ANALYSIS OF THE INFECTIVITY OF MONOMERIC CLONES OF PEPPER HUASTECO VIRUS

The infectivity of several monomeric clones of pepper huasteco virus w as investigated. All clones were infectious when inoculated excised fr om the plasmid DNA. However, only certain clones were infectious when inoculated in the non-excised form. Constructs in which the cloning si te lies inside regions or genes involved in replication (e.g. Rep-bind ing site, rep and AC2-AC3 genes) were not infectious whereas construct s in which the site was located inside the CP or BC1 genes were infect ious. A clone that interrupts the BV1 gene was not infectious suggesti ng an early role of BV1 during the establishment of the infection. Lin ear viral clones containing different DNA fragments at both extremes w ere also infectious although with a lower efficiency. Analysis of the progeny suggested a precise excision mechanism since in most cases onl y wild type virus was recovered. The results suggest that excision cou ld be linked to replication through a very specific recombination proc ess.