropeptides in the American cockroach (data are available via ProteomeXchange with identifier PXD021660).
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acs.jproteome.0c00596DOI Listing
February 2021

Overexpression of the homoterpene synthase gene, OsCYP92C21, increases emissions of volatiles mediating tritrophic interactions in rice.

Plant Cell Environ 2021 03 29;44(3):948-963. Epub 2020 Dec 29.

National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research, Huazhong Agricultural University, Wuhan, China.

Plant defence homoterpenes can be used to attract pest natural enemies. However, the biosynthetic pathway of homoterpenes is still unknown in rice, and the practical application of such indirect defence systems suffers from inherent limitations due to their low emissions from plants. Here, we demonstrated that the protein OsCYP92C21 is responsible for homoterpene biosynthesis in rice. We also revealed that the ability of rice to produce homoterpenes is dependent on the subcellular precursor pools. By increasing the precursor pools through specifically subcellular targeting expression, genetic transformation and genetic introgression, we significantly enhanced homoterpene biosynthesis in rice. The final introgressed GM rice plants exhibited higher homoterpene emissions than the wild type rice and the highest homoterpene emission reported so far for such GM plants even without the induction of herbivore attack. As a result, these GM rice plants demonstrated strong attractiveness to the parasitic wasp Cotesia chilonis. This study discovered the homoterpene biosynthesis pathway in rice, and lays the foundation for the utilisation of plant indirect defence mechanism in the "push-pull" strategy of integrated pest management through increasing precursor pools in the subcellular compartments and overexpressing homoterpene synthase by genetic transformation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/pce.13924DOI Listing
March 2021

Insulin/IGF signaling and TORC1 promote vitellogenesis via inducing juvenile hormone biosynthesis in the American cockroach.

Development 2020 10 23;147(20). Epub 2020 Oct 23.

Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology and School of Life Sciences, South China Normal University, Guangzhou 510631, China

Vitellogenesis, including vitellogenin (Vg) production in the fat body and Vg uptake by maturing oocytes, is of great importance for the successful reproduction of adult females. The endocrinal and nutritional regulation of vitellogenesis differs distinctly in insects. Here, the complex crosstalk between juvenile hormone (JH) and the two nutrient sensors insulin/IGF signaling (IIS) and target of rapamycin complex1 (TORC1), was investigated to elucidate the molecular mechanisms of vitellogenesis regulation in the American cockroach, Our data showed that a block of JH biosynthesis or JH action arrested vitellogenesis, in part by inhibiting the expression of (), a key transcription factor gene involved in the sex determination cascade. Depletion of IIS or TORC1 blocked both JH biosynthesis and vitellogenesis. Importantly, the JH analog methoprene, but not bovine insulin (to restore IIS) and amino acids (to restore TORC1 activity), restored vitellogenesis in the neck-ligated (IIS-, TORC1- and JH-deficient) and rapamycin-treated (TORC1- and JH-deficient) cockroaches. Combining classic physiology with modern molecular techniques, we have demonstrated that IIS and TORC1 promote vitellogenesis, mainly via inducing JH biosynthesis in the American cockroach.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1242/dev.188805DOI Listing
October 2020

Essential role for SNMP1 in detection of sex pheromones in Helicoverpa armigera.

Insect Biochem Mol Biol 2020 12 10;127:103485. Epub 2020 Oct 10.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, China; Shenzhen Branch, Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, 518120, China. Electronic address:

