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Nilaparvata lugens and Sogatella furcifera are two primary planthoppers on rice throughout Asian countries and areas. Neonicotinoid insecticides, such as imidacloprid (IMI), have been extensively used to control rice planthoppers and IMI resistance consequently occurred with an important mechanism from the over‐expression of P450 genes. The induction of P450 genes by IMI may increase the ability to metabolize this insecticide in planthoppers and increase the resistance risk. In this study, the induction of P450 genes was compared in S. furcifera treated with IMI and nitromethyleneimidazole (NMI), in two planthopper species by IMI lethal dose that kills 85% of the population (LD85), and in N. lugens among three IMI doses (LD15, LD50 and LD85). When IMI and NMI at the LD85 dose were applied to S. furcifera, the expression changes in most P450 genes were similar, including the up‐regulation of nine genes and down‐regulation of three genes. In terms of the expression changes in 12 homologous P450 genes between N. lugens and S. furcifera treated with IMI at the LD85 dose, 10 genes had very similar patterns, such as up‐regulation in seven genes, down‐regulation in one gene and no significant changes in two genes. When three different IMI doses were applied to N. lugens, the changes in P450 gene expression were much different, such as up‐regulation in four genes at all doses and dose‐dependent regulation of the other nine genes. For example, CYP6AY1 could be induced by all IMI doses, while CYP6ER1 was only up‐regulated by the LD50 dose, although both genes were reported important in IMI resistance. In conclusion, P450 genes in two planthopper species showed similar regulation patterns in responding to IMI, and the two neonicotinoid insecticides had similar effects on P450 gene expression, although the regulation was often dose‐dependent. 相似文献
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Bing Li Hua Zhang Min Ni Bin-bin Wang Fan-chi Li Kai-zhun Xu Wei-de Shen Qing-you Xia Ping Zhao 《Molecular biology reports》2014,41(8):5135-5146
It was predicted that the genome of silkworm, Bombyx mori, has at least 79 P450 genes; however, P450 genes that are related to the catabolism of exogenous compounds were not reported. In this study we cloned two CYP4 (named CPY4M5 and CYP4M9) and four CYP6 (named CYP6AB5, CYP6AE9, CYP6AE22 and CYP6AU1) genes by using both bioinformatics and RT-PCR approaches. Sequence analysis showed that these genes contained conserved P450 gene sequence regions and one conserved intron. CYP4M5 and CYP4M9 genes were clustered together in a mode of “head-to-tail” possibly due to gene duplication. Blast analysis showed that these P450 genes shared significant similarity with CYP4 and CYP6 genes that are involved in the catabolism and detoxification of exogenous compounds in other insect species. RT-PCR results showed that these P450 genes were highly expressed in the midgut and fat body of B. mori. As the instar age increased, these P450 genes exhibit different expression patterns. When B. mori was exposed to 1.75 × 10?5 % of cypermethrin, 3.5 × 10?6 % of cypermethrin and 0.1 % of rutin, expression of CYP6AB5 was increased by 2.3-fold, 2.2-fold and 1.9-fold, respectively. Exposure of B. mori to 0.1 % quercetin does not change the expression of CYP6AB5. In contrast, expression of the other five P450 genes was inhibited after exposed to these compounds. 相似文献
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Elizeu S. Farias Tamíris A. Araújo Gabriela C. Resende Júlia N. D. Campos Mirian F. Pimentel Elson S. Alvarenga Marcelo C. Picano 《化学与生物多样性》2019,16(3)
