Fig 5. Lack of Cbl-PI3K interaction results in increased osteoblast surface, incorporation of dynamic bone labels, and up-regulation of master transcription factor Osterix in remodeling fracture calluses.

Mid-saggital sections of fractured femora were stained with Safranin O and Fast Green, and counterstained with Hematoxylin. A. Representative sections at 7, 14, 21, and 28 days post-fracture showing bony regions of fracture calluses. B. Osteoblast surface over bone surface (ObS/BS) measured by static histomorphometry. n = 6, *p<0.05 vs. WT. C. Mice were injected with Alizarin Complexone (red) 4 days prior to sacrifice, and Calcein (green) 1 day prior to sacrifice. Mid-sagittal sections of fractured femora were used to image incorporation of dynamic bone labels in the center of the fracture calluses at 14 and 21 days post-fracture. Cells from sections of calluses at 7, 14, and 21 days post-fracture were harvested by LCM, and expression of D. Runx2, and E. Osterix were quantified by qRT-PCR n = 6, *p<0.05 vs. WT.