The sensory neuron membrane protein, SNMP1, was initially discovered in moths and is associated with sex pheromone sensitive neurons, suggesting a role in the detection of these semiochemicals. Although DrosophilaSNMP1 has been reported to be involved in detecting of the sex pheromone cis-vaccenyl acetate (cVA), the role of this protein in moths in vivo is still largely unexplored. In this study we developed a SNMP1 homozygous mutant line of Helicoverpa armigera using CRISPR/Cas9. Wind-tunnel behavioral experiments showed that HarmSNMP1 males could not be attracted by sex pheromones (Z11-16:Ald/Z9-16:Ald = 97/3), while mating behavior obvervations revealed that the SNMP1 mutant males didn't react much to calling females and the rate of copulation was significantly decreased. The electrophysiological results indicated that HarmSNMP1 contributes to the detection of 16-carbon liner sex pheromones, (Z)-11-hexadecenal (Z11-16:Ald), (Z)-9-hexadecenal (Z9-16:Ald), (Z)-11-hexadecanol (Z11-16:OH) and 16-carbon acetate (Z)-11-hexadecenyl acetate (Z11-16:OAc), but is not required for detecting the 14-carbon sex pheromone component (Z)-9-tetradecenal (Z9-14:Ald) an analogue of Z11-16:Ald, (Z)-9-tetradecen-1-yl formate (Z9-14:OFor), which can activate the Z11-16:Ald-responsive neuron. Taken together, our studies indicated that HarmSNMP1 has an important role in the detection of long-chain sex pheromones, but is not essential for detecting shorter chain sex pheromone in vivo.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ibmb.2020.103485DOI Listing
December 2020

Apolygus lucorum genome provides insights into omnivorousness and mesophyll feeding.

Mol Ecol Resour 2021 Jan 2;21(1):287-300. Epub 2020 Oct 2.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.

Apolygus lucorum (Miridae) is an omnivorous pest that occurs worldwide and is notorious for the serious damage it causes to various crops and substantial economic losses. Although some studies have examined the biological characteristics of the mirid bug, no reference genome is available in Miridae, limiting in-depth studies of this pest. Here, we present a chromosome-scale reference genome of A. lucorum, the first sequenced Miridae species. The assembled genome size was 1.02 Gb with a contig N50 of 785 kb. With Hi-C scaffolding, 1,016 Mb contig sequences were clustered, ordered and assembled into 17 large scaffolds with scaffold N50 length 68 Mb, each corresponding to a natural chromosome. Numerous transposable elements occur in this genome and contribute to the large genome size. Expansions of genes associated with omnivorousness and mesophyll feeding such as those related to digestion, chemosensory perception, and detoxification were observed in A. lucorum, suggesting that gene expansion contributed to its strong environmental adaptability and severe harm to crops. We clarified that a salivary enzyme polygalacturonase is unique in mirid bugs and has significantly expanded in A. lucorum, which may contribute to leaf damage from this pest. The reference genome of A. lucorum not only facilitates biological studies of Hemiptera as well as an understanding of the damage mechanism of mesophyll feeding, but also provides a basis on which to develop efficient control technologies for mirid bugs.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/1755-0998.13253DOI Listing
January 2021

Coordinating Adsorption and Catalytic Activity of Polysulfide on Hierarchical Integrated Electrodes for High-Performance Flexible Li-S Batteries.

ACS Appl Mater Interfaces 2020 Nov 21;12(44):49519-49529. Epub 2020 Oct 21.

State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029, P. R. China.

Lithium-sulfur (Li-S) batteries have been known to be a promising substitute because of their much higher theoretical energy density than that of traditional Li-ion batteries. However, the low utilization of sulfur caused by the poor conductivity of sulfur and shuttle of lithium polysulfides (LiPSs) severely restrict the commercial application of Li-S batteries, especially in flexible wearable devices. Herein, a hierarchical nitrogen-doped carbon nanotube (NCNT)@Co-CoO nanowire array (NWA)-integrated electrode was developed based on the rational design of density functional theory calculations, which shows simultaneous confinement adsorption and catalysis conversion of LiPSs. Raman spectra further proved that the [email protected] NWAs exhibit sufficient adsorption capacity and high catalytic conversion of LiPSs. As a result, the [email protected]@S electrode exhibited the desirable specific capacity and excellent cyclic stability at both low and high sulfur loadings. Moreover, pouch cells with the [email protected]@S cathode show higher capacity under flat or bending states and longer cycle stability than that of the reported results. This work provides a new approach for the development of high-performance Li-S batteries toward future wearable electronics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1021/acsami.0c10453DOI Listing
November 2020

Impact of Ozone, Sex, and Gonadal Hormones on Bronchoalveolar Lavage Characteristics and Survival in SP-A KO Mice Infected with .

