The transgene comprises the 218.50-kb mouse genomic DNA insert of the bacterial artificial chromosome (BAC) clone RP23-215F15 (RPCI library; C57BL/6J), which contains the entire phosphatase and tensin homolog (Pten) gene. Immunoblot analysis of whole-cell protein extracts from mouse embryonic fibroblasts (MEFs) cultured from E13.5 embryos of this line shows that they express the protein at 3.5-fold the level of wild-type MEFs; elevated levels are observed in both cytoplasmic and nuclear MEF extracts. Elevated PTEN protein expression is observed in embryos and in all adult tissues analyzed: brain, lung, kidney, heart, thymus, liver, spleen, and white and brown adipose tissue. (J:186096)