Exogenous mouse mammary tumor virus (MMTV) was cloned from a GR mammary tumor. Clone λGRT39 contained a full-length integrated MMTV(GR) provirus and both 5' and 3' host flanking DNA. The λGRT39 provirus had no apparent structural changes associated with cloning and retained the exogenous MMTV gag gene poison sequence. When introduced into rat mammary adenocarcinoma LA7 cells, the λGRT39 provirus was fully expressed. λGRT39-transfected LA7 cells made MMTV RNA, had gp52 SU protein on the cell surface, and produced B-type retrovirus particles characteristic of MMTV. Mammary tumors developed in hormone-stimulated BALB/c females injected with MMTV from λGRT39-transfected LA7 cells [MMTV(λGRT39)]. The tumors had new, clonally integrated copies of the MMTV(λGRT39) provirus and were expressing MMTV antigen. These data indicate that the λGRT39 provirus is biologically active and pathogenic.
|Original language||English (US)|
|Number of pages||11|
|Journal||Journal of Virology|
|State||Published - Jan 1 1989|
ASJC Scopus subject areas
- Insect Science