Found at: doi:10.1371/journal.pone.0006594.s005 (0.41 MB TIF) Figure S6 Lrp5 2/2 MECs are Depleted in Markers Expressed by MRUs. Representative heatmap and stastical analysis micro- array of Lrp5 +/+ and 2/2 RNA samples. Genes previously characterized to be up-regulated in MRUs (Stingl et al, 2006) were compared for each sample using GeneSifter software. Data were compared by student’s t-test, *p,0.05. Found at: doi:10.1371/journal.pone.0006594.s006 (0.96 MB TIF) Figure S7 Cell Culture Does not Alter Lrp5/6 Expression. A) RNA from cultured Lrp5 +/+ and 2/2 MECs was isolated from cells daily, and quantitative RT-PCR was performed for Lrp5 (A) and Lrp6 (B). Expression levels were normalized for each sample using the housekeeping genes, TBP and HPRT. Found at: doi:10.1371/journal.pone.0006594.s007 (0.40 MB TIF) References 1. Klaus A, Birchmeier W (2008) Wnt signalling and its impact on development and cancer. Nat Rev Cancer 8: 387–398. 2. 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