title: Simian virus 40 integration site in an adenovirus 7-simian virus 40 hybrid DNA molecule.
abstract: The E46(+) strain of Adenovirus 7 is a mixed-virus population containing defective Adenoviurs 7-SV40 hybrid particles and helper, nonhybrid Adenovirus 7 particles. We have applied electron microscopic mapping techniques to obtain a physical map of the genome of the hybrid particles present in E46(+)PL1, a substrain of E46(+) derived from a single two-hit plaque. DNA molecules extracted from purified E46(+)Pl1 virions were found to be linear duplexes, with a mean lenght of 10.9 mum. When these molecules were denatured and renatured, a unique heteroduplex was formed that presumably derived one of its strands from an Adenovirus 7-SV40 hybrid molecule and the other from a nonhybrid Adenovirus 7 molecule. This heteroduplex was double-stranded, except for a short region near one end where the two strands were not paired. On the basis of measurements of the lengths of the single-and double-stranded regions in the heteroduplex, the structure of the Adenovirus 7-SV40 hybrid genome can be reconstructed as follows: The hybrid genome contains 16% less Adenovirus 7 DNA than the nonhybrid Adenovirus 7 genome. This deletion consists of the segment of DNA that maps between 0.05 and 0.21 molecular lenghts in the nonhybrid Adenovirus 7 DNA molecule. The deleted DNA has been partially replaced by an amount of heterologous DNA equivalent to 75% of the complete SV40 genome. A model for the generation of the hybrid genome is presented.
mesh_terms: D000256:Adenoviridae / Q000032:analysis*; D000818:Animals; D004279:DNA, Viral / Q000032:analysis*; D003673:Defective Viruses / Q000032:analysis; D005827:Genetics, Microbial; D000882:Haplorhini; D006824:Hybridization, Genetic; D008854:Microscopy, Electron; D008961:Models, Structural; D009691:Nucleic Acid Denaturation; D009693:Nucleic Acid Hybridization; D013539:Simian virus 40 / Q000032:analysis*
chemical_list: D004279:DNA, Viral