title: Disassembly of synthetic Agrobacterium T-DNA-protein complexes via the host SCF(VBF) ubiquitin-ligase complex pathway.
abstract: One the most intriguing, yet least studied, aspects of the bacterium-host plant interaction is the role of the host ubiquitin/proteasome system (UPS) in the infection process. Increasing evidence indicates that pathogenic bacteria subvert the host UPS to facilitate infection. Although both mammalian and plant bacterial pathogens are known to use the host UPS, the first prokaryotic F-box protein, an essential component of UPS, was identified in Agrobacterium. During its infection, which culminates in genetic modification of the host cell, Agrobacterium transfers its T-DNA--as a complex (T-complex) with the bacterial VirE2 and host VIP1 proteins--into the host cell nucleus. There the T-DNA is uncoated from its protein components before undergoing integration into the host genome. It has been suggested that the host UPS mediates this uncoating process, but there is no evidence indicating that this activity can unmask the T-DNA molecule. Here we provide support for the idea that the plant UPS uncoats synthetic T-complexes via the Skp1/Cullin/F-box protein VBF pathway and exposes the T-DNA molecule to external enzymatic activity.
authors.affiliation: Department of Biochemistry and Cell Biology, State University of New York, Stony Brook, NY 11794, USA.
authors.forename: Adi
authors.initials: A
authors.lastname: Zaltsman
authors.forename: Benoît
authors.initials: B
authors.lastname: Lacroix
authors.forename: Yedidya
authors.initials: Y
authors.lastname: Gafni
authors.forename: Vitaly
authors.initials: V
authors.lastname: Citovsky
mesh_terms: D021581:Active Transport, Cell Nucleus; D060054:Agrobacterium / Q000235:genetics*; D029681:Arabidopsis Proteins / Q000378:metabolism; D001426:Bacterial Proteins / Q000378:metabolism*; D015153:Blotting, Western; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D054884:Host-Pathogen Interactions / Q000502:physiology; D007473:Ion Channels / Q000378:metabolism; D046911:Macromolecular Substances / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014026:Nicotiana; D014170:Transformation, Genetic / Q000502:physiology*
chemical_list: D029681:Arabidopsis Proteins; D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D007473:Ion Channels; D046911:Macromolecular Substances; C036483:T-DNA; C432104:VIP1 protein, Arabidopsis; C051583:virE2 protein, Agrobacterium; D046988:Proteasome Endopeptidase Complex