SHIP is expressed and phosphorylated in BM niche cells. (A) Representative SHIP Western blot from stromal cells cultured from the BM of SHIP^−/− and WT littermates. (B) SHIP Western blot from osteoblast cells cultured from the BM of SHIP^−/− and WT littermates. (C) pTyr Western blot on a SHIP immunoprecipitation of stromal cells cultured from the BM of SHIP^−/− and WT littermates. (D) SHIP Western blot from stromal cells cultured from the BM of MxCreSHIP^flox/flox and SHIP^flox/flox littermates. Each lane on the Western blots represents a culture lysate derived from an independent mouse.