| Based on our evolutionary analyses, we asked whether isolates differed in properties reflecting host-virus interaction in the original chickens host. Our in vitro and in ovo experiments showed that different genetic lineages of GVI-PMV1 exhibited unique phenotypic properties. Using multivariate analysis, we demonstrated that these phenotypic properties measured from cellular and organismal infections were able to discriminate virus lineages. Our data also show that GVIPMV1 displayed unique pattern of altering host type 1 interferon expression and mode of replication in vitro; and the virus pathogenesis is associated with systemic infection and high replication efficiency in chicken embryos. In summary, the studies in this dissertation contribute to a greater understanding of the molecular evolution of PMV1 at global and regional scales, the emergence of one of the new strains, GVI-PMV1 and its global dispersal and establishment in the US, and the possible biological manifestation of the emergent strain to replicate in chickens. (Abstract shortened by UMI.). |