Phthalides and their precursors have demonstrated a large variety of biological activities. Eighteen phthalides were synthesized and tested on the stored grain pest Rhyzopertha dominica. In the screening bioassay, compounds rac‐(2R,2aS,4R,4aS,6aR,6bS,7R)‐7‐bromohexahydro‐2,4‐methano‐1,6‐dioxacyclopenta[cd]pentalen‐5(2H)‐one ( 15 ) and rac‐(3R,3aR,4R,7S,7aS)‐3‐(propan‐2‐yloxy)hexahydro‐4,7‐methano‐2‐benzofuran‐1(3H)‐one ( 17 ) showed mortality similar to the commercial insecticide, Bifenthrin® (≥90 %). The time (LT50) and dose (LD50) necessary to kill 50 % of the R. dominica population were determined for the most efficacious phthalides 15 and 17 . Compound 15 presented the lowest LD50 (1.97 μg g?1), being four times more toxic than Bifenthrin® (LD50=9.11 μg g?1). Both compounds presented an LT50 value equal to 24 h. When applied at a sublethal dose, both phthalides (especially compound 15 ), reduced the emergence of the first progeny of R. dominica. These findings highlight the potential of phthalides 15 and 17 as precursors for the development of insecticides for R. dominica control. 相似文献
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In this study we investigated genetic polymorphisms of five metabolizing genes and their association with occupational chronic manganism. We recruited 49 patients with chronic manganism and 50 unrelated healthy control subjects who were welders and ferromanganese smelters and occupationally exposed to manganese dust and fume in the same workshops from three metallurgical industries. The controls were matched to the cases by sex, age, cigarette and alcohol intake, as well as the manganese exposure duration. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to genotype the cytochrome P450 2D6L gene (CYP2D6L) and the NAD(P)H:quinone oxidoreductase gene (NQO1). Allele-specific PCR was used to detect the cytochrome P450 1A1 gene (CYP1A1), and the glutathione-S-transferase mu and theta genes (GSTM and GSTT). The frequency of polymorphic alleles, a mutation of CYP2D6L, was significantly lower in patients with chronic manganism (16.3%) than in controls (29.0%). Individuals with the homozygote polymorphism (L/L) of CYP2D6 had a 90% decreased risk of chronic manganism compared with the wild-type (Wt/Wt) (odds ratio =0.10, 95% confidence interval = 0.01-0.82). A significant association between the CYP2D6 genotype subgroup and the latency of chronic manganese poisoning was also found. Patients who had homozygous (L/L) or heterozygous (Wt/L) mutant alleles developed manganism an average of 10 years later than those who were homozygous wildtype (Wt/Wt). However, the allele and genotype frequencies of CYP1A1 and NQO1 genes were distributed similarly in cases and controls. In addition, no difference in the frequencies of GSTM1 and GSTT1 null genotypes were observed between cases and controls. The results suggest that CYP2D6L gene polymorphism might influence susceptibility to manganese-induced neurotoxicity. However, because of limited sample size, our results should be validated in large-scale studies. 相似文献
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Takeaki Nishibori Karven Cooray Huabao Xiong Ikuo Kawamura Masashi Fujita Masao Mitsuyama 《Microbiology and immunology》1995,39(5):343-349
Five chromosomal genes, prfA, plcA, hlyA, mpl and plcB, are implicated in the virulence of Listeria monocytogenes and some of these genes have been used for the identification of bacteria by polymerase chain reaction (PCR). Using 6 strains of L. monocytogenes and 3 L. innocua strains, the relationship was examined between the presence of five virulence-associated genes and actual virulence to mice in terms of 50% lethal dose (LD50), bacterial viability in the organ of infected mice and the intracellular growth in cultured macrophages. None of the five genes could be amplified by PCR in all the L. innocua strains and they were actually avirulent to mice. All L. monocytogenes strains were shown to be virulent and to have intact virulence-associated genes except for the strain ATCC15313. This particular strain was revealed to be avirulent and defective in hlyA and plcA in PCR amplification. It was suggested that PCR detection of genes prfA, mpl, or plcB may not be sufficient to detect virulent strains of L. monocytogenes. It appeared that the ability to produce listeriolysin O (LLO), which is encoded by hlyA, was critical for the expression of virulence regardless of the amount of LLO produced. 相似文献
