Virulent Marek's disease virus generated from infectious bacterial artificial chromosome clones with complete DNA sequence and the implication of viral genetic homogeneity in pathogenesis

• DOI: 10.1099/vir.0.026864-0
• Publication Date: 2010-12-02T05:50:43Z
• Authors: M. Niikura; T. Kim; R. F. Silva; J. Dodgson; H. H. Cheng
• Keywords: Bacterial artificial chromosome; ORFS

Genetic homogeneity of a test population is essential to precisely associate viral genome sequence and its phenotype at the nucleotide level. However, not easy achieve for Marek's disease virus (MDV) due strictly cell-associated replication. To address this problem, two virulent infectious bacterial artificial chromosome (BAC) clones MDV were generated from an previously cloned as five overlapping cosmids. The Md5SN5BAC clone has BAC vector inserted between 3′ ends UL3 UL4, such that no known ORFs should be disrupted. flanked by loxP sites, so it can deleted transfecting into newly developed chicken cell line constitutively expresses Cre recombinase. Md5B40BAC replacing portion US2, location similar used other groups construct MDV-BAC clones. Although both BACs capable producing when inoculated susceptible chickens, Md5B40BAC-derived viruses showed somewhat better replication in vivo higher virulence. Removal Md5SN5BAC-derived had influence on Interestingly, genetically homogeneous was mixed with avirulent virus, overall virulence noticeably compromised, which emphasizes importance complexity pathogenesis.