The movement proteins of two tobamoviruses (tobacco mosaic virus, TMV, common strain U1 and cruciferous TMV strain) containing amino-terminal hexahistidine affinity tags were overexpressed in Escherichia coli and purified by metal chelate affinity chromatography. Purified recombinant proteins were immobilized to a Ni 2 + -chelate adsorbent and their ability to interact with full-length genomic TMV RNA was tested. Here we report that binding of viral RNA to hexahistidine fusion movement proteins results in the formation of stable ribonucleoprotein complexes.