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This study examines the genetic variations and mechanisms involved in the development of permethrin resistance in individual mosquitoes from a field population of Culex quinquefasciatus, HAmCqG0, and characterizes susceptible reference lines of mosquitoes with a similar genetic background to the field HAmCqG0 strain. Six upregulated cytochrome P450 genes, CYP9M10, CYP9J34, CYP6P14, CYP9J40, CYP6AA7, and CYP4C52v1, previously identified as being upregulated in the larvae of resistant HAmCqG8 mosquitoes were examined in the larvae of 3 strains (susceptible S‐Lab, parental HAmCqG0 and permethrin‐selected highly resistant HAmCqG8) and 8 HAmCqG0 single‐egg raft colonies, covering a range of levels of susceptibility/resistance to permethrin and exhibiting different variations in the expression of A and/or T alleles at the L‐to‐F kdr locus of the sodium channel. The 2 lines with the lowest tolerance to permethrin and bearing solely the susceptible A allele at the L‐to‐F kdr locus of the sodium channels, from colonies Cx_SERC5 and Cx_SERC8, showed lower or similar levels of all 6 of the P450 genes tested compared with the S‐Lab strain, suggesting that these 2 lines could be used as the reference mosquitoes in future studies characterizing insecticide resistance in HAmCq mosquitoes. This study also provides a detailed investigation of the mechanisms involved in insecticide resistance in individuals within a population: individuals with elevated levels of resistance to permethrin all displayed one or more potential resistance mechanisms–either elevated levels of P450 gene expression, or L‐to‐F mutations in the sodium channel, or both. 相似文献
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R. A. Tschirret-Guth L. S. Koo P.R. Ortiz de Montellano 《Journal of biological inorganic chemistry》2000,5(2):204-212
CYP119, the first thermophilic P450 enzyme, reacts much more slowly than CYP101 (P450cam) with aryldiazenes to give σ-bonded aryl-iron complexes. The CYP119 complexes are stable anaerobically at 80 °C but are readily oxidized by O2 to give the N-arylprotoporphyrin IX regioisomers. The aryl shift can also be initiated in the absence of O2 by K3Fe(CN)6. In contrast, the corresponding CYP101 complexes are insensitive to O2 but decompose at temperatures above 50 °C owing to denaturation of the protein. The rate of the CYP119 aryl shift is decreased
by electron-withdrawing substituents, with ρ=−1.50 for both the O2- and K3Fe(CN)6-dependent reactions. A similar dependence (ρ=−0.90) is observed for the K3Fe(CN)6-dependent CYP101 shift. The enthalpies and entropies of activation suggest that the CYP119 and CYP101 K3Fe(CN)6-mediated reactions are similar, but the CYP119 O2-dependent reaction proceeds via a different transition state. In all cases, the rate-determining step is oxidation of the
aryl-iron complex. The temperature dependence of the O2- and K3Fe(CN)6-dependent CYP119 shifts provides evidence for temperature-dependent equilibration of two active site conformations. The oxygen
sensitivity of the CYP119 aryl-iron complexes, and the temperature dependence of their rearragement, reflect the unique active
site properties of this thermophilic P450 enzyme.
Received: 12 August 1999 / Accepted: 8 December 1999 相似文献
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Gaspar PA Hutz MH Salzano FM Hill K Hurtado AM Petzl-Erler ML Tsuneto LT Weimer TA 《American journal of physical anthropology》2002,119(3):249-256
Polymorphisms at the TP53, cytochrome P‐450 (CYP), and glutathione S‐transferase (GST) genes are related to cancer susceptibility and present high diversity in allele frequencies among ethnic groups. This study concerns the CYP2E1, GSTM1, and GSTT1 polymorphisms in seven Amerindian populations (Xavante, Guarani, Aché, Wai Wai, Zoró, Surui, and Gavião). Polymorphic sites at CYP1A1 and TP53 were also studied in the Aché and Guarani tribes and compared with previous results about these systems already obtained in the other populations. The CYP2E1*5B haplotype showed, respectively, the highest and the lowest frequencies already observed in human groups. High frequencies of CYP1A1*2A and CYP1A1*2C alleles and mostly low values of GSTM1*0/*0 