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Screening and identification of bioactive compounds from citrus against non-structural protein 3 protease of hepatitis C virus genotype 3a by fluorescence resonance energy transfer assay and mass spectrometry 被引量:1
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作者 Mahim Khan Waqar Rauf +2 位作者 Fazal-e-Habib Moazur Rahman Mazhar Iqbal 《World Journal of Hepatology》 2020年第11期976-992,共17页
BACKGROUND Hepatitis C virus genotype 3a(HCV G3a)is highly prevalent in Pakistan.Due to the elevated cost of available Food and Drug Administration-approved drugs against HCV,medicinal natural products of potent antiv... BACKGROUND Hepatitis C virus genotype 3a(HCV G3a)is highly prevalent in Pakistan.Due to the elevated cost of available Food and Drug Administration-approved drugs against HCV,medicinal natural products of potent antiviral activity should be screened for the cost-effective treatment of the disease.Furthermore,from natural products,active compounds against vital HCV proteins like non-structural protein 3(NS3)protease could be identified to prevent viral proliferation in the host.AIM To develop cost-effective HCV genotype 3a NS3 protease inhibitors from citrus fruit extracts.METHODS Full-length NS3 without co-factor non-structural protein 4A(NS4A)and codon optimized NS3 protease in fusion with NS4A were expressed in Escherichia coli.The expressed protein was purified by metal ion affinity chromatography and gel filtration.Citrus fruit extracts were screened using fluorescence resonance energy transfer(FRET)assay against the protease and polyphenols were identified as potential inhibitors using electrospray ionization-mass spectrometry(MS)/MS technique.Among different polyphenols,highly potent compounds were screened using molecular modeling approaches and consequently the most active compound was further evaluated against HCV NS4A-NS3 protease domain using FRET assay.RESULTS NS4A fused with NS3 protease domain gene was overexpressed and the purified protein yield was high in comparison to the lower yield of the full-length NS3 protein.Furthermore,in enzyme kinetic studies,NS4A fused with NS3 protease proved to be functionally active compared to full-length NS3.So it was concluded that co-factor NS4A fusion is essential for the purification of functionally active protease.FRET assay was developed and validated by the half maximal inhibitory concentration(IC50)values of commercially available inhibitors.Screening of citrus fruit extracts against the native purified fused NS4A-NS3 protease domain showed that the grapefruit mesocarp extract exhibits the highest percentage inhibition 91%of protease activity.Among the compounds identified by LCMS analysis,hesperidin showed strong binding affinity with the protease catalytic triad having S-score value of-10.98.CONCLUSION Fused NS4A-NS3 protease is functionally more active,which is effectively inhibited by hesperidin from the grapefruit mesocarp extract with an IC50 value of 23.32μmol/L. 展开更多
关键词 Hepatitis C virus genotype 3a non-structural protein 3 protease Fluorescence resonance energy transfer assay Citrus extract Mass spectrometry HESPERIDIN
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Retraction Note:Screening and identification of bioactive compounds from citrus against non-structural protein 3 protease of hepatitis C virus genotype 3a by fluorescence resonance energy transfer assay and mass spectrometry
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作者 Mahim Khan Waqar Rauf +2 位作者 Fazal-E-Habib Moazur Rahman Mazhar Iqbal 《World Journal of Hepatology》 2022年第7期1528-1529,共2页
Retraction note:Khan M,Rauf W,Habib F,Rahman M,Iqbal M.Screening and identification of bioactive compounds from citrus against non-structural protein 3 protease of hepatitis C virus genotype 3a by fluorescence resonan... Retraction note:Khan M,Rauf W,Habib F,Rahman M,Iqbal M.Screening and identification of bioactive compounds from citrus against non-structural protein 3 protease of hepatitis C virus genotype 3a by fluorescence resonance energy transfer assay and mass spectrometry.World J Hepatol 2020;12(11):976-992 PMID:33312423 DOI:10.4254/wjh.v12.i11.976.The online version of the original article can be found at https://www.wjgnet.com/1948-5182/full/v12/i11/976.htm. 展开更多
关键词 non-structural protein 3 Hepatitis C virus Genotype 3a Fluorescence resonance energy transfer
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Potential effect of hepatitis C Virus non-structural protein 4B on liver carcinogenesis
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作者 Xia Chen Changping Li Zhongqiong Wang Guanghong DU 《Journal of Nanjing Medical University》 2006年第6期387-391,共5页
