Induction of B-tropic and N-tropic murine leukemia virus from B10.BR/SgLi mouse embryo cell lines by 5-iodo-2'-deoxyuridine.

In contrast to the original B10.BR/SgSn congenic mouse strain, adult mice of the B10.BR/SgLi subline showed a high level of expression of B-tropic ecotropic murine leukemia virus (MuLV). Both B-tropic and N-tropic ecotropic MuLV could be included in cultures of virus-free cell lines derived from embryos of B10.BR/SgLi mice. Both various were also inducible from each of several clonal cell lines and from cultures of F1 embryos of matings of B10.BR/SgLi males with females of strains NFS/N and A/J, which are negative for B-tropic virus. Thus the information for B-tropic MuLV as well as that for N-tropic MuLV was transmitted as a genetic element in the B10.BR/SgLi subline.