Posttranscriptional gene silencing of gn1 in tobacco triggers accumulation of truncated gn1-derived RNA species

• Published in: RNA (Cambridge) 1999-10, Vol.5 (10), p.1364-1373, Article S1355838299990799
• Main Authors: LITIÈRE, KATIA, VAN ELDIK, GERBEN J., JACOBS, JOHN J.M.R., VAN MONTAGU, MARC, CORNELISSEN, MARC
• Format: Article
• Language: English
• Subjects: 1,3-^b-glucanase; Base Sequence; beta-Glucosidase - genetics; DNA, Plant; Gene Silencing; Genes, Plant; Glucan 1,3-beta-Glucosidase; gn1 gene; Molecular Sequence Data; Nicotiana; Nicotiana - enzymology; Nicotiana - genetics; Plants, Genetically Modified; Plants, Toxic; Protein Biosynthesis; RNA, Plant
• ISSN: 1355-8382; 1469-9001
• DOI: 10.1017/S1355838299990799

Posttranscriptional silencing of basic β-1,3-glucanase genes in the tobacco line T17 is manifested by reduced transcript levels of the gn1 transgene and homologous, endogenous basic β-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 β-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.