and GSTT1*0/*0 genotypes were observed. These data may be interpreted as being due to genetic drift or selection for these high‐frequency CYP1A1 alleles and against GST null genotypes during America's colonization. Intrapopulation diversity varied from 0.19 (Guarani) to 0.38 (Surui), and 90% of the total diversity was due to the variability within populations. The relationships between these Amerindians and with other ethnic groups were evaluated based on DA distances and the neighbor‐joining method. Low correlation was observed between genetic relationships and geographic distances or linguistic groups. In the TP53 comparison with other ethnic groups, Amerindians clustered together and then joined Chinese populations. The cluster analysis seems to indicate that the Aché tribe might descend from a Gê group that could have first colonized that Paraguayan region, but had also assimilated some amount of the Guarani gene pool, maybe through intertribal admixture. Am J Phys Anthropol 119:249–256, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
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Investigation of expression and activity levels of primary rat hepatocyte detoxication genes under various flow rates and cell densities in microfluidic biochips
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Régis Baudoin Giulia Alberto Audrey Legendre Patrick Paullier Marie Naudot Marie‐José Fleury Sébastien Jacques Laurent Griscom Eric Leclerc 《Biotechnology progress》2014,30(2):401-410
We investigated the behavior of primary rat hepatocytes in biochips using a microfluidic platform (the integrated dynamic cell culture microchip). We studied the effects of cell inoculation densities (0.2–0.5 × 106 cells/biochip) and perfusion flow rates (10, 25, and 40 µL/min) during 72 h of perfusion. No effects were observed on hepatocyte morphology, but the levels of mRNA and CYP1A2 activity were found to be dependent on the initial cell densities and flow rates. The dataset made it possible to extract a best estimated range of parameters in which the rat hepatocytes appeared the most functional in the biochips. Namely, at 0.25 × 106 inoculated cells cultivated at 25 µL/min for 72 h, we demonstrated better induction of the expression of all the genes analyzed in comparison with other cell densities and flow rates. More precisely, when primary rat hepatocytes were cultivated at these conditions, the time‐lapse analysis demonstrated an over expression of CYP3A1, CYP2B1, ABCC1b and ABCC2 in the biochips when compared to the postextraction levels. Furthermore, the AHR, CYP1A2, GSTA2, SULT1A1, and UGT1A6 levels remained higher than 50% of the postextraction values whereas values of HNF4α, CEBP, and PXR remained higher than 20% during the duration of the culture process. Nevertheless, an important reduction in mRNA levels was found for the xenosensors CAR and FXR, and the related CYP (CYP2E1, CYP7A1, CYP3A2, and CYP2D2). CYP1A2 functionality was illustrated by 700 ± 100 pmol/h/106 cells resorufin production. This study highlighted the functionality in optimized conditions of primary rat hepatocytes in parallelized microfluidic cultures and their potential for drug screening applications. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 30:401–410, 2014 相似文献
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Two full‐length P450 cDNAs, CYP6AX1 and CYP6AY1, were cloned from the brown planthopper Nilaparvata lugens Stål (Homoptera: Delphacidae). Both CYP6AX1 and CYP6AY1 are typical microsomal P450s and their deduced amino acid sequences share common characteristics with other members of the insect P450 CYP6 family. CYP6AX1 and CYP6AY1 show the highest percent identity (36%) of amino acid to each other; both of them have 31–33% amino acid identity with CYP6B1 from Papilio polyxenes (Lepidoptera: Papilionidae), CYP6B4 from Papilio glaucus (Lepidoptera: Papilionidae), and CYP6B8 from Helicoverpa zea (Lepidoptera: Noctuidae). Phylogenetic analysis showed the clustering of CYP6AX1 and CYP6AY1 was in the clade including CYP6AE1 from Depressaria pastinacella (Lepidoptera: Oecophoridae) and the CYP6B family members from Helicoverpa and Papilio species. Northern blot analysis revealed that both of the P450s were induced by the resistant rice variety B5 (Oryza sativa L), and CYP6AY1 was expressed at a higher level than CYP6AX1. The results suggest that more than one P450s are likely involved in metabolism of rice allelochemicals and that they are possibly important components in adaptation of Nilaparvata lugens to host rice. Arch. Insect Biochem. Physiol. 64:88–99, 2007. © 2007 Wiley‐Liss, Inc. 相似文献
