Cucumber mosaic virus（CMV） can infect a wide range of host species. For the lacking of CMV resistant varieties of tomato, RNA interference（RNAi） can be used as a fast and effective method for the generation of tra...Cucumber mosaic virus（CMV） can infect a wide range of host species. For the lacking of CMV resistant varieties of tomato, RNA interference（RNAi） can be used as a fast and effective method for the generation of transgenic resistant varieties. In this current study, five intron-spliced hairpin RNA（ihp RNA） plant expression vectors aimed at five genes of CMV have been constructed. Transgenic tomatoes were obtained by Agrobacterium tumefaciens-mediated transformation with expression vectors. Highly resistant generations of transgenic plants were employed as rootstocks and grafted onto non-transgenic tomatoes that resulted in the successful transfer of resistance to the scions. Using a novel method of plant cuttings for rootstock propagation, we obtained large quantities of disease-resistant material. Further, this method produces scions that can remain undetectable for transgenic resistance marker genes that may provide novel approaches to evade collective concerns about genetically-modified organism（GMO） biosafety.展开更多
Cucumber mosaic virus （CMV）, a positive-sense single-stranded RNA virus, has a very wide host range and a worldwide distribution, and is considered as one of the most virulent plant viruses in the world. The CMV gen...Cucumber mosaic virus （CMV）, a positive-sense single-stranded RNA virus, has a very wide host range and a worldwide distribution, and is considered as one of the most virulent plant viruses in the world. The CMV gene sequences, gene products, and their interaction with hosts have been extensively reported since it was discovered in 1916. With the development of high-throughput sequencing and proteomics, great progress has been made in the molecular mechanism of CMV pathogenesis in recent years. In this review, we introduce CMV-encoded proteins, CMV-related satellite RNAs and the roles of host factors in the pathogenesis of CMV, to provide a theoretical basis for future study of CMV.展开更多
RNA silencing has been shown to function in the plant antivirus defense response,leading to viral RNA degradation induced by vsiRNA-containing RISC cleavage activity.Cucumber mosaic virus(CMV) 3′UTR sequences share a...RNA silencing has been shown to function in the plant antivirus defense response,leading to viral RNA degradation induced by vsiRNA-containing RISC cleavage activity.Cucumber mosaic virus(CMV) 3′UTR sequences share a high conservation of nucleotide sequence and secondary structures that are important for CMV replication.Here,in an attempt to simultaneously target the multiple genomic and subgenomic RNAs of CMV for degradation,CMV 3′UTR were used to design hairpin RNA(hpRNA) to transform tobacco(Xanthi.nc) so as to constitutively produce viral siRNAs.Most of the transgenic plants expressing CMV Q strain(Q-CMV,subgroup Ⅱ strain) RNA3 3′UTR-derived hpRNA showed de-layed resistance to Q-CMV infection and exhibited recovery phenotypes.Compared with Q-CMV-in-oculated leaves,the upper leaves showed weak or no disease symptoms and a reduced accumulation level of viral RNAs.Together with transient assays,our results indicate that the 3′UTR-derived siRNAs were biologically active in targeting viral RNA for degradation.Recovery resistance in transgenic plants was also observed against subgroup IB strain SD-CMV infection,indicating a broad-spectrum anti-CMV effect of the 3′UTR-based antiviral silencing.Northern blot assays indicated that there was no strong correlation between the degree of resistance and the accumulation level of 3′UTR-derived siRNAs,suggesting that to target a highly structured RNA,such as the CMV 3′UTR,the quantity of siRNAs may not be the only determinant of silencing efficiency.Target RNA secondary structures may also affect target accessibility,siRNA-containing RISC-target recognition and the consequent antiviral effect.展开更多
The synthesized full-length cDNA to CMV satellite RNA-1 was integrated into plant expression vector RoKII with a CaMV 35S promoter. Infected by Agrobacterium tumefaciens harbouring the recombinant plasmid. The tobacco...The synthesized full-length cDNA to CMV satellite RNA-1 was integrated into plant expression vector RoKII with a CaMV 35S promoter. Infected by Agrobacterium tumefaciens harbouring the recombinant plasmid. The tobacco leaf discs (the G-140 variety which is widely cultivated in China) were regenerated into plants. After being inoculated with virulent strain CMV, most of the transgenic plants expressed satellite RNA at high levels and developed a much milder symptom than the untransformed ones.Basically in accordance with Mendel’s law of segregation, the novel tobacco pure line engineered with viral resistance was screened out. The secondary generation transgenic plants still maintained high level satellite RNA expression and the resistance to CMV.展开更多
基金supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China(20134320120013)the Natural Science Foundation of Hunan Province of China(14JJ3095)
文摘Cucumber mosaic virus（CMV） can infect a wide range of host species. For the lacking of CMV resistant varieties of tomato, RNA interference（RNAi） can be used as a fast and effective method for the generation of transgenic resistant varieties. In this current study, five intron-spliced hairpin RNA（ihp RNA） plant expression vectors aimed at five genes of CMV have been constructed. Transgenic tomatoes were obtained by Agrobacterium tumefaciens-mediated transformation with expression vectors. Highly resistant generations of transgenic plants were employed as rootstocks and grafted onto non-transgenic tomatoes that resulted in the successful transfer of resistance to the scions. Using a novel method of plant cuttings for rootstock propagation, we obtained large quantities of disease-resistant material. Further, this method produces scions that can remain undetectable for transgenic resistance marker genes that may provide novel approaches to evade collective concerns about genetically-modified organism（GMO） biosafety.
