title: RNA-directed de novo methylation of genomic sequences in plants.
abstract: One monomeric and three oligomeric potato spindle tuber viroid (PSTVd) cDNA units were introduced into the tobacco genome via the Agrobacterium-mediated leaf-disc transformation. Southern analysis of the integrates revealed that only their PSTVd-specific sequences become fully methylated, whereas the flanking T-DNA and the genomic plant DNA remain unaltered. Viroid cDNA methylation could only be observed after autonomous viroid RNA-RNA replication had taken place in these plants. These findings demonstrate that a mechanism of de novo methylation of genes might exist that can be induced and targeted in a sequence-specific manner by their own mRNA.
authors.affiliation: Max-Planck-Institut für Biochemie, Abteilung Viroidforschung, Martinsried, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Wassenegger
authors.forename: S
authors.initials: S
authors.lastname: Heimes
authors.forename: L
authors.initials: L
authors.lastname: Riedel
authors.forename: H L
authors.initials: HL
authors.lastname: Sänger
mesh_terms: D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D004247:DNA / Q000378:metabolism*; D004279:DNA, Viral / Q000378:metabolism*; D017343:Genes, Plant; D008745:Methylation; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D012367:RNA, Viral / Q000378:metabolism*; D015183:Restriction Mapping; D012231:Rhizobium / Q000235:genetics / Q000502:physiology*; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism*; D014772:Viroids / Q000502:physiology; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral; D004247:DNA