TUBULE-FORMING CAPACITY OF THE MOVEMENT PROTEINS OF ALFALFA MOSAIC-VIRUS AND BROME MOSAIC-VIRUS

The structural phenotype of the movement proteins (MPs) of two represe ntatives of the Bromoviridae, alfalfa mosaic virus (AMV) and brome mos aic virus (BMV), was studied in protoplasts. Immunofluorescence micros copy showed that the MPs of these viruses, for which there has been no evidence of a tubule-guided mechanism, assemble into long tubular str uctures at the surface of the infected protoplast. Electron microscopy and immunogold analysis confirmed the presence of both MP and virus p articles in the tubules induced by AMV and BMV. The significance of th e tubule-forming properties of these viral MPs is discussed.