Vibrio harveyi, known as a pathogenic bacterium caused severe secondary bacterial infections of the large yellow croaker Larimichthys crocea, was identified as an endosymbiont in the marine parasitic ciliate protozoan...Vibrio harveyi, known as a pathogenic bacterium caused severe secondary bacterial infections of the large yellow croaker Larimichthys crocea, was identified as an endosymbiont in the marine parasitic ciliate protozoan Cryptocaryon irritans. Meta 16 S sequencing method was used to identify the bacterial flora in C. irritans, and V.harveyi was isolated via culture-dependent method. Vibrio harveyi was observed in cytoplasm of C. irritans at the stage of tomont both by transmission electron microscopy and by Fluorescence in situ hybridization; no signal,however, was detected in nucleus area. The relationship between V. harveyi and C. irritans and the role of endosymbiotic V. harveyi in C. irritans merit further investigation.展开更多
Several studies have required Haematobia irritans (L.) raising in laboratory. The present study assessed two methods of inoculating immature forms of H. irritans to obtain adults. In 2007, 15 Nellore steers (Bos indic...Several studies have required Haematobia irritans (L.) raising in laboratory. The present study assessed two methods of inoculating immature forms of H. irritans to obtain adults. In 2007, 15 Nellore steers (Bos indicus) (L.) were used for the collection of feces free of anthelmintic treatment and flies to produce for eggs and larva. For method I, 30 eggs were incubated in square filter paper (5 × 5 cm) and deposited on bovine feces (500 g) where they were kept until hatching and spontaneous penetration of larvae (L1) into the fecal mass. After 24 h, eggs were analyzed under a stereoscope microscope (40×) for the number of larvae that instinctively penetrated the feces. In method II, larvae were obtained only by natural egg hatching. At birth, 30 larvae were collected and individually inoculated, directly onto the fecal plate by employing a moistened brush. The tests were carried out at controlled temperature (28°C ± 2°C) and saturated humidity (80%) until the emergence of flies with both methods. The number of emerged flies was considered in the result. Using method I, 276 (76.7%) flies emerged from 360 inoculated eggs, while using method II, 283 (78.6%) flies emerged from 360 inoculated larvae. There was no significant difference (P = 0.7821) between methods for the number of flies;however, the proportion between males and females by means of larva inoculation was different from 1:1 (P = 0.0146). Results indicated that both methods led to a satisfactory production of flies and egg inoculation provided an easier establishment.展开更多
The horn fly, Haematobia irritans, is a serious pest of cattle in North America. The control of horn flies has primarily relied on insecticides. However, the heavy use of insecticides has led to the development of ins...The horn fly, Haematobia irritans, is a serious pest of cattle in North America. The control of horn flies has primarily relied on insecticides. However, the heavy use of insecticides has led to the development of insecticide resistance in horn flies. Novel methods to control horn flies are greatly needed. Transgenic technology is an effective tool to genetically modify insects and may lead to novel methods of pest control based on genomic approaches. Here we report apiggyBac-mediated transformation of the horn fly via electroporation. Transformation with a DsRed fluorescent marker protein coding region was verified by PCR analysis of individual fly bodies and pupal cases and sequencing of PCR products. However, Southern blot analysis failed to indicate the DsRed gene was integrated into the horn fly genome. Thus, the electroporation protocol may have caused the DsRed gene to be integrated into bacterial symbionts of the horn fly.展开更多
As an economically important marine fish,the large yellow croaker Larimichthys crocea suffered from marine white spot disease caused by the ectoparasite Cryptocaryon irritans in recent years.This disease not only coul...As an economically important marine fish,the large yellow croaker Larimichthys crocea suffered from marine white spot disease caused by the ectoparasite Cryptocaryon irritans in recent years.This disease not only could result in physiological damage,but also lead to secondary bacterial invasion.Reports indicated some AMPs(antimicrobial peptides)were of antiparasitic activity to C.irritans.Hepcidin-like(Lc-HepL)was one of the significant differential expression genes excavated from the transcriptome following a challenge with C.irritans.In this study,we characterized this AMP’s bioactivity based on the levels of mRNA and protein.After challenged by C.irritans,qRT-PCR showed Lc-HepL was significantly upregulated in six tissues,including gill,muscle,liver,head kidney and spleen during theront infection,trophont falling off,and secondary bacterial invasion stages,which implicated a role Lc-HepL played in the immune defense against C.irritans and secondary bacterial infection.Recombinant Lc-HepL(rLc-HepL)was induced and purified successfully.rLc-HepL exhibited antibacterial activity to certain bacteria in a dose-and time-dependent manners.Anti-C.irritans activity was explored for the first time and found it could cause the theronts membrane rupture and contents leakage.These results provided the first evidence that Lc-HepL had strong antiparasitic activity against marine fish ectoparasites C.irritans theronts.Together,data indicated that Lc-HepL might be an important component in the innate immune system against C.irritans and has the potential to be employed in future drug development.展开更多
基金The National Natural Science Foundation of China under contract Nos 31372504,41176115 and 41476118
文摘Vibrio harveyi, known as a pathogenic bacterium caused severe secondary bacterial infections of the large yellow croaker Larimichthys crocea, was identified as an endosymbiont in the marine parasitic ciliate protozoan Cryptocaryon irritans. Meta 16 S sequencing method was used to identify the bacterial flora in C. irritans, and V.harveyi was isolated via culture-dependent method. Vibrio harveyi was observed in cytoplasm of C. irritans at the stage of tomont both by transmission electron microscopy and by Fluorescence in situ hybridization; no signal,however, was detected in nucleus area. The relationship between V. harveyi and C. irritans and the role of endosymbiotic V. harveyi in C. irritans merit further investigation.
