title: Posttranscriptional gene silencing of gn1 in tobacco triggers accumulation of truncated gn1-derived RNA species.
abstract: Posttranscriptional silencing of basic beta-1,3-glucanase genes in the tobacco line T17 is manifested by reduced transcript levels of the gn1 transgene and homologous, endogenous basic beta-1,3-glucanase genes. An RNA ligation-mediated rapid amplification of cDNA ends (RLM-RACE) technique was used to compare the 3' termini of gn1 RNAs present in expressing (hemizygous and young homozygous) and silenced (mature homozygous) T17 plants. Full-length, polyadenylated gn1 transcripts primarily accumulated in expressing plants, whereas in silenced T17 plants, mainly 3'-truncated, nonpolyadenylated gn1 RNAs were detected. The relative abundance of these 3'-truncated gn1 RNA species gradually increased during the establishment of silencing in homozygous T17 plants. Similar 3'-truncated, nonpolyadenylated gn1 RNA products were observed in an independent case of beta-1,3-glucanase posttranscriptional gene silencing. This suggests that these 3'-truncated gn1 RNAs are a general feature of tobacco plants showing posttranscriptional silencing of the gn1 transgene.
authors.affiliation: Departement Genetica, Vlaams Interuniversitair Instituut voor Biotechnologie, Universiteit Gent, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Litière
authors.forename: G J
authors.initials: GJ
authors.lastname: van Eldik
authors.forename: J J
authors.initials: JJ
authors.lastname: Jacobs
authors.forename: M
authors.initials: M
authors.lastname: Van Montagu
authors.forename: M
authors.initials: M
authors.lastname: Cornelissen
mesh_terms: D001483:Base Sequence; D018744:DNA, Plant; D020868:Gene Silencing; D017343:Genes, Plant; D043326:Glucan 1,3-beta-Glucosidase; D008969:Molecular Sequence Data; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D014176:Protein Biosynthesis; D018749:RNA, Plant; D014026:Nicotiana / Q000201:enzymology* / Q000235:genetics; D001617:beta-Glucosidase / Q000235:genetics*
chemical_list: D018744:DNA, Plant; D018749:RNA, Plant; D001617:beta-Glucosidase; D043326:Glucan 1,3-beta-Glucosidase