Enhanced competitiveness of tomato bushy stunt virus defective interfering RNAs by segment duplication or nucleotide insertion.

Origin and Evolution of Defective Interfering RNAs of Tomato Bushy Stunt Virus

Host-specific generation and maintenance of Tomato bushy stunt virus defective interfering RNAs.

The accumulation of Tomato bushy stunt virus (TBSV) defective interfering RNAs (DIs) has been observed in several species of plants, but the involvement of host-specific processes and the functional role of DIs are still poorly understood. In this study, the accumulation of DIs was compared after several passages of TBSV through Nicotiana benthamiana and pepper (Capsicum annuum). As anticipated...

Broad-spectrum protection against tombusviruses elicited by defective interfering RNAs in transgenic plants.

We have designed a DNA cassette to transcribe defective interfering (DI) RNAs of tomato bushy stunt virus (TBSV) and have investigated their potential to protect transgenic Nicotiana benthamiana plants from tombusvirus infections. To produce RNAs with authentic 5' and 3' termini identical to those of the native B10 DI RNA, the DI RNA sequences were flanked by ribozymes (RzDI). When RzDI RNAs tr...

Partial purification and characterization of Cucumber necrosis virus and Tomato bushy stunt virus RNA-dependent RNA polymerases: similarities and differences in template usage between tombusvirus and carmovirus RNA-dependent RNA polymerases.

Tombusviruses are small, plus-sense, single-stranded RNA viruses of plants. RNA-dependent RNA polymerases (RdRp) of two tombusviruses, Tomato bushy stunt virus (TBSV) and Cucumber necrosis virus (CNV), have been partially purified from infected Nicotiana benthamiana plants. The obtained RdRp complexes are capable of de novo initiation of complementary RNA synthesis using either plus- or minus-s...

Nonhomologous RNA recombination in tombusviruses: generation and evolution of defective interfering RNAs by stepwise deletions.

We used a protoplast system to study the mechanisms involved in the generation and evolution of defective interfering (DI) RNAs of tomato bushy stunt tombusvirus (TBSV). Synthetic transcripts corresponding to different naturally occurring TBSV DI RNAs, or to various artificially constructed TBSV defective RNAs, were analyzed. The relative levels of competitiveness of different DI RNAs were dete...