The invention relates to a process for obtaining transgenic plants resistant to geminiviruses in a lasting manner. The transgene for expression in plant consists of a polynucleotide sequence derived from pathogenic virus. The sequence of the pathogen is derived for example from the sequence encoding the “protein associated with replication” (Rep) of the virus. The protein expressed by this sequence acts in trans as a dominant negative mutant, interfering with viral replication. In order to avoid the post-transcriptional gene silencing operated by the virus on sequence homologous transgenic, the nucleotide sequence derived from the pathogen is suitably mutagenized, in order to reduce the homology with the corresponding viral sequence, but leaving unchanged the protein sequence encoded. The plants thus transformed are not subject to gene silencing and resist in a stable manner to viral infection.
Inventors: Tavazza M., Noris E. Lucioli A., Accotto G.P., Tavazza R., Brunetti A.
Patent: Italian – International