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【目的】为明确杀虫剂亚致死剂量对草地贪夜蛾Spodoptera frugiperda细胞色素P450基因表达的影响。【方法】本研究采用叶片浸渍法测定了3种杀虫剂[氯虫苯甲酰胺、甲氨基阿维菌素苯甲酸盐和苏云金杆菌Bacillus thuringiensis(Bt)]对草地贪夜蛾2龄幼虫的毒力,以及通过实时荧光定量PCR(real-time quantitative PCR, RT-qPCR)技术测定了这3种杀虫剂亚致死剂量(LC10)处理后48 h时草地贪夜蛾2龄幼虫16个P450基因的表达量。【结果】氯虫苯甲酰胺、甲氨基阿维菌素苯甲酸盐和Bt对草地贪夜蛾2龄幼虫的LC10值分别为0.931, 0.283和1 089.688 mg/L。2龄幼虫受LC10氯虫苯甲酰胺胁迫后,13个P450基因(CYP4G75,CYP6AB12,CYP6B50,CYP321A7,CY321A8,CYP321A9,CYP321A10,CYP321B1,CYP337B5,CYP9A59,CYP9A58,CYP6AE44及CYP6AE43)表达上调... 相似文献
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R.S. Oliveira S.E. Ferreira L.C.M. Ribeiro J. Tannús-Neto 《Biocontrol Science and Technology》2013,23(1):79-91
While the aphid Lipaphis pseudobrassicae (Davis) (Hemip.: Aphididae: Macrosiphini) is considered one of the preferred hosts of Diaeretiella rapae (McIntosh) (Hym.: Braconidae: Aphidiinae) in several parts of the world, field surveys in Uberlandia (Brazil) found parasitism of this aphid to not exceed 10%. This study sought to determine the cause of this low parasitism, as well as the effects of parasitism on the intrinsic growth rate of the aphid population. We evaluated parasitism, percentage emergence, developmental time, longevity, number of attacks and number of parasitoid larvae in L. pseudobrassicae and compared these to the same characteristics in Brevicoryne brassicae (L.) and Myzus persicae (Sulzer). The lowest percentage of parasitism was found in L. pseudobrassicae, followed by M. persicae and B. brassicae. The ratio between the number of parasitoid larvae and the number of ovipositions in L. pseudobrassicae ranged from 0.02 to 0.03, while, in B. brassicae, it was between 0.41 and 0.44 and, in M. persicae, between 0.62 and 0.80, indicating high mortality rates of early stages of D. rapae in L. pseudobrassicae. Parasitism by D. rapae reduced the rm of L. pseudobrassicae. The rm for parasitised aphids was only 63% of that for unparasitised aphids. However, no hosts died before reaching adulthood, and 83% of parasitised aphids were still able to reproduce. As a result, the rm of the aphid was positive, resulting in population growth of L. pseudobrassicae, even among individuals parasitised during the second instar. Our results indicate the existence of L. pseudobrassicae genotypes that are completely resistant to D. rapae. 相似文献
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【背景】猪链球菌4型(Streptococcus suis serotype 4,SS4)分离率日益升高,对养殖业和公共卫生安全造成严重危害,目前尚无有效的SS4疫苗。【目的】筛选致病力强、抗原性好、遗传性状稳定的SS4疫苗菌种。【方法】以7株SS4分离株(代号为A1—A7)为受试菌株,通过累积法测定菌株半数致死量(LD50),ELISA测定免疫小鼠血清中IgG效价,攻毒保护试验测定免疫保护率,并采集小鼠脏器观察病理组织学变化。再连续传代培养受试菌株,分别对第10、20、30代菌株进行致病性和抗原性试验。【结果】A1—A7菌株对小鼠的LD50分别为2.19×108、1.76×108、1.83×108、1.01×108、4.05×108、1.19×108和9.03×107 CFU。二免7 d后,A1、A2、A3、A4、A6、A7免疫组IgG效价分别为1:1 600、1:1 600、1:3 200、1:6 400、1:3 200和1:6 400,免疫保护率分别为30%、30%、50%、70%、60%和80%,而且A4、A7免疫组小鼠组织病变较其余4组轻微。体外传至30代后,A4菌株的LD50上升至3.81×108 CFU,IgG效价下降至1:1 600,免疫保护率下降至40%,而A7菌株的LD50上升至2.49×108 CFU,IgG效价和免疫保护率稳定保持为1:6 400和80%,而且A7免疫组小鼠的组织病变较A4免疫组轻微。【结论】A7菌株(原始编号为HBgu18-4)具有强致病力和良好的抗原性,而且遗传性状均一、稳定,可作为SS4制苗候选菌株。 相似文献
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In this study, the expression patterns of four ferritin genes (PpFer1, PpFer2, PpFer3, and PpFer4) in pear were investigated using quantitative real-time PCR. Analysis of tissue-specific expression revealed higher expression
level of these genes in leaves than in other tested tissues. These ferritin genes were differentially expressed in response
to various abiotic stresses and hormones treatments. The expression of ferritin wasn’t affected by Fe(III)-citrate treatment.
