Abstract
The precipitate of 105, 000g centrifugation (P3 fraction) obtained from the homogenate of tobacco leaves inoculated with 32P-labeled TMV was analyzed by the sucrose density gradient centrifugation. In addition to TMV peak, one or two shoulders appeared in the density gradient patterns and these shoulders became distinct and formed a peak with the progress of infection, particularly 6 hours after inoculation. RNase treatment of the homogenate and the density gradient patterns shown by the inoculation with 35S-labeled TMV revealed the protein nature of these peaks and shoulders. Control experiments confirmed the validity of this density gradient profile. Dissociation of one part, at least, of TMV coat protein immediately after the infection of tobacco leaves is discussed.