Objective:To investigate the effect of hepatitis C virus non-structural protein 4B(HCV NS4B) on c-Myc, P53, ras gene expression" and apoptosis in hepatic cells and study the possible role that NS4B played in the c... Objective:To investigate the effect of hepatitis C virus non-structural protein 4B(HCV NS4B) on c-Myc, P53, ras gene expression" and apoptosis in hepatic cells and study the possible role that NS4B played in the carcinogenesis of heparoma. Methods: The recombinant plasmid(PCXN2-NS4B, PCXN2-P53) and the empty, vector were transfected or co-transfected into Chang liver cells with liposome. Screening was performed with G418. Plasmid mRNA was detected by RT-PCR. The pro rein expressions of c-Myc and ras genes were analyzed by immunocytochemistry. The expressions of wild-type P53 (wtp53) gene were detected by in situ hybridization. TUNEL(flow cytometry) was used for assessing the rate of apoptosis. Results:No expression of c-Myc gene was found in PCXN2 group. The expression of c-Myc gene in NS4B group was 21.3% + 1.2%. The ex pression of ras gene in PCXN2 group was lower than that in NS4B group. Compared with PCXN2 group, the expression of P53 mRNA was not promoted or inhibited in NS4B group. But the expression of P53 mRNA in NS4B-P53 group was lower than that in P53 group. In PCXN2, NS4B, P53 and NS4B-P53 group, the rates of apoptosis were 17.02% ± 1.24%, 11.94% ± 2.24%, 25.84% ± 3.49% and 18.34% ± 1.55% respectively. Conclusion :HCV NS4B induces the expression of c-Myc and ras gene. HCV NS4B may play a role in the inhibition of cell death through P53-dependent manner. Results from this study suggested that HCV NS4B might contribute to the viral carcinogenesis. 展开更多
关键词 non-structural protein 4B tumor suppressor gene ONCOGENE APOPTOSIS
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Expression of non-structural protein NS3 gene of Bombyx mori densovirus (China isolate) 被引量:7
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作者 Huijuan Yin Qin Yao Zhongjian Guo Fang Bao Wei Yu Jun Li Keping Chen 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2008年第4期239-244,共6页
The invertebrate parvovirus Bombyx mori Densonucleosis Virus type 3 (China isolate), named BmDNV-3, is a kind of bidensovirus. It is a new type of virus with unique replication mechanisms. To investigate the effects... The invertebrate parvovirus Bombyx mori Densonucleosis Virus type 3 (China isolate), named BmDNV-3, is a kind of bidensovirus. It is a new type of virus with unique replication mechanisms. To investigate the effects of the NS3 gene during viral DNA replication, a pair of primers was designed for amplifying NS3 gene of Bombyx mori densovirus (China isolate). Gene NS3 amplified was cloned into a prokaryotic expression vector pET-30a and the donor plasmid pFastBacHTe, respectively. The NS3 protein was expressed in Escherichia coli BL21. The pFastBacHTe-NS3 was transformed to E. coli DHIOBac. The recombinant bacmid baculoviruses (rBacmid-EGFP-NS3) isolated from the white colonies were transfected into BmN-4 cells using a transfection reagent. BraN-4 cells were infected with recombinant virus to express fusion proteins. The expression of fusion protein around 30 kDa in E. coli BL21 was identified by SDS-PAGE, Western blotting, and mass spectrometry. The expressed NS3 protein by B. mori nucleopolyhedrovirus bacmid system was confirmed by Western blotting using an anti-NS3 polyclonal antibody. And about 45 kDa protein was found. The expressed fusion protein was smaller than the expected size of EGFP-NS3, 55 kDa. Western blotting analysis indicated that EGFP-NS3 protein was expressed in infected larvae with smaller molecular size. 展开更多
关键词 BmDNV NS3 protein expression
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Prokaryotical expression of structural and non-structural proteins of hepatitis G virus 被引量:4
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作者 Ning-Shao Xia~1 Hai-Jie Yang~1 Jun Zhang~1 Chang-Qing Lin~1 Ying-Bin Wang~1 Juan Wang~1 Mei-Yun Zhan~2 MH Ng~3 1 Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering,Xiamen University,Xiamen 361005,Fujian Province,China2 Institute of Virology,Chinese Academy of Preventive Medicine Beijing 100052,China3 Department of Microbiology,Hoog Kong University,Hongkong,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第5期642-646,共5页
AIM To study the epitope distribution of hepatitis G virus (HGV) and to seek for the potential recombinant antigens for the development of HGV diagnositic reagents.METHODS Fourteen clones encompassing HGV gene fragmen... AIM To study the epitope distribution of hepatitis G virus (HGV) and to seek for the potential recombinant antigens for the development of HGV diagnositic reagents.METHODS Fourteen clones encompassing HGV gene fragments from core to NS3 and NS5 were constructed using prokaryotic expression vector pRSET and (or)pGEX. and expressed in E. coli. Western blotting and ELISA were used to detect the immunoreactivity of these recombinant proteins.``RESULTS One clone with HGV fragment from core to El(Gl). one from E2 (G31), three from NS3 (G6, G61, G7),one from NS5B (G821) and one chimeric fragment from NS3and NS5B (G61 821) could be expressed well and showed obvious immunoreactivity by Western blotting.One clone with I-KGV framment from NS5B (G82) was also well expressed, but could not show immunoreactivity by Western blotting. No obvious expression was found in the other six clones. All the expressed recombinant proteins were in inclusion body form, except the protein G61 which could be expressed in soluble form. Further purified recombinant proteins Gl, G,31, G61, G821 and G61 821were detected in indirected ELISA as coating antigen respectively. Only recombinant Gl could still show immunoreactivity, and the other four recombinant proteins failed to react to the HGV antibody positive sera.Western blotting results indicated that the immunoactivity of these four recombinant proteins were lost during purification.``CONCLUSION Core to El, E2. NS3 and NS5 fragment of HGV contain antigenic epitopes, which could be produced in prokaryotically expressed recombinant proteins. A high. yield recombinant protein (Gl) located in HGV core to E1 could remain its epitope after purification, which showed the potential that G1 could be used as a coating antigen to develop an ELISA kit for HGV specific antibody diagnosis. 展开更多
