title: Interaction of the host protein NbDnaJ with Potato virus X minus-strand stem-loop 1 RNA and capsid protein affects viral replication and movement.
abstract: Plant viruses must interact with host cellular components to replicate and move from cell to cell. In the case of Potato virus X (PVX), it carries stem-loop 1 (SL1) RNA essential for viral replication and movement. Using two-dimensional electrophoresis northwestern blot analysis, we previously identified several host proteins that bind to SL1 RNA. Of those, we further characterized a DnaJ-like protein from Nicotiana benthamiana named NbDnaJ. An electrophoretic mobility shift assay confirmed that NbDnaJ binds only to SL1 minus-strand RNA, and bimolecular fluorescence complementation (BiFC) indicated that NbDnaJ interacts with PVX capsid protein (CP). Using a series of deletion mutants, the C-terminal region of NbDnaJ was found to be essential for the interaction with PVX CP. The expression of NbDnaJ significantly changed upon infection with different plant viruses such as PVX, Tobacco mosaic virus, and Cucumber mosaic virus, but varied depending on the viral species. In transient experiments, both PVX replication and movement were inhibited in plants that over-expressed NbDnaJ but accelerated in plants in which NbDnaJ was silenced. In summary, we suggest that the newly identified NbDnaJ plays a role in PVX replication and movement by interacting with SL1(-) RNA and PVX CP.
authors.affiliation: Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea.
authors.forename: Sang-Yun
authors.initials: SY
authors.lastname: Cho
authors.forename: Won Kyong
authors.initials: WK
authors.lastname: Cho
authors.forename: Seong-Han
authors.initials: SH
authors.lastname: Sohn
authors.forename: Kook-Hyung
authors.initials: KH
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D036022:Capsid Proteins / Q000378:metabolism*; D024202:Electrophoretic Mobility Shift Assay; D050956:HSP40 Heat-Shock Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D054884:Host-Pathogen Interactions; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010802:Phylogeny; D010940:Plant Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D017863:Potexvirus / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D012367:RNA, Viral / Q000737:chemistry / Q000378:metabolism*; D014026:Nicotiana / Q000378:metabolism* / Q000821:virology*; D014779:Virus Replication
chemical_list: D036022:Capsid Proteins; D050956:HSP40 Heat-Shock Proteins; D010940:Plant Proteins; D012367:RNA, Viral