Figure 2

Expression of lineage markers in mammary glands of MMTVrtTA/H2BGFP mice. Mammary glands were harvested from four-week-old double transgenic females treated with doxycycline, sectioned and immunostained for: (a) β1 integrin (b) CK8 (c) CK14 or (d) p63. Each pair of micrographs depicts ducts (upper) and terminal end buds (lower), at 60× magnification. Note that, as expected, cytoplasmic (CK8, CK14) and cell surface (β1 integrin) lineage markers do not co-localize with H2BGFP in cells that co-express both proteins; only with p63, which is a nuclear protein, does co-expression result in co-localization with H2BGFP. In all panels, representative co-expressing cells are indicated by arrowheads. H2BGFP, histone 2B-eGFP; MMTV, mouse mammary tumor virus promoter; rtTA, reverse tetracycline transactivator.