【目的】Arsenophonus、Wolbachia、Spiroplasma和Cardinium是广泛分布于昆虫体内的次生共生菌,能对寄主昆虫的生殖和发育生理产生影响,明确不同地理种群褐飞虱体内4种共生菌的感染和系统发育关系可为利用共生菌防治害虫提供技术依据。...【目的】Arsenophonus、Wolbachia、Spiroplasma和Cardinium是广泛分布于昆虫体内的次生共生菌,能对寄主昆虫的生殖和发育生理产生影响,明确不同地理种群褐飞虱体内4种共生菌的感染和系统发育关系可为利用共生菌防治害虫提供技术依据。【方法】利用Arsenophonus特异性23S rRNA基因引物,Wolbachia、Spiroplasma和Cardinium各自的16S rRNA基因引物PCR检测广西10个地市、海南海口及上海、江苏南京、湖南长沙共14个地理种群褐飞虱雌、雄虫体内共生菌感染情况,并对扩增到的基因片段进行测序、构建系统发育树。【结果】不同地区2014年和2015年褐飞虱体内Arsenophonus感染率最高的分别为河池种群(30%)和长沙种群(20%)、PWolbachia感染率最高为河池种群(20%)和南京种群(30%),而Spiroplasma和Cardinium在褐飞虱各种群内均未检测到。序列比对和发育分析表明,褐飞虱体内Arsenophonus与同翅目昆虫白蜡虫Ericerus pela Chavannes体内感染的该菌关系最近;而感染Wolbachia菌的系统发育分析表明,除海南种群有一个个体感染Wolbachia菌A群外,其余种群感染的全部为B群;同时在所有感染两类共生菌的个体中并未发现共感染现象。【结论】不同地理种群褐飞虱感染Arsenophonus和Wolbachia两类共生菌的感染率并不一致;总体上褐飞虱雌虫Wolbachia感染率要高于雄虫,褐飞虱体内感染的两类共生菌与其它昆虫体内的共生菌序列高度一致或类似,且在所有检测的地理种群中均未发现有Spiroplasma和Cardinium感染。展开更多
Stubborn disease of citrus is one of the main causes of quality deterioration of citrus fruits in Egypt. The early detection and the molecular characterization of the causal agent are vital for revealing its real dist...Stubborn disease of citrus is one of the main causes of quality deterioration of citrus fruits in Egypt. The early detection and the molecular characterization of the causal agent are vital for revealing its real distribution and for management. In 2011, several samples were collected at different times of the year from stubborn suspected symptomatic trees within the main citrus growing area in Egypt, the Nile-delta region. After culturing the causal agent on artificial LD8 media from the field fresh samples, two new and improved methods of biological indexing were set up and compared with the traditional method in order to increase the detection efficiency by increasing the greenhouse transmission rate;which reached 85% with the new inverse inoculation method. Different PCR primer pairs were evaluated for their detection efficiency of the Egyptian Isolates of Spiroplasma citri and the most specific primer pair for these local isolates was determined. Improving the efficiency of biological indexing, along with determining the most specific and efficient PCR primer pair for the detection, will enhance and facilitate the citrus certification programs in Egypt, making them better tools for the early detection of stubborn disease. Furthermore obtained Egyptian isolates were characterized molecularly by the analysis of the obtained sequences showing close relationship with the Moroccan strain (GII3).展开更多
Tsetse flies(Glossina spp.)can vector the parasites(Trypanosoma spp.)that cause the socioeconomically devastating neglected tropical diseases human and animal African trypanosomoses.In addition to this parasite,tsetse...Tsetse flies(Glossina spp.)can vector the parasites(Trypanosoma spp.)that cause the socioeconomically devastating neglected tropical diseases human and animal African trypanosomoses.In addition to this parasite,tsetse can harbor four genera of endosymbiotic bacteria,including Wigglesworthia,Sodalis,Wolbachia,and Spiroplasma,which are functionally crucial for the fly's physiological homeostasis and/or are potentially useful for the development of disease control strategies.Recent discoveries indicate that Spiroplasma infection negatively impacts tsetse fecundity.Conversely,housing the bacterium can benefit its fly host by making it unusually refractory to infection with parasitic African trypanosomes.In this study,we assessed the physiological impact of Spiroplasma infection on a laboratory colony of Glossina fuscipes fuscipes(Gff).For this purpose,two distinct Gff colonies were established:a Spi–colony that harbors a low Spiroplasma infection prevalence and a Spi+colony that harbors a high Spiroplasma infection prevalence.Fitness parameters for both colonies revealed no significant differences in the length of larval development,adult eclosion rate,and flight propensity.However,flies from the Spi+colony presented with lower fecundity and higher overall mortality than did individuals from the Spi–colony.Furthermore,males from the Spi–colony exhibited a competitive mating advantage over their Spi+counterparts in a field cage setting.These findings have potential implications for the improvement of mass-rearing of Gff for sterile insect technique(SIT)applications.展开更多
