title: Intrinsic disorder in Viral Proteins Genome-Linked: experimental and predictive analyses.
abstract: BACKGROUND
  VPgs are viral proteins linked to the 5' end of some viral genomes. Interactions between several VPgs and eukaryotic translation initiation factors eIF4Es are critical for plant infection. However, VPgs are not restricted to phytoviruses, being also involved in genome replication and protein translation of several animal viruses. To date, structural data are still limited to small picornaviral VPgs. Recently three phytoviral VPgs were shown to be natively unfolded proteins.
  
  
  RESULTS
  In this paper, we report the bacterial expression, purification and biochemical characterization of two phytoviral VPgs, namely the VPgs of Rice yellow mottle virus (RYMV, genus Sobemovirus) and Lettuce mosaic virus (LMV, genus Potyvirus). Using far-UV circular dichroism and size exclusion chromatography, we show that RYMV and LMV VPgs are predominantly or partly unstructured in solution, respectively. Using several disorder predictors, we show that both proteins are predicted to possess disordered regions. We next extend theses results to 14 VPgs representative of the viral diversity. Disordered regions were predicted in all VPg sequences whatever the genus and the family.
  
  
  CONCLUSIONS
  Based on these results, we propose that intrinsic disorder is a common feature of VPgs. The functional role of intrinsic disorder is discussed in light of the biological roles of VPgs.
authors.affiliation: UMR 1097 Résistance des Plantes aux Bio-agresseurs, IRD, CIRAD, Université de Montpellier II, BP 64501, 34394 Montpellier cedex 5, France. hebrard@mpl.ird.fr
authors.forename: Eugénie
authors.initials: E
authors.lastname: Hébrard
authors.forename: Yannick
authors.initials: Y
authors.lastname: Bessin
authors.forename: Thierry
authors.initials: T
authors.lastname: Michon
authors.forename: Sonia
authors.initials: S
authors.lastname: Longhi
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Uversky
authors.forename: François
authors.initials: F
authors.lastname: Delalande
authors.forename: Alain
authors.initials: A
authors.lastname: Van Dorsselaer
authors.forename: Pedro
authors.initials: P
authors.lastname: Romero
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Walter
authors.forename: Nathalie
authors.initials: N
authors.lastname: Declerck
authors.forename: Denis
authors.initials: D
authors.lastname: Fargette
mesh_terms: D002850:Chromatography, Gel; D002942:Circular Dichroism; D016679:Genome, Viral; D018545:Lactuca / Q000821:virology*; D012275:Oryza / Q000821:virology*; D010935:Plant Diseases / Q000821:virology; D010942:Plant Viruses / Q000737:chemistry / Q000235:genetics / Q000472:pathogenicity; D017800:Potyvirus / Q000737:chemistry / Q000472:pathogenicity; D011237:Predictive Value of Tests; D017510:Protein Folding; D012328:RNA Viruses / Q000737:chemistry / Q000235:genetics / Q000472:pathogenicity; D017361:Viral Nonstructural Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D017361:Viral Nonstructural Proteins