文摘Several studies have required Haematobia irritans (L.) raising in laboratory. The present study assessed two methods of inoculating immature forms of H. irritans to obtain adults. In 2007, 15 Nellore steers (Bos indicus) (L.) were used for the collection of feces free of anthelmintic treatment and flies to produce for eggs and larva. For method I, 30 eggs were incubated in square filter paper (5 × 5 cm) and deposited on bovine feces (500 g) where they were kept until hatching and spontaneous penetration of larvae (L1) into the fecal mass. After 24 h, eggs were analyzed under a stereoscope microscope (40×) for the number of larvae that instinctively penetrated the feces. In method II, larvae were obtained only by natural egg hatching. At birth, 30 larvae were collected and individually inoculated, directly onto the fecal plate by employing a moistened brush. The tests were carried out at controlled temperature (28°C ± 2°C) and saturated humidity (80%) until the emergence of flies with both methods. The number of emerged flies was considered in the result. Using method I, 276 (76.7%) flies emerged from 360 inoculated eggs, while using method II, 283 (78.6%) flies emerged from 360 inoculated larvae. There was no significant difference (P = 0.7821) between methods for the number of flies;however, the proportion between males and females by means of larva inoculation was different from 1:1 (P = 0.0146). Results indicated that both methods led to a satisfactory production of flies and egg inoculation provided an easier establishment.
文摘The horn fly, Haematobia irritans, is a serious pest of cattle in North America. The control of horn flies has primarily relied on insecticides. However, the heavy use of insecticides has led to the development of insecticide resistance in horn flies. Novel methods to control horn flies are greatly needed. Transgenic technology is an effective tool to genetically modify insects and may lead to novel methods of pest control based on genomic approaches. Here we report apiggyBac-mediated transformation of the horn fly via electroporation. Transformation with a DsRed fluorescent marker protein coding region was verified by PCR analysis of individual fly bodies and pupal cases and sequencing of PCR products. However, Southern blot analysis failed to indicate the DsRed gene was integrated into the horn fly genome. Thus, the electroporation protocol may have caused the DsRed gene to be integrated into bacterial symbionts of the horn fly.
基金Foundation item:The National Key Research and Development Program of China under contract No.2018YFC1406302the Local Science and Technology Development Project Guide by the Central Government under contract No.2017L3019+2 种基金the Development Project Guide by the Central Government under contract No.2017L3019the Technical Innovation Platform for Large Yellow Croaker under contract No.XDHT2018143Athe Major Special Projects of Fujian Province under contract No.2016NZ0001.
文摘As an economically important marine fish,the large yellow croaker Larimichthys crocea suffered from marine white spot disease caused by the ectoparasite Cryptocaryon irritans in recent years.This disease not only could result in physiological damage,but also lead to secondary bacterial invasion.Reports indicated some AMPs(antimicrobial peptides)were of antiparasitic activity to C.irritans.Hepcidin-like(Lc-HepL)was one of the significant differential expression genes excavated from the transcriptome following a challenge with C.irritans.In this study,we characterized this AMP’s bioactivity based on the levels of mRNA and protein.After challenged by C.irritans,qRT-PCR showed Lc-HepL was significantly upregulated in six tissues,including gill,muscle,liver,head kidney and spleen during theront infection,trophont falling off,and secondary bacterial invasion stages,which implicated a role Lc-HepL played in the immune defense against C.irritans and secondary bacterial infection.Recombinant Lc-HepL(rLc-HepL)was induced and purified successfully.rLc-HepL exhibited antibacterial activity to certain bacteria in a dose-and time-dependent manners.Anti-C.irritans activity was explored for the first time and found it could cause the theronts membrane rupture and contents leakage.These results provided the first evidence that Lc-HepL had strong antiparasitic activity against marine fish ectoparasites C.irritans theronts.Together,data indicated that Lc-HepL might be an important component in the innate immune system against C.irritans and has the potential to be employed in future drug development.
