THE MINIMAL 5' SEQUENCE FOR IN-VITRO INITIATION OF PAPAYA MOSAIC POTEXVIRUS ASSEMBLY

The minimal 5′ initiation of assembly sequence for papaya mosaic virus (PMV) has been determined by the generation of successive 3′ deletion clones from a full-length cDNA copy of the PMV genome followed by in vitro assembly of RNA transcripts. Sequences closest to the 5′ terminus were cloned into plasmid vectors with synthetic complementary oligonucleotides representing viral sequences. The in vitro initiation sequence has been narrowed down to 38-47 nucleotides at the 5′ terminus which are capable of initiation alone or in conjunction with homologous or heterologous sequences. The minimum initiation sequence is rich in adenosine and cytidine and very poor in uridine nucleotides and lacks any discernible secondary structure. © 1994 Academic Press. All rights reserved.