Mapping of viral RNA sequences required for assembly of peanut clump virus particles.

RNA sequences required for assembly into rod-shaped virions of RNA-1 and RNA-2 of Peanut clump virus (PCV) were mapped by testing the ability of different RNA-1 and -2 deletion mutants to be encapsidated in vivo in an RNase-resistant form. Encapsidation of RNA-1 was found to require a sequence domain in the 5'-proximal part of the P15 gene, the 3'-proximal gene of RNA-1. On the other hand, the subgenomic RNA which encodes P15 was not encapsidated, suggesting that other features of RNA-1 are important as well. Two sequences which could drive encapsidation of RNA-2 deletion mutants were located. One was in the 5'-proximal coat protein gene and the other in the P14 gene near the RNA 3' terminus. There were no obvious sequence homologies between the different assembly initiation sequences.