In vitro Encapsidation of Cucumber Mosaic Virus RNA Species.

RNAs and coat protein of cucumber mosaic virus (CMV) strain Y were dissociated with LiCl, and in vitro homologous reassembly was examined. The reassembly products obtained by various protein-RNA ratios were analyzed by analytical sedimentation and gel electrophoresis. When the reassembly was carried out with a deficit of protein against the RNA, both encapsidated and unencapsidated RNA were detected, and encapsidated RNAs consisted mainly RNAs 1, 2 and partly 3, but only little encapsidated RNA 4 and satellite RNA. With sufficient protein, not only RNAs 1-3 but also RNA 4 and satellite RNA were fully encapsidated. It seems that encapsidation efficiency is different for the various virus RNA species, the high molecular weight RNAs 1 and 2 being preferentially encapsidated. Besides, it was confirmed that each of CMV RNAs or the satellite RNA was able to be encapsidated independently and formed virions.