基金Supported by the Special Fund for Basic Scientific Research of Chinese Academy of Inspection and Quarantine(2017JK035)
文摘Cucumber mosaic virus （CMV）, a positive-sense single-stranded RNA virus, has a very wide host range and a worldwide distribution, and is considered as one of the most virulent plant viruses in the world. The CMV gene sequences, gene products, and their interaction with hosts have been extensively reported since it was discovered in 1916. With the development of high-throughput sequencing and proteomics, great progress has been made in the molecular mechanism of CMV pathogenesis in recent years. In this review, we introduce CMV-encoded proteins, CMV-related satellite RNAs and the roles of host factors in the pathogenesis of CMV, to provide a theoretical basis for future study of CMV.
基金the State Basic Research Development Program of China (Grant No. 2006CB101906)National Natural Science Foundation of China (Grant No. 30530500)
文摘RNA silencing has been shown to function in the plant antivirus defense response,leading to viral RNA degradation induced by vsiRNA-containing RISC cleavage activity.Cucumber mosaic virus(CMV) 3′UTR sequences share a high conservation of nucleotide sequence and secondary structures that are important for CMV replication.Here,in an attempt to simultaneously target the multiple genomic and subgenomic RNAs of CMV for degradation,CMV 3′UTR were used to design hairpin RNA(hpRNA) to transform tobacco(Xanthi.nc) so as to constitutively produce viral siRNAs.Most of the transgenic plants expressing CMV Q strain(Q-CMV,subgroup Ⅱ strain) RNA3 3′UTR-derived hpRNA showed de-layed resistance to Q-CMV infection and exhibited recovery phenotypes.Compared with Q-CMV-in-oculated leaves,the upper leaves showed weak or no disease symptoms and a reduced accumulation level of viral RNAs.Together with transient assays,our results indicate that the 3′UTR-derived siRNAs were biologically active in targeting viral RNA for degradation.Recovery resistance in transgenic plants was also observed against subgroup IB strain SD-CMV infection,indicating a broad-spectrum anti-CMV effect of the 3′UTR-based antiviral silencing.Northern blot assays indicated that there was no strong correlation between the degree of resistance and the accumulation level of 3′UTR-derived siRNAs,suggesting that to target a highly structured RNA,such as the CMV 3′UTR,the quantity of siRNAs may not be the only determinant of silencing efficiency.Target RNA secondary structures may also affect target accessibility,siRNA-containing RISC-target recognition and the consequent antiviral effect.
文摘The synthesized full-length cDNA to CMV satellite RNA-1 was integrated into plant expression vector RoKII with a CaMV 35S promoter. Infected by Agrobacterium tumefaciens harbouring the recombinant plasmid. The tobacco leaf discs (the G-140 variety which is widely cultivated in China) were regenerated into plants. After being inoculated with virulent strain CMV, most of the transgenic plants expressed satellite RNA at high levels and developed a much milder symptom than the untransformed ones.Basically in accordance with Mendel’s law of segregation, the novel tobacco pure line engineered with viral resistance was screened out. The secondary generation transgenic plants still maintained high level satellite RNA expression and the resistance to CMV.