Sterile Insect Technique(SIT)has proven effective to reduce tsetse population density in large infected areas where animal African trypanosomosis(AAT)and human African trypanosomiasis(HAT)elimination was difficult to ...Sterile Insect Technique(SIT)has proven effective to reduce tsetse population density in large infected areas where animal African trypanosomosis(AAT)and human African trypanosomiasis(HAT)elimination was difficult to achieve.However,the decrease in mass production of insectary-reared tsetse and the limited but incomplete knowledge on symbiont–trypanosome interaction over time,impede large-scale use of SIT.We investigated the spatiotemporal changes in symbiont prevalence and symbiont–trypanosome interactions in wild tsetse of Sora-Mboum AAT focus in northern Cameroon,collected in 2019 and 2020,to provide insights into the mass production of refractory tsetse.Spiroplasma spp.,Sodalis glossinidius and trypanosomes were screened with PCR.G.tachinoides was the most abundant Glossina species found in Sora-Mboum focus.Symbiont prevalences in G.tachinoides were higher in 2019 compared to 2020,from 67.6%to 53.5%for Spiroplasma spp.and from 28.8%to 8.1%for S.glossinidius.These symbionts were also found at higher prevalence in flies from Mouhoun HAT focus in Burkina Faso.Four trypanosome taxa(Trypanosoma congolense forest type,T.congolense savannah type,T.brucei s.l.,and T.vivax)were found in Sora-Mboum focus and Mouhoun focus,though at lower prevalence in Mouhoun.The presence of Spiroplasma spp.in adult tsetse was negatively associated with that of trypanosomes.Our study highlights the potential of Spiroplasma spp.as a good paratransgenesis candidate to enhance SIT application.This symbiont is naturally found in high proportions of tsetse and could prevent factory flies from acquiring and transmitting trypanosomes during their lifespan when released for population density control.展开更多
Wolbachia and Spiroplasma are intracellular bacteria that are of great interest to entomologists,because of their ability to alter insect host biology in multiple ways.In the spider mite Tetranychus truncatus,co-infec...Wolbachia and Spiroplasma are intracellular bacteria that are of great interest to entomologists,because of their ability to alter insect host biology in multiple ways.In the spider mite Tetranychus truncatus,co-infection of Wolbachia and Spiroplasma can induce cytoplasmic incompatibility(CI)and fitness costs;however,lttle is known about the effect of co-infection at the genetic level and the molecular mechanisms underlying CI.In this study,we explored the influence of the two symbionts on male mite host fitness and used RNA sequencing to generate the transcriptomes of T truncatus with four different types of infection.In total,we found symbiont-infected lines had a higher hatch proportion than the uninfected line,and the development time of the uninfected line was longer than that of the other lines.Co-infection changed the expression of many genes related to digestion detoxification,reproduction,immunity and oxidation reduction.Our results indicate that co-infection of Wolbachia and Spiroplasma confers multiple effects on their hosts,and helps iluminate the complex interactions between endosymbionts and arthropods.展开更多
The strain CCH, isolated from the surface of the plant flower in China, is a wall- less,helical prokaryote which passes through a microfilter 0. 22 μm in diameter. Cholesterol isrequired for its growth. The strain CC...The strain CCH, isolated from the surface of the plant flower in China, is a wall- less,helical prokaryote which passes through a microfilter 0. 22 μm in diameter. Cholesterol isrequired for its growth. The strain CCH could metabolize glucose, fructose, maltose, treha-lose and arginine, but not urea. Its electrophoresis pattern of cell proteins is distinct fromthat of other spiroplasmas. The guanine-plus-cyrosine content of its DNA determined bymelting temperature is 29. 15 mol%. No relation with any known spiroplasmas was found inenzyme-linked immunosorbent assay and deformation tests. According to these results, thestrain CCH is referred to a new species in the genus of Spiroplasma or the representative ofa new spiroplasma group.展开更多