关键词 HEPATITIS agents GB/ GENETICS genes VIRAL VIRAL proteins/biosynthesis
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Expression and Activity Analysis of Non-Structural Protein 2 (NS2) of Bombyx mori Densovirus Zhenjiang Strain
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作者 ZHAO Pan TANG Shun-ming +3 位作者 LIU Tingx LIU Ting QIN Guang-xing GUO Xi-j ie 《Agricultural Sciences in China》 CSCD 2010年第12期1821-1828,共8页
The gene of the non-structure protein 2 (NS2) was cloned by PCR from the genome ofBombyx mori densovirus Zhenjiang strain (BmDNV-Z), inserted into prokaryotic expression vector pET28a to construct recombinant plas... The gene of the non-structure protein 2 (NS2) was cloned by PCR from the genome ofBombyx mori densovirus Zhenjiang strain (BmDNV-Z), inserted into prokaryotic expression vector pET28a to construct recombinant plasmid pET28a-NS2 and then expressed in bacteria Escherichia coli BL21 (DE3). The expressed recombinant protein was identified by SDS-PAGE and Western blot analysis. Then, the recombinant protein was purified by Ni-NTA column, renatured and tested for enzyme activities. The purified NS2 protein exhibited a helicase activity unwinding double-stranded DNA substrates into single-strand primers, and higher unwinding activity to polarity substrate. Similarly, the purified NS2 protein possessed an ATPase activity and its enzyme activity was 0.276 μmol gg^-1 h^-1 in this study. The results indicated that the non- structure protein which encoded by the gene of BmDNV-Z NS2 possesses the biological activities of helicase and ATPase, and the helicase prefers to polarity substrates. Based on these results, it is speculated that the gene of BmDNV-Z NS2 plays an important role in the viral DNA replication. 展开更多
关键词 Bombyx mori DENSOVIRUS non-structure protein EXPRESSION ACTIVITY
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Inhibition of Hepatitis C Virus Genotype 1a Non-Structural Proteins by Small Interference RNA in Human Hepatoma Cell Lines
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作者 Imran Shahid Waleed Hassan AlMalki +3 位作者 Shaia Saleh R. Almalki Ismail Muhammad AlTurkestany Hassan Ali AlGhamdi Saleh Ali AlMenshawi 《Pharmacology & Pharmacy》 2015年第11期502-517,共16页
Hepatitis C virus (HCV) infection and associated liver diseases are still challenging and represent a significant health care burden around the world. Although, the treatment strategies have been improved by the devel... Hepatitis C virus (HCV) infection and associated liver diseases are still challenging and represent a significant health care burden around the world. Although, the treatment strategies have been improved by the development of novel direct-acting antivirals, but such therapeutic options are still expensive and beyond the financial range of the most infected individuals in developing or even in resource replete countries. It demands an urgent need to search novel and improved alternate treatment strategies to treat the infection. The present study was aimed to develop an in vitro stable cell culture system, persistently expressing HCV genotype 1a non-structural genes and to characterize the inhibitory effects of synthetic siRNAs (short interference RNA) directed against the most conserved regions of nonstructural genes in an in vitro cell culture model. The continuous expression of nonstructural genes for more than 30 days post transfection was detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis in stable human hepatoma cell line (Huh-7). The gene expression studies revealed significantly reduced gene expression of HCV nonstructural genes (i.e., NS2, NS4A and NS5A) both at mRNA and protein levels when treated against genome specific synthetic siRNAs in stable cell lines (51%, 47% and 54% respectively, p < 0.05). Similarly, a vivid decrease in HCV viral titer was exhibited by synthetic siRNAs in an in vitro viral replicate cell culture model (58%, 48% and 50%, respectively, p < 0.05) determined by quantitative Real-Time PCR (qPCR). Our data indicate that siRNA mediated gene silencing may be considered a promising alternate treatment strategy against HCV in combination with other effective therapeutic regimens in future. 展开更多
关键词 HEPATITIS C VIRUS non-structural proteinS Stable Cell Line ANTI-HCV DRUGS Short Interference RNA
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Expression of Major B-cell Epitopes within the 2C Non-structural Protein of FMDV and Their Immunoreactivity
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作者 FU Yuan-fang LU Zeng-jun +3 位作者 TIAN Mei-na ZHANG Xiao-li LIU Zai-xin CAI Xue-peng 《畜牧兽医学报》 CAS CSCD 北大核心 2009年第S1期39-42,共4页