Abscisic acid significantly enhanced the expression of all four ferritin genes, especially PpFer2, followed by N-benzylyminopurine, gibberellic acid, and indole-3-acetic acid. The expression peaks of PpFer1 and PpFer3 in leaves appeared at 6, 6, and 12 h, respectively, after pear plant was exposed to oxidative stress (5 mM H2O2), salt stress (200 mM NaCl), and heat stress (40°C). A significant increase in PpFer4 expression was detected at 6 h after salt stress or heat stress. The expression of ferritin genes was not altered by cold
stress. These results suggested that ferritin genes might be functionally important in acclimation of pear to salt and oxidative
stresses. Hormone treatments had no significant effect on expression of ferritin genes compared to abiotic stresses. This
showed accumulation of ferritin genes could be operated by different transduction pathways under abiotic stresses and hormones
treatments. 相似文献
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To enhance our understanding of brassinosteroid (BR) biosynthesis in rice, we attempted to identify putative rice homologs
of Arabidopsis CYP90A1/ CPD and related mutants. Two candidate genes, designated CYP90A3/OsCPD1 and CYP90A4/OsCPD2, are located on chromosomes 11 (2.0 cM) and 12 (1.9 cM), respectively. Based on sequence similarity with the Arabidopsis CYP90A1/CPD gene, we predict that the CYP90A3/OsCPD1 and CYP90A4/OsCPD2 gene products function as C-23α hydroxylases in the BR biosynthesis pathway. Both are broadly expressed in wild-type rice,
and their expression is regulated by a feedback mechanism. A retrotransposon insertion mutant of CYP90A3/OsCPD1, oscpd1-1, did not produce any BR-deficient phenotype or feedback upregulation of genes for BR biosynthesis enzymes. These results
indicate that if, as predicted, the CYP90A3/OsCPD1 and CYP90A4/OsCPD2 genes do function in the BR biosynthesis pathway, they may each have enough capacity to catalyze BR biosynthesis on their
own. As a consequence, the oscpd1-1 mutant may not be deficient in endogenous BRs. Interestingly, BR biosynthesis enzymes except C-6 oxidase are encoded by plural
genes in rice but by single genes in Arabidopsis (again, except C-6 oxidase). On the basis of these findings, we discuss the differences in BR biosynthesis between rice and
Arabidopsis. 相似文献
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M. I. Khan Musa Kaleem Baloch Muhammad Ashfaq 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):343-350
Six novel triorganotin(IV) 2-maleimidopropanoato complexes: R3SnOCOCH3(CH)(COCH)2, (R: Me(1), Et(2), n-Pr(3), n-Bu(4), Ph(5), Bz(6) have been synthesized. Their solid-state configuration has been determined by FT IR and 119mSn Mössbauer spectroscopy. The tin(IV) atom is five-coordinated in all the complexes with 2-maleimidopropanoic acid behaving as a monoanionic bidentate ligand coordinating the tin(IV) atom through a chelating or bridging carboxylate group. The solution-state configuration has been elucidated by means of 1H-, 13C- and 119Sn-NMR spectroscopy which assigned a tetrahedron. Elemental analysis and FAB MS data also supported a 1:1 metal to ligand stoichiometry. The title complexes have been screened in vitro for anti-tumour, anti-fungal, anti-leishmanial and urease inhibition activities and displayed promising results. 相似文献