This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase （BmCarE） in the midguts, the differential expression of BmCarE gene （bmcare） in the midguts, and the abil...This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase （BmCarE） in the midguts, the differential expression of BmCarE gene （bmcare） in the midguts, and the ability of Bombyx mori resistant to densonucleosis virus （BmDNV）, and to elucidate the molecular mechanism of resistance to BmDNV-Z. With two silkworm strains, HUABA, which is susceptible to BmDNV-Z, and BC8 （a near isogenic line of HUABA）, which is completely resistant to the same virus, as materials, the activity of BmCarE in the midgut was determined by Bio-Tek Synergy, and the differential expression of bmcare between the two strains was investigated by real-time fluorescence quantitative PCR, both at 12, 36, and 72 h post oral inoculation of the two strains with virus （hereafter referred as inoculation）. While the activity of BmCarE in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculated group, and the HUABA control group by 3.28, 2.26, and 3.02 times, respectively, with the difference being highly significant （P 〈 0.01）, there was no statistical difference among the other groups. The relative expression level of bmcare in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculation group, and the HUABA control group by 17.714, 21.76, and 15.09 times, respectively, with the difference being highly significant （P 〈 0.01）, and there was no statistical difference among other groups. The elevation of BmCarE activity and expression level of bmcare in the resistant strain at 12 h post inoculation may relate to the resistant gene （nsd/nsd） and the stimulation of BmDNV-Z. The molecular basis for the elevation of BmCarE activity in the resistant strain BC8 may be the change in the expression level of bmcare.展开更多
BACKGROUND： Pesticides are used to control various pests of agricultural crops worldwide. Despite their agricultural benefits, pesticides are often considered a serious threat to the environment because of their pers...BACKGROUND： Pesticides are used to control various pests of agricultural crops worldwide. Despite their agricultural benefits, pesticides are often considered a serious threat to the environment because of their persistence. Pyrethroids are synthetic derivates of pyrethrins, which are natural organic insecticides procured from the flowers of Chrysanthemum cinerariaefolium and C. coccineum. Pyrethroids are classified into two groups class Ⅰ and class Ⅱ-based on their toxicity and physical properties. These pyrethroids are now used in many synthetic insecticides and are highly specific against insects; they are generally used against mosquitoes. The prominent site of insecticidal action ofpyrethroids is the voltage-sensitive sodium channels. METHODS and RESULTS： Pyrethroids are found to be stable, and they persist in the environment for a long period. This article provides an overview of the different classes, structure, and insecticidal properties of pyrethroid. Furthermore, the toxicity of pyrethroids is also discussed with emphasis on bioremediation to alleviate pollution. CONCLUSIONS： The article focuses on various microorganisms used in the degradation ofpyrethroids, the molecular basis of degradation, and the role of carboxylesterase enzymes and genes in the detoxification of pyrethroid.展开更多
基金This work was supported by High Technology Research and Development Program of China （2005CB121000） Natural Science Foundation of Jiangsu Province, China （BK2006074）.
文摘This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase （BmCarE） in the midguts, the differential expression of BmCarE gene （bmcare） in the midguts, and the ability of Bombyx mori resistant to densonucleosis virus （BmDNV）, and to elucidate the molecular mechanism of resistance to BmDNV-Z. With two silkworm strains, HUABA, which is susceptible to BmDNV-Z, and BC8 （a near isogenic line of HUABA）, which is completely resistant to the same virus, as materials, the activity of BmCarE in the midgut was determined by Bio-Tek Synergy, and the differential expression of bmcare between the two strains was investigated by real-time fluorescence quantitative PCR, both at 12, 36, and 72 h post oral inoculation of the two strains with virus （hereafter referred as inoculation）. While the activity of BmCarE in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculated group, and the HUABA control group by 3.28, 2.26, and 3.02 times, respectively, with the difference being highly significant （P 〈 0.01）, there was no statistical difference among the other groups. The relative expression level of bmcare in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculation group, and the HUABA control group by 17.714, 21.76, and 15.09 times, respectively, with the difference being highly significant （P 〈 0.01）, and there was no statistical difference among other groups. The elevation of BmCarE activity and expression level of bmcare in the resistant strain at 12 h post inoculation may relate to the resistant gene （nsd/nsd） and the stimulation of BmDNV-Z. The molecular basis for the elevation of BmCarE activity in the resistant strain BC8 may be the change in the expression level of bmcare.
文摘BACKGROUND： Pesticides are used to control various pests of agricultural crops worldwide. Despite their agricultural benefits, pesticides are often considered a serious threat to the environment because of their persistence. Pyrethroids are synthetic derivates of pyrethrins, which are natural organic insecticides procured from the flowers of Chrysanthemum cinerariaefolium and C. coccineum. Pyrethroids are classified into two groups class Ⅰ and class Ⅱ-based on their toxicity and physical properties. These pyrethroids are now used in many synthetic insecticides and are highly specific against insects; they are generally used against mosquitoes. The prominent site of insecticidal action ofpyrethroids is the voltage-sensitive sodium channels. METHODS and RESULTS： Pyrethroids are found to be stable, and they persist in the environment for a long period. This article provides an overview of the different classes, structure, and insecticidal properties of pyrethroid. Furthermore, the toxicity of pyrethroids is also discussed with emphasis on bioremediation to alleviate pollution. CONCLUSIONS： The article focuses on various microorganisms used in the degradation ofpyrethroids, the molecular basis of degradation, and the role of carboxylesterase enzymes and genes in the detoxification of pyrethroid.