A pair of specific primers was designed from the 2C gene sequence of foot-and-mouth disease virus(FMDV)for amplification of a fragment including 174bp of the 5'-end and 279bp of the 3'-end of the2C gene,which ... A pair of specific primers was designed from the 2C gene sequence of foot-and-mouth disease virus(FMDV)for amplification of a fragment including 174bp of the 5'-end and 279bp of the 3'-end of the2C gene,which encoded an abundance of known B-cell epitopes of the protein.The amplified fragment was inserted into pET-30a plasmid(Novagen)via two unique endonuclease restriction sites,Nco I and Sal I.Sequencing confirmed that the open reading frame of interest was correctly inserted into the positive recombinant plasmid.The positive plasmid was transformed into the host bacteria BL21(DE3)pLys for protein expression.After induction by IPTG at 37℃for 5 hours,the expressed product was analyzed by SDSPAGE and Western blotting,confirming successful expression.The product is a 23kDa fusion protein and was shown to react with sera derived from FMDV-infected animals.This approach provides an useful antigen for establishing an enzyme-linked immunoelectro-transfer blot assay(EITB)diagnostic method,useful for differentiating FMDV-infected animals from those that been vaccinated. 展开更多
关键词 FMDV nonstructural protein 2C GENE EITB
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Expression and Application of the Recombinant Non-Structural Proteins of FMDV
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作者 孙涛 陆苹 方心葵 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第S1期61-64,85,共5页
FMDV non-structural protein gene(NSPs) 3ABC, 3AB, 2C and 3D were amplified and cloned into expression plasmid pET-32a(+). The recombinant NSPs were produced in E.coli and purified using Ni2+ affinity column. Weste... FMDV non-structural protein gene(NSPs) 3ABC, 3AB, 2C and 3D were amplified and cloned into expression plasmid pET-32a(+). The recombinant NSPs were produced in E.coli and purified using Ni2+ affinity column. Western-blotting indicated that the NSPs were expressed correctly. Using the recombinant NSPs, indirect ELISAs have been set up to distinguish FMDV-infected pigs from vaccinated ones. Experimental results indicate that the immunogenesity of recombinant 3AB protein is strong and can be the ideal antigen for detection; the immunogenecity of 2C is weak and sensitivity of the assay is low; 3D is not an ideal antigen ,for the specificity of assay based on 3D is low. 展开更多
关键词 FMDV non STRUCTURAL protein IMMUNOASSAY
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Cleft analysis of Zika virus non-structural protein 1
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作者 Somsri Wiwanitkit Viroj Wiwanitkit 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2017年第8期763-764,共2页
The non-strctural protein 1 is an important molecule of the viruses in flavivirus group including to Zika virus. Recently, the NS1 of Zika virus was discovered.There is still no complete information of the molecular i... The non-strctural protein 1 is an important molecule of the viruses in flavivirus group including to Zika virus. Recently, the NS1 of Zika virus was discovered.There is still no complete information of the molecular interaction of NS1 of Zika virus which can be the clue for explanation for its pathogenesis and further drug search. Here the authors report the cleft analysis of NS1 of Zika virus and the result can be useful for future development of good diagnostic tool and antiviral drug finding for management of Zika virus. 展开更多
关键词 Zika 病毒 非结构的蛋白质 1 劈开 FLAVIVIRUS
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Zika virus non-structural protein 4B interacts with DHCR7 to facilitate viral infection
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作者 Weijie Chen Yukun Li +8 位作者 Xiuling Yu Zhenwei Wang Wenbiao Wang Menglan Rao Yongkui Li Zhen Luo Qiwei Zhang Jinbiao Liu Jianguo Wu 《Virologica Sinica》 SCIE CAS CSCD 2023年第1期23-33,共11页
Zika virus(ZIKV)evolves non-structural proteins to evade immune response and ensure efficient replication in the host cells.Cholesterol metabolic enzyme 7-dehydrocholesterol reductase(DHCR7)was recently reported to im... Zika virus(ZIKV)evolves non-structural proteins to evade immune response and ensure efficient replication in the host cells.Cholesterol metabolic enzyme 7-dehydrocholesterol reductase(DHCR7)was recently reported to impact innate immune responses in ZIKV infection.However,the vital non-structural protein and mechanisms involved in DHCR7-mediated viral evasion are not well elucidated.In this study,we demonstrated that ZIKV infection facilitated DHCR7 expression.Notably,the upregulated DHCR7 in turn facilitated ZIKV infection and blocking DHCR7 suppressed ZIKV infection.Mechanically,ZIKV non-structural protein 4B(NS4B)interacted with DHCR7 to induce DHCR7 expression.Moreover,DHCR7 inhibited TANK-binding kinase 1(TBK1)and interferon regulatory factor 3(IRF3)phosphorylation,which resulted in the reduction of interferon-beta(IFN-β)and interferon-stimulated genes(ISGs)productions.Therefore,we propose that ZIKV NS4B binds to DHCR7 to repress TBK1 and IRF3 activation,which in turn inhibits IFN-βand ISGs,and thereby facilitating ZIKV evasion.This study broadens the insights on how viral non-structural proteins antagonize innate immunity to facilitate viral infection via cholesterol metabolic enzymes and intermediates. 展开更多
关键词 7-Dehydrocholesterol reductase(DHCR7) Interferon regulatory factor 3(IRF3) Interferon-beta(IFN-β) non-structural protein 4B(NS4B) TANK-Binding kinase 1(TBK1) Zika virus(ZIKV)
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Effects of drought on non-structural carbohydrates and C,N,and P stoichiometric characteristics of Pinus yunnanensis seedlings