文摘【目的】Arsenophonus、Wolbachia、Spiroplasma和Cardinium是广泛分布于昆虫体内的次生共生菌,能对寄主昆虫的生殖和发育生理产生影响,明确不同地理种群褐飞虱体内4种共生菌的感染和系统发育关系可为利用共生菌防治害虫提供技术依据。【方法】利用Arsenophonus特异性23S rRNA基因引物,Wolbachia、Spiroplasma和Cardinium各自的16S rRNA基因引物PCR检测广西10个地市、海南海口及上海、江苏南京、湖南长沙共14个地理种群褐飞虱雌、雄虫体内共生菌感染情况,并对扩增到的基因片段进行测序、构建系统发育树。【结果】不同地区2014年和2015年褐飞虱体内Arsenophonus感染率最高的分别为河池种群(30%)和长沙种群(20%)、PWolbachia感染率最高为河池种群(20%)和南京种群(30%),而Spiroplasma和Cardinium在褐飞虱各种群内均未检测到。序列比对和发育分析表明,褐飞虱体内Arsenophonus与同翅目昆虫白蜡虫Ericerus pela Chavannes体内感染的该菌关系最近;而感染Wolbachia菌的系统发育分析表明,除海南种群有一个个体感染Wolbachia菌A群外,其余种群感染的全部为B群;同时在所有感染两类共生菌的个体中并未发现共感染现象。【结论】不同地理种群褐飞虱感染Arsenophonus和Wolbachia两类共生菌的感染率并不一致;总体上褐飞虱雌虫Wolbachia感染率要高于雄虫,褐飞虱体内感染的两类共生菌与其它昆虫体内的共生菌序列高度一致或类似,且在所有检测的地理种群中均未发现有Spiroplasma和Cardinium感染。
文摘Stubborn disease of citrus is one of the main causes of quality deterioration of citrus fruits in Egypt. The early detection and the molecular characterization of the causal agent are vital for revealing its real distribution and for management. In 2011, several samples were collected at different times of the year from stubborn suspected symptomatic trees within the main citrus growing area in Egypt, the Nile-delta region. After culturing the causal agent on artificial LD8 media from the field fresh samples, two new and improved methods of biological indexing were set up and compared with the traditional method in order to increase the detection efficiency by increasing the greenhouse transmission rate;which reached 85% with the new inverse inoculation method. Different PCR primer pairs were evaluated for their detection efficiency of the Egyptian Isolates of Spiroplasma citri and the most specific primer pair for these local isolates was determined. Improving the efficiency of biological indexing, along with determining the most specific and efficient PCR primer pair for the detection, will enhance and facilitate the citrus certification programs in Egypt, making them better tools for the early detection of stubborn disease. Furthermore obtained Egyptian isolates were characterized molecularly by the analysis of the obtained sequences showing close relationship with the Moroccan strain (GII3).
文摘Tsetse flies(Glossina spp.)can vector the parasites(Trypanosoma spp.)that cause the socioeconomically devastating neglected tropical diseases human and animal African trypanosomoses.In addition to this parasite,tsetse can harbor four genera of endosymbiotic bacteria,including Wigglesworthia,Sodalis,Wolbachia,and Spiroplasma,which are functionally crucial for the fly's physiological homeostasis and/or are potentially useful for the development of disease control strategies.Recent discoveries indicate that Spiroplasma infection negatively impacts tsetse fecundity.Conversely,housing the bacterium can benefit its fly host by making it unusually refractory to infection with parasitic African trypanosomes.In this study,we assessed the physiological impact of Spiroplasma infection on a laboratory colony of Glossina fuscipes fuscipes(Gff).For this purpose,two distinct Gff colonies were established:a Spi–colony that harbors a low Spiroplasma infection prevalence and a Spi+colony that harbors a high Spiroplasma infection prevalence.Fitness parameters for both colonies revealed no significant differences in the length of larval development,adult eclosion rate,and flight propensity.However,flies from the Spi+colony presented with lower fecundity and higher overall mortality than did individuals from the Spi–colony.Furthermore,males from the Spi–colony exhibited a competitive mating advantage over their Spi+counterparts in a field cage setting.These findings have potential implications for the improvement of mass-rearing of Gff for sterile insect technique(SIT)applications.
