Cooperative binding of the red clover necrotic mosaic virus movement protein to single-stranded nucleic acids.

The movement protein of red clover necrotic mosaic dianthovirus was produced in Escherichia coli using an expression vector. Gel retardation analysis and u.v. cross-linking studies showed that the movement protein bound cooperatively to ssRNA and ssDNA, but not to dsDNA. Binding competition experiments established that the movement protein bound to ssRNA and ssDNA with similar affinities and that the binding was not sequence-specific in the experimental conditions employed. A truncated movement protein lacking the C-terminal 88 amino acids was also shown to bind to ssRNA.