title: A plastid-targeted heat shock cognate 70kDa protein interacts with the Abutilon mosaic virus movement protein.
abstract: The movement protein (MP) of bipartite geminiviruses facilitates cell-to-cell as well as long-distance transport within plants and influences viral pathogenicity. Yeast two-hybrid assays identified a chaperone, the nuclear-encoded and plastid-targeted heat shock cognate 70kDa protein (cpHSC70-1) of Arabidopsis thaliana, as a potential binding partner for the Abutilon mosaic virus (AbMV) MP. In planta, bimolecular fluorescence complementation (BiFC) analysis showed cpHSC70-1/MP complexes and MP homooligomers at the cell periphery and co-localized with chloroplasts. BiFC revealed cpHSC70-1 oligomers associated with chloroplasts, but also distributed at the cellular margin and in filaments arising from plastids reminiscent of stromules. Silencing the cpHSC70 gene of Nicotiana benthamiana using an AbMV DNA A-derived gene silencing vector induced minute white leaf areas, which indicate an effect on chloroplast stability. Although AbMV DNA accumulated within chlorotic spots, a spatial restriction of these occurred, suggesting a functional relevance of the MP-chaperone interaction for viral transport and symptom induction.
authors.affiliation: Institute of Biology, Department of Molecular Biology and Plant Virology, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Krenz
authors.forename: Volker
authors.initials: V
authors.lastname: Windeisen
authors.forename: Christina
authors.initials: C
authors.lastname: Wege
authors.forename: Holger
authors.initials: H
authors.lastname: Jeske
authors.forename: Tatjana
authors.initials: T
authors.lastname: Kleinow
mesh_terms: D017360:Arabidopsis / Q000378:metabolism / Q000821:virology; D053839:Begomovirus / Q000737:chemistry* / Q000472:pathogenicity; D002736:Chloroplasts / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D053830:Plant Viral Movement Proteins / Q000378:metabolism*; D011485:Protein Binding; D014026:Nicotiana / Q000378:metabolism / Q000821:virology; D020798:Two-Hybrid System Techniques
chemical_list: D018840:HSP70 Heat-Shock Proteins; D010940:Plant Proteins; D053830:Plant Viral Movement Proteins