A short basic domain supports a nucleic acid-binding activity in the rice tungro bacilliform virus open reading frame 2 product.
Little is known about the features of badnavirus open reading frame 2 products (P2). So far, no consensus functional domain has been found in these proteins. However, they all have in common at their C-terminus amino acids which may have the capacity to bind nucleic acids. Such capacity has already been established for cacao swollen shoot virus protein P2. We have looked for such a binding capacity of rice tungro bacilliform virus (RTBV) ORF 2 product. For this purpose, the protein was expressed as full-length or truncated versions in Escherichia coli. When used in nucleic acid-binding assays, complete RTBV P2 was shown to bind both DNA and RNA. This property may be related to a basic sequence, PPKKGIKRKYPA, localized at its C-terminus. Mutations were introduced into this sequence and revealed that four of the five basic residues, including a crucial lysine, are required for the binding to nucleic acids. Moreover, this sequence can confer binding capacity when it is fused to the N-terminus of nonbinding proteins.
Jacquot
E
E
Institut de Biologie Moléculaire des Plantes du Centre National de la Recherche Scientifique, Université Louis Pasteur, Strasbourg, France.
Keller
M
M
Yot
P
P
D000595:Amino Acid Sequence; D019195:Badnavirus / Q000235:genetics*; D004279:DNA, Viral / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D008239:Lysine / Q000737:chemistry; D016366:Open Reading Frames; D012275:Oryza / Q000821:virology*; D017434:Protein Structure, Tertiary; D012367:RNA, Viral / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D014764:Viral Proteins / Q000737:chemistry / Q000378:metabolism*
D004279:DNA, Viral; D004268:DNA-Binding Proteins; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; D008239:Lysine