title: Multiple domains within the Cauliflower mosaic virus gene VI product interact with the full-length protein.
abstract: The Cauliflower mosaic virus (CaMV) gene VI product (P6) is a multifunctional protein essential for viral propagation. It is likely that at least some of these functions require P6 self-association. The work described here was performed to confirm that P6 self-associates and to identify domains involved in this interaction. Yeast two-hybrid analyses indicated that full-length P6 self-associates and that this interaction is specific. Additional analyses indicated that at least four independent domains bind to full-length P6. When a central domain (termed domain D3) was removed, these interactions were abolished. However, this deleted P6 was able to bind to the full-length wild-type protein and to isolated domain D3. Viruses lacking domain D3 were incapable of producing a systemic infection. Isolated domain D3 was capable of binding to at least two of the other domains but was unable to self-associate. This suggests that domain D3 facilitates P6 self-association by binding to the other domains but not itself. The presence of multiple domains involved in P6 self-association may help explain the ability of this protein to form the intracellular inclusions characteristic of caulimoviruses.
authors.affiliation: Department of Biological Sciences, The University of Toledo, OH 43606, USA.
authors.forename: Yongzhong
authors.initials: Y
authors.lastname: Li
authors.forename: Scott M
authors.initials: SM
authors.lastname: Leisner
mesh_terms: D001665:Binding Sites / Q000235:genetics; D001937:Brassica / Q000821:virology; D017796:Caulimovirus / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D009154:Mutation; D010942:Plant Viruses / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D011485:Protein Binding; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism; D015003:Yeasts / Q000235:genetics
chemical_list: D015534:Trans-Activators; D014764:Viral Proteins; C095687:gene VI protein, Cauliflower mosaic virus