title: RNA silencing is induced by the expression of foreign recombinant products in transgenic rice.
abstract: RNA silencing plays important roles in the regulation of gene expression in eukaryotes. We previously reported that RNA silencing of a linked endogenous gene and a transgene in transgenic rice seeds can be induced by the expression of foreign recombinant mGLP-1, which acts as a silencing-inducible sequence through RNA interference. In this study, we found that the induction of RNA silencing by foreign transgenes is not restricted to mGLP-1 but is observed in many other genes as a relatively general phenomenon, as several foreign genes were involved in inducing RNA silencing in the same manner as mGLP-1 in transgenic rice. We detected 21-24-nt siRNAs using both sense and antisense probes specific to the silenced genes in both the leaves and endosperm of transgenic rice plants. Moreover, read-through transcripts were consistently observed in silenced transgenic rice plants. Taken together, these results suggest that proper transcription termination was prevented in these plants, and the highly divergent 3'-end transcripts served as templates for double-stranded RNA synthesis, resulting in the degradation of the target genes via siRNA.
authors.affiliation: Functional Transgenic Crops Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Lijun
authors.initials: L
authors.lastname: Yang
authors.affiliation: Functional Transgenic Crops Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Taiji
authors.initials: T
authors.lastname: Kawakatsu
authors.affiliation: Functional Transgenic Crops Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Yuhya
authors.initials: Y
authors.lastname: Wakasa
authors.affiliation: Functional Transgenic Crops Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki 305-8602, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Yoine
authors.affiliation: Functional Transgenic Crops Research Unit, Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Kannondai 2-1-2, Tsukuba, Ibaraki 305-8602, Japan. Electronic address: takaiwa@affrc.go.jp.
authors.forename: Fumio
authors.initials: F
authors.lastname: Takaiwa
mesh_terms: D056625:Endosperm; D018506:Gene Expression Regulation, Plant; D020868:Gene Silencing; D017343:Genes, Plant; D052216:Glucagon-Like Peptide 1 / Q000235:genetics; D012275:Oryza / Q000235:genetics* / Q000378:metabolism; D018515:Plant Leaves; D010940:Plant Proteins / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D016372:RNA, Antisense; D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D034741:RNA, Small Interfering / Q000378:metabolism*; D011994:Recombinant Proteins / Q000235:genetics* / Q000378:metabolism; D012639:Seeds; D014158:Transcription, Genetic; D019076:Transgenes
chemical_list: D010940:Plant Proteins; D016372:RNA, Antisense; D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011994:Recombinant Proteins; D052216:Glucagon-Like Peptide 1
keywords: Co-suppression; Oryza sativa L.; RNA silencing; Transcript read-through; Transgene; siRNA