title: Limitations on the use of fused green fluorescent protein to investigate structure-function relationships for the cauliflower mosaic virus movement protein.
abstract: To investigate the process of tubule formation for the cauliflower mosaic virus movement protein (CaMV MP), the green fluorescent protein (GFP) was fused to the MP to provide a vital marker for MP location after expression in insect cells. In contrast to the long tubular structures seen previously following baculovirus-based expression of the wild-type MP, the fusion protein produced only aggregates of fluorescing material in the cytoplasm. However, by co-expressing wild-type MP and GFP-MP, or by engineering their co-accumulation by introducing a foot-and-mouth disease virus 2A cleavage sequence between GFP and MP, long GFP-fluorescing tubules were formed. The experiments suggest that the presence of GFP at the N or C terminus of the tubule-forming domain of the CaMV MP places steric constraints upon the aggregation of the MP into a tubule but that this can be overcome by providing wild-type protein for inclusion in the aggregate.
authors.affiliation: John Innes Centre, Norwich Research Park, Colney, Norwich NR4 7UH, UK.
authors.forename: C L
authors.initials: CL
authors.lastname: Thomas
authors.forename: A J
authors.initials: AJ
authors.lastname: Maule
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001937:Brassica / Q000821:virology*; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009029:Mosaic Viruses / Q000737:chemistry*; D053830:Plant Viral Movement Proteins; D018411:Spodoptera; D013329:Structure-Activity Relationship; D014764:Viral Proteins / Q000737:chemistry / Q000502:physiology*
chemical_list: D008164:Luminescent Proteins; D053830:Plant Viral Movement Proteins; D014764:Viral Proteins; D049452:Green Fluorescent Proteins