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作者 Zhijuan Zhao Lina Wang +7 位作者 Yuanxi Liu Jianli Sun Jiandong Xiao Qiong Dong Lianfang Li Wanjie Zhang Chao Wang Junwen Wu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期90-102,共13页
To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,lig... To study non-structural carbohydrate character-istics and nutrient utilization strategies of Pinus yunnanen-sis under continuous drought conditions,2-year-old seed-lings were planted in pots with appropriate water,light and moderate and severe drought treatments[(80±5),(65±5),(50±5),and(35±5)%of field water-holding capacity].Non-structural carbohydrates,carbon(C),nitrogen(N),and phosphorus(P)concentrations were measured in each plant component.The results show that:(1)With increasing drought,non-structural carbohydrates gradually increased in leaves,stems,and coarse roots,while gradually decreased in fine roots;(2)C concentrations of all were relatively stable under different stress levels.Phosphorous utilization of each component increased under light and moderate drought conditions,while N and P utilization efficiency of each plant component decreased under severe drought.Growth was mainly restricted by N,first decreasing and then increasing with increased drought;(3)There was a correlation between the levels of non-structural carbohydrates and C,N,and P in each component.Changes in N concentration affected the interconversion between soluble sugar and starch,which play a regulatory role in the fluctuation of the concentration of non-structural carbohydrates;and,(4)Plasticity analysis showed that P.yunnanensis seedlings responded to drought mainly by altering starch concentration,the ratio of soluble sugar to starch in leaves and stems,and further by alter-ing N and P utilization efficiencies.Overall,these results suggest that the physiological activities of all organs of P.yunnanensis seedlings are restricted under drought and that trade-offs exist between different physiological indicators and organs.Our findings are helpful in understanding non-structural carbohydrate and nutrient adaptation mechanisms under drought in P.yunnanensis seedlings. 展开更多
关键词 Pinus yunnanensis seedlings DROUGHT non-structural carbohydrates C N P stoichiometric characteristics
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Irrigation regimes modulate non-structural carbohydrate remobilization and improve grain filling in rice(Oryza sativa L.)by regulating starch metabolism
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作者 Yuguang Zang Gaozhao Wu +10 位作者 Qiangqiang Li Yiwen Xu Mingming Xue Xingyu Chen Haiyan Wei Weiyang Zhang Hao Zhang Lijun Liu Zhiqin Wang Junfei Gu Jianchang Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1507-1522,共16页
Recently developed ‘super’ rice cultivars with greater yield potentials often suffer from the problem of poor grain filling, especially in inferior spikelets. Here, we studied the activities of enzymes related to st... Recently developed ‘super’ rice cultivars with greater yield potentials often suffer from the problem of poor grain filling, especially in inferior spikelets. Here, we studied the activities of enzymes related to starch metabolism in rice stems and grains, and the microstructures related to carbohydrate accumulation and transportation to investigate the effects of different water regimes on grain filling. Two ‘super’ rice cultivars were grown under two irrigation regimes of well-watered(WW) and alternate wetting and moderate soil drying(AWMD). Compared with the WW treatment,the activities of ADP glucose pyrophosphorylase(AGPase), starch synthase(StSase) and starch branching enzyme(SBE), and the accumulation of non-structural carbohydrates(NSCs) in the stems before heading were significantly improved, and more starch granules were stored in the stems in the AWMD treatment. After heading, the activities of α-amylase, β-amylase, sucrose phosphate synthase(SPS) and sucrose synthase in the synthetic direction(SSs)were increased in the stems to promote the remobilization of NSCs for grain filling under AWMD. During grain filling, the enzymatic activities of sucrose synthase in the cleavage direction(SSc), AGPase, StSase and SBE in the inferior spikelets were increased, which promoted grain filling, especially for the inferior spikelets under AWMD.However, there were no significant differences in vascular microstructures. The grain yield and grain weight could be improved by 13.1 and 7.5%, respectively, by optimizing of the irrigation regime. We concluded that the low activities of key enzymes in carbon metabolism is the key limitation for the poor grain filling, as opposed to the vascular microstructures, and AWMD can increase the amount of NSC accumulation in the stems before heading, improve the utilization rate of NSCs after heading, and increase the grain filling, especially in the inferior spikelets, by altering the activities of key enzymes in carbon metabolism. 展开更多
关键词 rice(Oryza sativa L.) non-structural carbohydrates(NsCs) enzymatic activity grain illing starch granules vascular bundle
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Variation analysis of the severe acute respiratory syndrome coronavirus putative non-structural protein 2 gene and construction of three-dimensional model
