The monopartite Begomovirus (Geminiviridae) Tomato yellow leaf curl Sardinia virus (TYLCSV) has a capsid protein (CP) indispensable for plant infection and vector transmission. Amino acids (aa) between Q129 and D152 are critical for insect transmissibility. In this study, two previously described non-transmissible (NT) mutants, one with a Q129P and Q134H (PNHD) mutation, another with with a further D152E change (PNHE), plus a new mutant with a single N130D change (QDQD) were considered for their relationship with whiteflies, in comparison with the wild-type virus (QNQD). Using quantitative dot-blot hybridization, their retention kinetic in whiteflies was analysed following feeding on infected plants. Mutant QDQD, forming unstable and anomalous virions, was hardly detectable in insects even at the end of the acquisition. PNHD was acquired and circulated in both B. tabaci and T. vaporariorum for at least 7 days, while the PNHE mutant circulated in B. tabaci only. To see if NT mutants interfered with the transmission of the wt QNQD virus, pre-aquisitions on NT mutants were performed before feeding on the wt virus. The transmission of the wt virus was inhibited by pre-feeding on the PNHE mutant, but not on the other. Immunolocalisation analysis of the viral CP will be presented on B. tabaci previously exposed to plants infected by the different mutants.
Characterisation of non-transmissible mutants of TYLCSV in the whitefly vector Bemisia tabaci.
Noris E;Accotto;G P;Marian D;Masenga V;Caciagli;
2008
Abstract
The monopartite Begomovirus (Geminiviridae) Tomato yellow leaf curl Sardinia virus (TYLCSV) has a capsid protein (CP) indispensable for plant infection and vector transmission. Amino acids (aa) between Q129 and D152 are critical for insect transmissibility. In this study, two previously described non-transmissible (NT) mutants, one with a Q129P and Q134H (PNHD) mutation, another with with a further D152E change (PNHE), plus a new mutant with a single N130D change (QDQD) were considered for their relationship with whiteflies, in comparison with the wild-type virus (QNQD). Using quantitative dot-blot hybridization, their retention kinetic in whiteflies was analysed following feeding on infected plants. Mutant QDQD, forming unstable and anomalous virions, was hardly detectable in insects even at the end of the acquisition. PNHD was acquired and circulated in both B. tabaci and T. vaporariorum for at least 7 days, while the PNHE mutant circulated in B. tabaci only. To see if NT mutants interfered with the transmission of the wt QNQD virus, pre-aquisitions on NT mutants were performed before feeding on the wt virus. The transmission of the wt virus was inhibited by pre-feeding on the PNHE mutant, but not on the other. Immunolocalisation analysis of the viral CP will be presented on B. tabaci previously exposed to plants infected by the different mutants.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
