Expression of transgenic Wif1 in bone. (A) Bones were crushed from cohorts of Wif1 and OB mice and collagenased. Resultant cells were lineage depleted and profiled for GFP expression by flow cytometry. Gating is on viable lineage-negative cells. There are similar numbers of GFP⁺ cells in the bones of Wif1 (0.0088% ± 0.00013%; n = 8) and OB (0.011% ± 0.00014%; n = 15) mice. (B) Expression of Wif1 (both endogenous and transgenic) in sorted GFP⁺ cells from Wif1 mice was compared with that in GFP⁺ cells from OB mice (expression arbitrarily set to 1). Five animals were pooled for sorting. Data are represented as relative Wif1 mRNA expression levels ± SD (n = 2).