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作者 LUJia-hai ZHANGDing-mei +10 位作者 WANGGuo-ling GUOZhong-min ZHANGChuan-hai TANBing-yan OUYANGLi-ping LINLi LIUYi-min CHENWei-qing LINGWen-hua YUXin-bing ZHONGNan-shan 《Chinese Medical Journal》 SCIE CAS CSCD 2005年第9期707-713,共7页
Background The rapid transmission and high mortality rate made severe acute respiratory syndrome (SARS) a global threat for which no efficacious therapy is available now. Without sufficient knowledge about the SARS c... Background The rapid transmission and high mortality rate made severe acute respiratory syndrome (SARS) a global threat for which no efficacious therapy is available now. Without sufficient knowledge about the SARS coronavirus (SARS-CoV), it is impossible to define the candidate for the anti-SARS targets. The putative non-structural protein 2 (nsp2) (3CL pro , following the nomenclature by Gao et al, also known as nsp5 in Snidjer et al) of SARS-CoV plays an important role in viral transcription and replication, and is an attractive target for anti-SARS drug development, so we carried on this study to have an insight into putative polymerase nsp2 of SARS-CoV Guangdong (GD) strain. Methods The SARS-CoV strain was isolated from a SARS patient in Guangdong, China, and cultured in Vero E6 cells. The nsp2 gene was amplified by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into eukaryotic expression vector pCI-neo (pCI-neo/nsp2). Then the recombinant eukaryotic expression vector pCI-neo/nsp2 was transfected into COS-7 cells using lipofectin reagent to express the nsp2 protein. The expressive protein of SARS-CoV nsp2 was analyzed by 7% sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE). The nucleotide sequence and protein sequence of GD nsp2 were compared with that of other SARS-CoV strains by nucleotide-nucleotide basic local alignment search tool (BLASTN) and protein-protein basic local alignment search tool (BLASTP) to investigate its variance trend during the transmission. The secondary structure of GD strain and that of other strains were predicted by Garnier-Osguthorpe-Robson (GOR) Secondary Structure Prediction. Three-dimensional-PSSM Protein Fold Recognition (Threading) Server was employed to construct the three-dimensional model of the nsp2 protein.Results The putative polymerase nsp2 gene of GD strain was amplified by RT-PCR. The eukaryotic expression vector (pCI-neo/nsp2) was constructed and expressed the protein in COS-7 cells successfully. The result of sequencing and sequence comparison with other SARS-CoV strains showed that nsp2 gene was relatively conservative during the transmission and total five base sites mutated in about 100 strains investigated, three of which in the early and middle phases caused synonymous mutation, and another two base sites variation in the late phase resulted in the amino acid substitutions and secondary structure changes. The three-dimensional structure of the nsp2 protein was successfully constructed. Conclusions The results suggest that polymerase nsp2 is relatively stable during the phase of epidemic. The amino acid and secondary structure change may be important for viral infection. The fact that majority of single nucleotide variations (SNVs) are predicted to cause synonymous, as well as the result of low mutation rate of nsp2 gene in the epidemic variations, indicates that the nsp2 is conservative and could be a target for anti-SARS drugs. The three-dimensional structure result indicates that the nsp2 protein of GD strain is high homologous with 3CL pro of SARS-CoV urbani strain, 3CL pro of transmissible gastroenteritis virus and 3CL pro of human coronavirus 229E strain, which further suggests that nsp2 protein of GD strain possesses the activity of 3CL pro . 展开更多
关键词 severe acute respiratory syndrome CORONAVIRUS non-structural protein 2 gene three-dimensional structure
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Structural Basis for Complementary and Alternative Medicine:Phytochemical Interaction with Non-Structural Protein 2 Protease-A Reverse Engineering Strategy
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作者 G.Koushik Kumar G.Prasanna +1 位作者 T.Marimuthu N.T.Saraswathi 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2015年第6期445-452,共8页
Objective: To understand the druggability of the bioactive compounds from traditional herbal formulations "Nilavembu Kudineer" and "Swasthya Raksha Amruta Peya" to heal chikungunya virus (CHIKV) infection. Meth... Objective: To understand the druggability of the bioactive compounds from traditional herbal formulations "Nilavembu Kudineer" and "Swasthya Raksha Amruta Peya" to heal chikungunya virus (CHIKV) infection. Methods: The efficiency of twenty novel chemical entities from "Nilavembu Kudineer" and "Swasthya Raksha Amruta Peya" to inhibit CHIKV infection in silico were evaluated. Ligands were prepared using Ligprep module of Schr0dinger. Active site was identified using SiteMap program. Grid box was generated using receptor grid generation wizard. Molecular docking was carried out using Grid Based Ligand Docking with Energetics (GLIDE) program. Results: Molecular docking studies showed that among twenty compounds, andrographoside, deoxyandrographoside, neoandrographolide, 14-deoxy-11-oxoandrographolide, butoxone and oleanolic acid showed GLIDE extra precision (XP) score of-9.10,-8.72, -8.25,-7.38,-7.28 and -7.01, respectively which were greater than or comparable with chloroquine (reference compound) XP score (-7.08) and were found to interact with the key residues GLLI 1043, LYS 1045, GLY 1176, LEU 1203, HIS 1222 and LYS 1239 which were characteristic functional unit crucial for replication of CHIKV. Conclusion: The binding affinity and the binding mode of chemical entities taken from herbal formulations with non-structural protein 2 protease were understood and our study provided a novel strategy in the development and design of drugs for CHIKV infection. 展开更多
