title: The glutathione transferase of Nicotiana benthamiana NbGSTU4 plays a role in regulating the early replication of Bamboo mosaic virus.
abstract: Bamboo mosaic virus (BaMV) is a single-stranded positive-sense RNA virus. One of the plant glutathione S-transferase (GST) genes, NbGSTU4, responds as an upregulated gene in Nicotiana benthamiana post BaMV infection. In order to identify the role of NbGSTU4 in BaMV infection, the expression of NbGSTU4 was knocked down using a virus-induced gene silencing technique or was transiently expressed in N. benthamiana in BaMV inoculation. The results show a significant decrease in BaMV RNA accumulation when the expression level of NbGSTU4 is reduced; whereas the viral RNA accumulation increases when NbGSTU4 is transiently expressed. Furthermore, this study identified that the involvement of NbGSTU4 in viral RNA accumulation occurs by its participation in the viral early replication step. The findings show that the NbGSTU4 protein expressed from Escherichia coli can interact with the 3' untranslated region (UTR) of the BaMV RNA in vitro in the presence of glutathione (GSH). The addition of GSH in the in vitro replication assay shows an enhancement of minus-strand but not plus-strand RNA synthesis. The results suggest that the plant GST protein plays a role in binding viral RNA and delivering GSH to the replication complex to create a reduced condition for BaMV minus-strand RNA synthesis.
authors.affiliation: Graduate Institute of Biotechnology, National Chung Hsing University, Taichung, Taiwan.
authors.forename: I-Hsuan
authors.initials: IH
authors.lastname: Chen
authors.forename: Meng-Hsuen
authors.initials: MH
authors.lastname: Chiu
authors.forename: Shun-Fang
authors.initials: SF
authors.lastname: Cheng
authors.forename: Yau-Heiu
authors.initials: YH
authors.lastname: Hsu
authors.forename: Ching-Hsiu
authors.initials: CH
authors.lastname: Tsai
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics; D015153:Blotting, Western; D003432:Cross-Linking Reagents / Q000494:pharmacology; D055785:Gene Knockdown Techniques; D005978:Glutathione / Q000494:pharmacology; D005982:Glutathione Transferase / Q000378:metabolism*; D009029:Mosaic Viruses / Q000187:drug effects / Q000502:physiology* / Q000528:radiation effects; D010084:Oxidation-Reduction / Q000187:drug effects / Q000528:radiation effects; D010940:Plant Proteins / Q000378:metabolism*; D012367:RNA, Viral / Q000096:biosynthesis / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D014026:Nicotiana / Q000187:drug effects / Q000201:enzymology* / Q000528:radiation effects / Q000821:virology*; D014466:Ultraviolet Rays; D014779:Virus Replication / Q000187:drug effects / Q000528:radiation effects
chemical_list: D020413:3' Untranslated Regions; D003432:Cross-Linking Reagents; D010940:Plant Proteins; D012367:RNA, Viral; D005982:Glutathione Transferase; D012324:RNA-Dependent RNA Polymerase; D005978:Glutathione
keywords: Bamboo mosaic virus (BaMV); glutathione (GSH); glutathione S-transferase (GST); in vitro RNA replication; redox; viral RNA replication; virus-induced gene silencing (VIGS)