FIGURE 2

Northern blot analysis to depict the expression of MMTV and jun B in various cancerous and normal mouse tissues. Demonstration of the expression of MMTV (Panel A) and jun B (Panel B) in the lactating mammary glands of BALB/fC3H (lane 1) and C57BLfGR (lane 2), and non-lactating mammary gland of BALB/fC3H (lane 3), RIII (lane 4), and WLCO (lane 5) mice. Lane 6 contained an RNA sample from a C57BLfGR tumor as control. RNA was isolated from the tissue, fractionated by an electrophoresis gel, transferred onto a Zeta-probe membrane and hybridized with a MMTVrep probe (Panel A). Subsequently, the filter was stripped off and rehybridized with a jun B probe (Panel B). In each case the filter was exposed to an x-ray film overnight at -70 ° C.