关键词 chikungunya virus non-structural protein 2 protease Grid Based Ligand Docking with Energetics score Nilavembu Kudineer Swasthya Raksha Amruta Peya
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Increasing grain weight and yield stability by increasing pre-heading non-structural carbohydrate reserves per spikelet in short-growth duration rice
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作者 Xing Li Ruichun Zhang +8 位作者 Ge Chen Jiaxin Xie Zhengwu Xiao Fangbo Cao Izhar Ali Anas Iqbal Abdul Wahab Min Huang Jiana Chen 《The Crop Journal》 SCIE CSCD 2023年第6期1912-1920,共9页
Rice yield stability is a breeding goal,particularly for short-growth duration rice,but its underlying mechanisms remain unclear.In an attempt to identify the relationship between yield stability and source–sink char... Rice yield stability is a breeding goal,particularly for short-growth duration rice,but its underlying mechanisms remain unclear.In an attempt to identify the relationship between yield stability and source–sink characteristics in short-growth duration rice,a field experiment was conducted at three sites(Yueyang,Liuyang,and Hengyang)in 2021 and 2022.This study compared yield,yield components,source–sink characteristics,and their stability between two stable-yielding short-growth duration rice cultivars,Zhongzao 39(Z-39)and Lingliangyou 268(L-268),and two unstable-yielding short-growth duration rice cultivars,Zhongjiazao 17(Z-17)and Zhuliangyou 819(Z-819).The stability of agronomic parameters was represented by the coefficient of variation(CV).The respective CVs of yield in Z-17,Z-819,Z-39,and L-268 were 10.2%,10.1%,4.5%,and 5.7%in 2021 and 19.7%,15.0%,5.4%,and 6.5%in 2022.The respective CVs of grain weight were 6.3%,5.7%,3.4%,and 4.5%in Z-17,Z-819,Z-39,and L-268 in 2021,and 8.1%,6.3%,1.5%,and 0.8%in 2022.The mean source capacity per spikelet and pre-heading non-structural carbohydrate reserves per spikelet(NSC_(pre))were 7%–43%and7%–72%lower in Z-819 and Z-17than in L-268 and Z-39 in 2021 and 2022.The mean quantum yield of photosystem II photochemistry of leaf,leaf area index,and specific leaf weight of L-268 and Z-39 were higher than those of Z-819 and Z-17 at the heading stage.This study suggests that high NSC_(pre),caused by great leaf traits before heading,increases source capacity per spikelet and its stability,thereby increasing the stability of grain weight and yield.Increasing NSC_(pre)is critical for achieving grain weight and yield stability in short-growth duration rice. 展开更多
关键词 non-structural carbohydrate Short-growth duration rice Source-sink characteristics Yield stability
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The contribution of steel wallposts to out-of-plane behavior of non-structural masonry walls
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作者 Fooad Karimi Ghaleh Jough 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第1期243-262,共20页
For years,non-structural masonry walls have received little attention by code developers and professional engineers.Recently,significant efforts have been made to shed more light on out-of-plane(OOP)behavior of non-st... For years,non-structural masonry walls have received little attention by code developers and professional engineers.Recently,significant efforts have been made to shed more light on out-of-plane(OOP)behavior of non-structural masonry walls.In updated provisions of the Iranian seismic code,bed joint reinforcements(BJRs)and steel wallposts have been suggested for use.BJRs are horizontal reinforcements;steel wallposts are vertical truss-like elements intended to provide additional OOP restraints for a wall.The contribution of BJRs has previously been investigated by the authors.This study is devoted to investigating the contribution of steel wallposts to the OOP behavior of non-structural masonry walls.Using pre-validated 3D finite element(FE)models,the OOP behavior of 180 non-structural masonry walls with varying configurations and details are investigated.The OOP pressure-displacement curve,ultimate strength,the response modification factor,and the cracking pattern are among the results presented in this study.It is found that steel wallposts,especially those with higher rigidity,can improve the OOP strength of the walls.The contribution of wallposts in the case of shorter length walls and walls with an opening are more pronounced.Results also indicate that masonry walls with wallpost generally have smaller modification factors compared to similar walls without wallpost. 展开更多
关键词 masonry wall wallpost wind post bed joint reinforcement non-structural masonry wall out-of-plane behavior
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Major royal-jelly proteins intake modulates immune functions and gut microbiota in mice 被引量:1
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作者 Hang Wu Shican Zhou +7 位作者 Wenjuan Ning Xiao Wu Xiaoxiao Xu Zejin Liu Wenhua Liu Kun Liu Lirong Shen Junpeng Wang 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期444-453,共10页
