分别以接种感染芜菁花叶病毒(TuMV)和健康对照的青菜苏州青品种(Brassica chinensis L. cv.Suzhou)和芥菜温州芥菜品种(B.juncea L. cv.Wenzhou)叶片为材料提取完整叶绿体,用胰蛋白酶消除其表面蛋白后,抽提总蛋白,经SDS-PAGE电泳和Weste...分别以接种感染芜菁花叶病毒(TuMV)和健康对照的青菜苏州青品种(Brassica chinensis L. cv.Suzhou)和芥菜温州芥菜品种(B.juncea L. cv.Wenzhou)叶片为材料提取完整叶绿体,用胰蛋白酶消除其表面蛋白后,抽提总蛋白,经SDS-PAGE电泳和Western blot检测,发现TuMV的外壳蛋白(CP)存在于感病寄主的叶绿体中。免疫金标记电镜实验显示TuMV-CP定位在感病青菜和芥菜的细胞质和叶绿体中。对两种寄主植物叶片的叶绿素荧光动力学参数测定结果显示,青菜、芥菜的Fv/Fo、Fv/Fm、φPSII、qp值都有不同程度的降低,qN值增大。实验结果表明TuMV侵染后在寄主细胞叶绿体中积累的CP,抑制了光系统II(PS II)的光化学活性,这可能是影响寄主植物光合作用的一个重要原因。展开更多
Wheat yellow dwarf disease(BYD),caused by different species of barley/cereal yellow dwarf viruses(B/CYDVs),is one of the most serious cereal diseases in China and the Czech Republic.Because genetic diversity of the vi...Wheat yellow dwarf disease(BYD),caused by different species of barley/cereal yellow dwarf viruses(B/CYDVs),is one of the most serious cereal diseases in China and the Czech Republic.Because genetic diversity of the virus directly influences disease epidemiology,the molecular diversity and population structure of 24 Chinese isolates and 16 the Czech Republic isolates of BYDV-PAV from different regions in two countries were analyzed by sequencing their coat protein(CP)and readthrough protein(RTP)domain(RTD)genes and comparing the sequences with six CP and 16 RTP sequences of BYDVPAV isolates from the NCBI database based on nucleotide identity position,phylogenetic analysis and nucleotide diversity.Nucleotide identities between the Chinese and the Czech Republic isolates for the CP were 76.6–99.4%,73.9–89.1%for RTD(ORF5),respectively.The Chinese and the other country isolates showed 74.7–99.2%nucleotide identity for RTP(ORF3+ORF5).Phylogenetic analysis of CP sequences showed that 20 Chinese isolates clustered in the same clade,but the other four Chinese isolates clustered in another clade with the isolates from the Czech Republic and other counties.The population of BYDV-PAV in China had greater nucleotide variability and was more divergent than that in the Czech Republic.Geographical and ecological factors but not hosts might contribute to the population differences in the two countries.展开更多
Imperata yellow mottle virus (IYMV, Sobemovirus) was first described in 2008 in the south-western region of Burkina Faso (West Africa). The genetic diversity of IYMV was not documented up to day. In this study, the va...Imperata yellow mottle virus (IYMV, Sobemovirus) was first described in 2008 in the south-western region of Burkina Faso (West Africa). The genetic diversity of IYMV was not documented up to day. In this study, the variability of CP of IYMV was evaluated through the molecular characterization of 38 isolates collected in the western part of Burkina Faso. Comparison of sequences of these new isolates and one IYMV sequence available in GenBank revealed that the average nucleotide diversity was low. The ratio of non-synonymous over synonymous nucleotide substitutions per site was low, indicating a CP diversification under strong purifying selection. Despite of the low nucleotide diversity, phylogenetic analyses revealed segregation of IYMV isolates into six major clades. There was no correlation of phylogenetic grouping of isolates based on geographical location. This is the first study of the genetic diversity of IYMV.展开更多
文摘分别以接种感染芜菁花叶病毒(TuMV)和健康对照的青菜苏州青品种(Brassica chinensis L. cv.Suzhou)和芥菜温州芥菜品种(B.juncea L. cv.Wenzhou)叶片为材料提取完整叶绿体,用胰蛋白酶消除其表面蛋白后,抽提总蛋白,经SDS-PAGE电泳和Western blot检测,发现TuMV的外壳蛋白(CP)存在于感病寄主的叶绿体中。免疫金标记电镜实验显示TuMV-CP定位在感病青菜和芥菜的细胞质和叶绿体中。对两种寄主植物叶片的叶绿素荧光动力学参数测定结果显示,青菜、芥菜的Fv/Fo、Fv/Fm、φPSII、qp值都有不同程度的降低,qN值增大。实验结果表明TuMV侵染后在寄主细胞叶绿体中积累的CP,抑制了光系统II(PS II)的光化学活性,这可能是影响寄主植物光合作用的一个重要原因。
基金This research was supported by the Inter-Governmental S&T Cooperation Project of China(2016YFE0131000)the Research Program of the Ministry of Education,Youth and Sports of the Czech Republic(LTACH-17010).
文摘Wheat yellow dwarf disease(BYD),caused by different species of barley/cereal yellow dwarf viruses(B/CYDVs),is one of the most serious cereal diseases in China and the Czech Republic.Because genetic diversity of the virus directly influences disease epidemiology,the molecular diversity and population structure of 24 Chinese isolates and 16 the Czech Republic isolates of BYDV-PAV from different regions in two countries were analyzed by sequencing their coat protein(CP)and readthrough protein(RTP)domain(RTD)genes and comparing the sequences with six CP and 16 RTP sequences of BYDVPAV isolates from the NCBI database based on nucleotide identity position,phylogenetic analysis and nucleotide diversity.Nucleotide identities between the Chinese and the Czech Republic isolates for the CP were 76.6–99.4%,73.9–89.1%for RTD(ORF5),respectively.The Chinese and the other country isolates showed 74.7–99.2%nucleotide identity for RTP(ORF3+ORF5).Phylogenetic analysis of CP sequences showed that 20 Chinese isolates clustered in the same clade,but the other four Chinese isolates clustered in another clade with the isolates from the Czech Republic and other counties.The population of BYDV-PAV in China had greater nucleotide variability and was more divergent than that in the Czech Republic.Geographical and ecological factors but not hosts might contribute to the population differences in the two countries.
文摘Imperata yellow mottle virus (IYMV, Sobemovirus) was first described in 2008 in the south-western region of Burkina Faso (West Africa). The genetic diversity of IYMV was not documented up to day. In this study, the variability of CP of IYMV was evaluated through the molecular characterization of 38 isolates collected in the western part of Burkina Faso. Comparison of sequences of these new isolates and one IYMV sequence available in GenBank revealed that the average nucleotide diversity was low. The ratio of non-synonymous over synonymous nucleotide substitutions per site was low, indicating a CP diversification under strong purifying selection. Despite of the low nucleotide diversity, phylogenetic analyses revealed segregation of IYMV isolates into six major clades. There was no correlation of phylogenetic grouping of isolates based on geographical location. This is the first study of the genetic diversity of IYMV.