Microorganisms 2020 Sep 4;8(9). Epub 2020 Sep 4.

The Center for Host Defense, Inflammation, and Lung Disease (CHILD) Research, Department of Pediatrics, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA.

Surfactant protein A (SP-A) plays an important role in innate immunity. The sex-dependent survival of infected SP-A knockout (KO) mice has been observed. Our goal was to study the impact of ozone (O) and sex, as well as gonadal hormones, on the bronchoalveolar lavage (BAL) readouts and survival, respectively, of infected SP-A KO mice. Male and female SP-A KO mice were exposed to O or filtered air and infected with . We studied markers of inflammation and tissue damage at 4, 24, and 48 h, as well as the survival over 14 days, of gonadectomized (Gx) mice implanted with control pellets (CoP) or hormone (5α-dihydrotestosterone (DHT) in female gonadectomized mice (GxF) or 17β-estradiol (E) in male gonadectomized mice (GxM)). We observed: (1) an increase in neutrophil and macrophage inflammatory protein-2 levels as time progressed post-infection, and O exposure appeared to increase this response; (2) an increase in lactate dehydrogenase, total protein, oxidized protein, and phospholipids in response to O with no consistent sex differences in studied parameters; and (3) a reduction in survival of the GxM and CoP mice, the GxM and E mice, and the GxF and DHT mice but not for the GxF and CoP mice after O. Without SP-A, (a) sex was found to have a minimal impact on BAL cellular composition and tissue damage markers, and (b) the impact of gonadal hormones on survival was found to involve different mechanisms than in the presence of SP-A.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/microorganisms8091354DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7563396PMC
September 2020

Chemically modified curcumin (CMC2.24) alleviates osteoarthritis progression by restoring cartilage homeostasis and inhibiting chondrocyte apoptosis via the NF-κB/HIF-2α axis.

J Mol Med (Berl) 2020 10 28;98(10):1479-1491. Epub 2020 Aug 28.

Department of Orthopedics, Central Laboratory, Renmin Hospital of Wuhan University, Wuhan, 430060, China.

The disorders of cartilage homeostasis and chondrocyte apoptosis are major events in the pathogenesis of osteoarthritis (OA). Herein, we aim to assess the chondroprotective effect and underlying mechanisms of a novel chemically modified curcumin, CMC2.24, in modulating extracellular matrix (ECM) homeostasis and inhibiting chondrocyte apoptosis. Rats underwent the anterior cruciate ligament transection, and medial menisci resection was treated by intra-articular injection with CMC2.24. In an in vitro study, rat chondrocytes were pretreated with CMC2.24 before stimulation with sodium nitroprusside (SNP). Results from in vivo studies demonstrated that the intra-articular administration of CMC2.24 ameliorated osteoarthritic cartilage destruction by promoting collagen 2a1 production and inhibited cartilage degradation and apoptosis by suppressing hypoxia-inducible factor-2a (Hif-2α), matrix metalloproteinase-3, runt-related transcription factor 2, cleaved caspase-3, and vascular endothelial growth factor and the phosphorylation of IκBα and NF-κB p65. The in vitro results revealed that CMC2.24 exhibited a strong inhibitory effect on SNP-induced chondrocyte catabolism and apoptosis. The SNP-enhanced expression of Hif-2α, a catabolic and apoptotic factor, decreased in a dose-dependent manner after CMC2.24 treatment. CMC2.24 pretreatment effectively inhibited SNP-induced IκBα and NF-κB p65 phosphorylation in rat chondrocytes, whereas pretreatment with the NF-κB antagonist BMS-345541 significantly enhanced the effects of CMC2.24. Overall, these results demonstrated that CMC2.24 attenuates OA progression by modulating ECM homeostasis and chondrocyte apoptosis by suppressing the NF-κB/Hif-2α axis, thus providing a new perspective for therapeutic strategies in OA. KEY MESSAGES: • Intra-articular injection of CMC2.24 ameliorated osteoarthritic cartilage destruction. • CMC2.24 promoted cell viability and decreased SNP-induced apoptotic gene expression. • SNP-induced activation of Hif-2α is inhibited by CMC2.24. • CMC2.24 inhibits NF-κB/Hif-2α axis activation to modulate ECM homeostasis and inhibit chondrocyte apoptosis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00109-020-01972-1DOI Listing
October 2020

