Sweepovirus is an important monopartite begomovirus that infects plants of the genus Ipomoea worldwide. Development of artificial infection methods for sweepovirus using agroinoculation is a highly efficient means of ...Sweepovirus is an important monopartite begomovirus that infects plants of the genus Ipomoea worldwide. Development of artificial infection methods for sweepovirus using agroinoculation is a highly efficient means of studying infectivity in sweet potato. Unlike other begomoviruses, it has proven difficult to infect sweet potato plants with sweepoviruses using infectious clones. A novel sweepovirus, called Sweet potato leaf curl virus-Jiangsu(SPLCV-JS), was recently identified in China. In addition, the infectivity of the SPLCV-JS clone has been demonstrated in Nicotiana benthamiana. Here we describe the agroinfection of the sweet potato cultivar Xushu 22 with the SPLCV-JS infectious clone using vacuum infiltration. Yellowing symptoms were observed in newly emerged leaves. Molecular analysis confirmed successful inoculation by the detection of viral DNA. A synergistic effect of SPLCV-JS and the heterologous betasatellite DNA-β of Tomato yellow leaf curl China virus isolate Y10(TYLCCNV-Y10) on enhanced symptom severity and viral DNA accumulation was confirmed. The development of a routine agroinoculation system in sweet potato with SPLCV-JS using vacuum infiltration should facilitate the molecular study of sweepovirus in this host and permit the evaluation of virus resistance of sweet potato plants in breeding programs.展开更多
RNA silencing is a conserved mechanism found ubiquitously in eukaryotic organisms.It has been used to regulate gene expression and development.In addition,RNA silencing serves as an important mechanism in plants' ...RNA silencing is a conserved mechanism found ubiquitously in eukaryotic organisms.It has been used to regulate gene expression and development.In addition,RNA silencing serves as an important mechanism in plants' defense against invasive nucleic acids,such as viruses,transposons,and transgenes.As a counter-defense,most plants,and some animal viruses,encode RNA silencing suppressors to interfere at one or several points of the silencing pathway.In this study,we showed that Pns12 of RGDV (Rice gall dwarf virus) exhibits silencing suppressor activity on the reporter green fluorescent protein in transgenic Nicotiana benthamiana line 16c.Pns12 of RGDV suppressed local silencing induced by sense RNA but had no effect on that induced by dsRNA.Expression of Pns12 also enhanced Potato virus X pathogenicity in N.benthamiana.Collectively,these results suggested that RGDV Pns12 functions as a virus suppressor of RNA silencing,which might target an upstream step of dsRNA formation in the RNA silencing pathway.Furthermore,we showed that Pns12 is localized mainly in the nucleus of N.benthamiana leaf cells.展开更多
基金supported by grants from the National High Technology Research and Development Program of China (2012AA101204)Shanghai Municipal Afforestation and City Appearance and Environmental Sanitation Administration (G102410, F132427)
文摘Sweepovirus is an important monopartite begomovirus that infects plants of the genus Ipomoea worldwide. Development of artificial infection methods for sweepovirus using agroinoculation is a highly efficient means of studying infectivity in sweet potato. Unlike other begomoviruses, it has proven difficult to infect sweet potato plants with sweepoviruses using infectious clones. A novel sweepovirus, called Sweet potato leaf curl virus-Jiangsu(SPLCV-JS), was recently identified in China. In addition, the infectivity of the SPLCV-JS clone has been demonstrated in Nicotiana benthamiana. Here we describe the agroinfection of the sweet potato cultivar Xushu 22 with the SPLCV-JS infectious clone using vacuum infiltration. Yellowing symptoms were observed in newly emerged leaves. Molecular analysis confirmed successful inoculation by the detection of viral DNA. A synergistic effect of SPLCV-JS and the heterologous betasatellite DNA-β of Tomato yellow leaf curl China virus isolate Y10(TYLCCNV-Y10) on enhanced symptom severity and viral DNA accumulation was confirmed. The development of a routine agroinoculation system in sweet potato with SPLCV-JS using vacuum infiltration should facilitate the molecular study of sweepovirus in this host and permit the evaluation of virus resistance of sweet potato plants in breeding programs.
基金supported by the National Basic Research Program of China(Grant No. 2010CB126203)the National Transgenic Major Program(Grant Nos. 2009ZX08009-044B and 2009ZX08001-018B)+2 种基金the National Natural Science Foundation of China(Grant No. 30970135)the Fujian Province Education Department(Grant No. JB08078)Specialized Research Fund for the Ministry of Agriculture(Grant No. nyhyzx07-051)
文摘RNA silencing is a conserved mechanism found ubiquitously in eukaryotic organisms.It has been used to regulate gene expression and development.In addition,RNA silencing serves as an important mechanism in plants' defense against invasive nucleic acids,such as viruses,transposons,and transgenes.As a counter-defense,most plants,and some animal viruses,encode RNA silencing suppressors to interfere at one or several points of the silencing pathway.In this study,we showed that Pns12 of RGDV (Rice gall dwarf virus) exhibits silencing suppressor activity on the reporter green fluorescent protein in transgenic Nicotiana benthamiana line 16c.Pns12 of RGDV suppressed local silencing induced by sense RNA but had no effect on that induced by dsRNA.Expression of Pns12 also enhanced Potato virus X pathogenicity in N.benthamiana.Collectively,these results suggested that RGDV Pns12 functions as a virus suppressor of RNA silencing,which might target an upstream step of dsRNA formation in the RNA silencing pathway.Furthermore,we showed that Pns12 is localized mainly in the nucleus of N.benthamiana leaf cells.
