title: Delayed-onset enzootic bovine leukosis possibly caused by superinfection with bovine leukemia virus mutated in the pol gene.
abstract: Bovine leukemia virus (BLV) is the causative agent of enzootic bovine leucosis (EBL), to which animals are most susceptible at 4-8 years of age. In this study, we examined tumor cells associated with EBL in an 18-year-old cow to reveal that the cells carried at least two different copies of the virus, one of which was predicted to encode a reverse transcriptase (RT) lacking ribonuclease H activity and no integrase. Such a deficient enzyme may exhibit a dominant negative effect on the wild-type RT and cause insufficient viral replication, resulting in delayed tumor development in this cow.
authors.affiliation: Laboratory of Microbiology and Immunology, Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido, Ishikari-Tobetsu, Hokkaido, 061-0293, Japan.
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Watanabe
authors.forename: Emi
authors.initials: E
authors.lastname: Inoue
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Mori
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Osawa
authors.forename: Katsunori
authors.initials: K
authors.lastname: Okazaki
mesh_terms: D000818:Animals; D002417:Cattle; D016583:Enzootic Bovine Leukosis / Q000821:virology*; D015684:Gene Products, pol / Q000235:genetics* / Q000378:metabolism; D001909:Leukemia Virus, Bovine / Q000201:enzymology* / Q000235:genetics / Q000502:physiology; D009154:Mutation; D015163:Superinfection; D014779:Virus Replication
chemical_list: D015684:Gene Products, pol