DE-NOVO METHYLATION AND CO-SUPPRESSION INDUCED BY A CYTOPLASMICALLY REPLICATING PLANT RNA VIRUS

Citation
Al. Jones et al., DE-NOVO METHYLATION AND CO-SUPPRESSION INDUCED BY A CYTOPLASMICALLY REPLICATING PLANT RNA VIRUS, EMBO journal (Print), 17(21), 1998, pp. 6385-6393
Citations number
49
Categorie Soggetti
Biology,"Cell Biology
Journal title
ISSN journal
02614189
Volume
17
Issue
21
Year of publication
1998
Pages
6385 - 6393
Database
ISI
SICI code
0261-4189(1998)17:21<6385:DMACIB>2.0.ZU;2-X
Abstract
The relationship between co-suppression and DNA methylation was explor ed in transgenic plants showing inducible co-suppression following inf ection with a cytoplasmically replicating RNA virus. Induction resulte d in a loss of transgene mRNA and resistance to further infection, fac tors typical of post-transcriptional gene silencing. In infected plant s, de novo methylation of the transgene appeared to precede the onset of resistance and only occurred in plants where the outcome was co-sup pression. The methylation was limited to sequences homologous to the v iral RNA and occurred at both symmetric and non-symmetric sites on the DNA. Although methylation is predicted to occur in mitotic cells, the virus was found not to access the meristem. A diffusible sequence-spe cific signal may account for the epigenetic changes in those tissues.