Antioxidant activity and mechanism of dihydrochalcone C-glycosides: Effects of C-glycosylation and hydroxyl groups.

Phytochemistry 2020 Nov 21;179:112393. Epub 2020 Aug 21.

Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, School of Pharmacy, Xuzhou Medical University, No.209, Tongshan Road, Xuzhou, Jiangsu 221004, China. Electronic address:

Dihydrochalcones (DHCs), an important subgroup of flavonoids, have recently received much attention due to their diverse biological activities. In contrast to their O-glycosides, understanding of the antioxidant property and mechanism of DHC C-glycosides remains limited. Herein, the free radical scavenging activity and mechanism of two representative C-glycosyl DHCs, aspalathin (ASP) and nothofagin (NOT) as well as their aglycones, 3-hydroxyphloretin (HPHL) and phloretin (PHL) were evaluated using the density functional theory (DFT) calculations. The results revealed the crucial role of sugar moiety on the conformation and the activity. The o-dihydroxyl in the B-ring and the 2',6'-dihydroxyacetophenone moiety were found significant in determining the activity. Our results showed that hydrogen atom transfer (HAT) is the dominant mechanism for radical-trapping in the gas and benzene phases, while the sequential proton loss electron transfer (SPLET) is more preferable in the polar environments. Also, the results revealed the feasibility of the double HAT and double SPLET as well as the SPLHAT mechanisms, which provide alternative pathways to trap radical for the studied DHCs. These results could deepen the understanding of the antiradical activity and mechanism of DHCs, which will facilitate the design of novel efficient antioxidants.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.phytochem.2020.112393DOI Listing
November 2020

Effect of OBPs on the response of olfactory receptors.

Methods Enzymol 2020 22;642:279-300. Epub 2020 May 22.

State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China; Guangdong Laboratory of Lingnan Modern Agriculture, Shenzhen, China; Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen, China. Electronic address:

The technique of two-electrode voltage-clamp (TEVC) recording from the heterologous expression system of olfactory receptors (ORs) in Xenopus laevis oocytes has been widely used to deorphanize insect ORs, that is to identify specific ligands for each of them. However, there is a controversial issue on whether ORs are activated by the odorant/OBP complex or the odorant alone. The mechanism of interaction among odorants, odorant-binding proteins (OBPs) and ORs remains largely unknown, due to the limitations in the use of scientific and innovative methods. In this chapter, the modified Xenopus oocytes expression system combined with TEVC technique is used to approach this issue. We describe the experimental strategies and provide detailed protocols for recording the signals generated by ORs in response to odorant/OBP complex at different concentrations. Results obtained by this approach have revealed that the presence of OBPs in the system affects the selectivity and sensitivity responses of ORs. Such studies help understanding the molecular mechanism of odorant detection in peripheral nervous system.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/bs.mie.2020.04.065DOI Listing
May 2020

Response.

Chest 2020 08;158(2):830-831

Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Institute, Beijing, China. Electronic address:

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chest.2020.04.022DOI Listing
August 2020