title: RNA-dependent RNA polymerase 6 is required for efficient hpRNA-induced gene silencing in plants.
abstract: In plants, transgenes with inverted repeats are used to induce efficient RNA silencing, which is also frequently induced by highly transcribed sense transgenes. RNA silencing induced by sense transgenes is dependent on RNA-dependent RNA polymerase 6 (RDR6), which converts single-stranded (ss) RNA into double-stranded (ds) RNA. By contrast, it has been proposed that RNA silencing induced by self-complementary hairpin RNA (hpRNA) does not require RDR6, because the hpRNA can directly fold back on itself to form dsRNA. However, it is unclear whether RDR6 plays a role in hpRNA-induced RNA silencing by amplifying dsRNA to spread RNA silencing within the plant. To address the efficiency of hpRNA-induced RNA silencing in the presence or absence of RDR6, Wild type (WT, Col-0) and rdr6-11 Arabidopsis thaliana lines expressing green fluorescent protein (GFP) were generated and transformed with a GFP-RNA interference (RNAi) construct. Whereas most GFP-RNAi-transformed WT lines exhibited almost complete silencing of GFP expression in the T1 generation, various levels of GFP expression remained among the GFP-RNAi-transformed rdr6-11 lines. Homozygous expression of GFP-RNAi in the T3 generation was not sufficient to induce complete GFP silencing in several rdr6-11 lines. Our results indicate that RDR6 is required for efficient hpRNA-induced RNA silencing in plants.
authors: Division of Applied Life Science (Brain Korea 21 Program) and Plant Molecular Biology Biotechnology Research Center (PMBBRC), Gyeongsang National University, Jinju 660-701, Korea.
authors: Rikno
authors: R
authors: Harmoko
authors: Wahyu Indra Duwi
authors: WI
authors: Fanata
authors: Jae Yong
authors: JY
authors: Yoo
authors: Ki Seong
authors: KS
authors: Ko
authors: Yeong Gil
authors: YG
authors: Rim
authors: Mohammad Nazim
authors: MN
authors: Uddin
authors: Tri Agus
authors: TA
authors: Siswoyo
authors: Seung Sik
authors: SS
authors: Lee
authors: Dool Yi
authors: DY
authors: Kim
authors: Sang Yeol
authors: SY
authors: Lee
authors: Kyun Oh
authors: KO
authors: Lee
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000502:physiology*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D055029:Inverted Repeat Sequences; D009154:Mutation; D010641:Phenotype; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics*; D012324:RNA-Dependent RNA Polymerase / Q000502:physiology*; D036226:Seedlings / Q000201:enzymology* / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D034741:RNA, Small Interfering; D049452:Green Fluorescent Proteins; C514575:RDR6 protein, Arabidopsis; D012324:RNA-Dependent RNA Polymerase