基金financial support from IAEA CRP D42017(Improvement of Colony Management in insect Mass-Rearing for SIT Applications)Contract Number:22636,from the Medical Research Council of the UK through the Global Challenges Research Fund(grant number MR/P027873/1)Laboratory facilities from the Centre for Research in Infectious Diseases(CRID),Yaoundé,Cameroon.
文摘Sterile Insect Technique(SIT)has proven effective to reduce tsetse population density in large infected areas where animal African trypanosomosis(AAT)and human African trypanosomiasis(HAT)elimination was difficult to achieve.However,the decrease in mass production of insectary-reared tsetse and the limited but incomplete knowledge on symbiont–trypanosome interaction over time,impede large-scale use of SIT.We investigated the spatiotemporal changes in symbiont prevalence and symbiont–trypanosome interactions in wild tsetse of Sora-Mboum AAT focus in northern Cameroon,collected in 2019 and 2020,to provide insights into the mass production of refractory tsetse.Spiroplasma spp.,Sodalis glossinidius and trypanosomes were screened with PCR.G.tachinoides was the most abundant Glossina species found in Sora-Mboum focus.Symbiont prevalences in G.tachinoides were higher in 2019 compared to 2020,from 67.6%to 53.5%for Spiroplasma spp.and from 28.8%to 8.1%for S.glossinidius.These symbionts were also found at higher prevalence in flies from Mouhoun HAT focus in Burkina Faso.Four trypanosome taxa(Trypanosoma congolense forest type,T.congolense savannah type,T.brucei s.l.,and T.vivax)were found in Sora-Mboum focus and Mouhoun focus,though at lower prevalence in Mouhoun.The presence of Spiroplasma spp.in adult tsetse was negatively associated with that of trypanosomes.Our study highlights the potential of Spiroplasma spp.as a good paratransgenesis candidate to enhance SIT application.This symbiont is naturally found in high proportions of tsetse and could prevent factory flies from acquiring and transmitting trypanosomes during their lifespan when released for population density control.
基金supported in part by a grant-in-aid for Scientific Research(31672035,31871976)from the National Natural Science Foundation of China.
文摘Wolbachia and Spiroplasma are intracellular bacteria that are of great interest to entomologists,because of their ability to alter insect host biology in multiple ways.In the spider mite Tetranychus truncatus,co-infection of Wolbachia and Spiroplasma can induce cytoplasmic incompatibility(CI)and fitness costs;however,lttle is known about the effect of co-infection at the genetic level and the molecular mechanisms underlying CI.In this study,we explored the influence of the two symbionts on male mite host fitness and used RNA sequencing to generate the transcriptomes of T truncatus with four different types of infection.In total,we found symbiont-infected lines had a higher hatch proportion than the uninfected line,and the development time of the uninfected line was longer than that of the other lines.Co-infection changed the expression of many genes related to digestion detoxification,reproduction,immunity and oxidation reduction.Our results indicate that co-infection of Wolbachia and Spiroplasma confers multiple effects on their hosts,and helps iluminate the complex interactions between endosymbionts and arthropods.
基金Project supported by the National Natural Science Foundation of China. Part of this research was done in Rutgers University, U.S.A.
文摘The strain CCH, isolated from the surface of the plant flower in China, is a wall- less,helical prokaryote which passes through a microfilter 0. 22 μm in diameter. Cholesterol isrequired for its growth. The strain CCH could metabolize glucose, fructose, maltose, treha-lose and arginine, but not urea. Its electrophoresis pattern of cell proteins is distinct fromthat of other spiroplasmas. The guanine-plus-cyrosine content of its DNA determined bymelting temperature is 29. 15 mol%. No relation with any known spiroplasmas was found inenzyme-linked immunosorbent assay and deformation tests. According to these results, thestrain CCH is referred to a new species in the genus of Spiroplasma or the representative ofa new spiroplasma group.