In this study,we investigated the effects of major royal jelly proteins(MRJPs)on the estrogen,gut microbiota,and immunological responses in mice.Mice given 250 or 500 mg/kg,not 125 mg/kg of MRJPs,enhanced the prolifer... In this study,we investigated the effects of major royal jelly proteins(MRJPs)on the estrogen,gut microbiota,and immunological responses in mice.Mice given 250 or 500 mg/kg,not 125 mg/kg of MRJPs,enhanced the proliferation of splenocytes in response to mitogens.The splenocytes and mesenteric lymphocytes activated by T-cell mitogens(Con A and anti-CD3/CD28 antibodies)released high levels of IL-2 but low levels of IFN-γand IL-17A.The release of IL-4 was unaffected by MRJPs.Additionally,splenocytes and mesenteric lymphocytes activated by LPS were prevented by MRJPs at the same dose as that required for producing IL-1βand IL-6,two pro-inflammatory cytokines.The production of IL-1β,IL-6,and IFN-γwas negatively associated with estrogen levels,which were higher in the MRJP-treated animals than in the control group.Analysis of the gut microbiota revealed that feeding mice 250 mg/kg of MRJPs maintained the stability of the natural intestinal microflora of mice.Additionally,the LEf Se analysis identified biomarkers in the MRJP-treated mice,including Prevotella,Bacillales,Enterobacteriales,Gammaproteobacteria,Candidatus_Arthromitus,and Shigella.Our results showed that MRJPs are important components of royal jelly that modulate host immunity and hormone levels and help maintain gut microbiota stability. 展开更多
关键词 Major royal-jelly proteins Immunity ESTROGEN Gut microbiota CYTOKINES
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The pathogenic mechanism of TAR DNA-binding protein 43(TDP-43)in amyotrophic lateral sclerosis 被引量:1
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作者 Xinxin Wang Yushu Hu Renshi Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期800-806,共7页
The onset of amyotrophic lateral sclerosis is usually characterized by focal death of both upper and/or lower motor neurons occurring in the motor cortex,basal ganglia,brainstem,and spinal cord,and commonly involves t... The onset of amyotrophic lateral sclerosis is usually characterized by focal death of both upper and/or lower motor neurons occurring in the motor cortex,basal ganglia,brainstem,and spinal cord,and commonly involves the muscles of the upper and/or lower extremities,and the muscles of the bulbar and/or respiratory regions.However,as the disease progresses,it affects the adjacent body regions,leading to generalized muscle weakness,occasionally along with memory,cognitive,behavioral,and language impairments;respiratory dysfunction occurs at the final stage of the disease.The disease has a complicated pathophysiology and currently,only riluzole,edaravone,and phenylbutyrate/taurursodiol are licensed to treat amyotrophic lateral sclerosis in many industrialized countries.The TAR DNA-binding protein 43 inclusions are observed in 97%of those diagnosed with amyotrophic lateral sclerosis.This review provides a preliminary overview of the potential effects of TAR DNAbinding protein 43 in the pathogenesis of amyotrophic lateral sclerosis,including the abnormalities in nucleoplasmic transport,RNA function,post-translational modification,liquid-liquid phase separation,stress granules,mitochondrial dysfunction,oxidative stress,axonal transport,protein quality control system,and non-cellular autonomous functions(e.g.,glial cell functions and prion-like propagation). 展开更多
关键词 amyotrophic lateral sclerosis axonal transport liquid-liquid phase separation noncellular autonomous functions oxidative stress PATHOGENESIS post-translational modification protein quality control system stress granules TAR DNA-binding protein 43(TDP-43)
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Dengue virus non-structural 1 protein interacts with heterogeneous nuclear ribonucleoprotein H in human monocytic cells
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作者 Drishya Diwaker Mishra K P +1 位作者 Ganju L Singh S B 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2016年第2期109-114,共6页
Objective: To study protein-protein interaction between heterogeneous nuclear ribonucleoprotein H(hn RNP H) and Dengue virus(DENV) proteins. Methods: DENV proteins were screened against the host hn RNP H protein, in o... Objective: To study protein-protein interaction between heterogeneous nuclear ribonucleoprotein H(hn RNP H) and Dengue virus(DENV) proteins. Methods: DENV proteins were screened against the host hn RNP H protein, in order to identify the host-viral protein-protein interactions in DENV infected THP-1 cells by co-immunoprecipitation. The co-localization of the interacting proteins was further confirmed by immunofluorescence microscopy. Results: The host protein hn RNP H was found to interact with DENV nonstructural 1 protein and help the virus to multiply in the cell. Conclusions: The non-structural 1 glycoprotein is a key modulator of host immune response and is also involved in viral replication. Therefore, disruption of this key interaction between hn RNP H and DENV nonstructural 1 could be an important therapeutic strategy for management of DENV infection. 展开更多
关键词 DENGUE virus non-structural 1 protein Heterogeneous nuclear RIBONUCLEOprotein H protein interactions
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