Nucleic acid-binding properties and subcellular localization of the 3a protein of brome mosaic bromovirus.
Brome mosaic bromovirus (BMV) 3a protein is required for cell-to-cell movement of the virus in host plants. The BMV 3a protein (B3a) was produced in Escherichia coli using an expression vector. Gel retardation analysis and UV cross-linking experiments demonstrated that B3a bound single-stranded RNA cooperatively without sequence specificity. Binding competition analysis showed that B3a bound to single-stranded nucleic acids more strongly than to double-stranded nucleic acids. Deletion mutagenesis located a nucleic acid-binding domain to amino acids 189-242. Western blot analysis of fractionated proteins of BMV-infected barley using monoclonal antibodies against B3a indicated that B3a may interact with membrane materials and form complexes in the cytoplasm. Immunogold labelling of thin sections of infected barley tissues revealed that B3a was associated with plasmodesmata and cytoplasmic inclusions.
Fujita
M
M
Laboratory of Plant Pathology, Graduate School of Agriculture, Kyoto University, Japan. miki@kais.kyoto-u.ac.jp
Mise
K
K
Kajiura
Y
Y
Dohi
K
K
Furusawa
I
I
D000595:Amino Acid Sequence; D001665:Binding Sites; D017795:Bromovirus / Q000378:metabolism*; D015870:Gene Expression; D001467:Hordeum / Q000378:metabolism; D007181:Inclusion Bodies, Viral; D008969:Molecular Sequence Data; D053830:Plant Viral Movement Proteins; D012313:RNA / Q000378:metabolism*; D012330:RNA, Double-Stranded / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D017384:Sequence Deletion; D013347:Subcellular Fractions; D014764:Viral Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
D053830:Plant Viral Movement Proteins; D012330:RNA, Double-Stranded; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; D012313:RNA