Fig. 6.
OCPs require primary cilia to respond to paracrine signals from mechanically stimulated osteocytes. Primary periosteal OCPs isolated from 3-week-old Prx1CreER-GFP;Ift88fl/fl mice were treated with the active compound of tamoxifen to disrupt ciliogenesis or vehicle control and then treated with conditioned media from MLO-Y4s exposed to oscillatory fluid flow (OFF) or static controls. Vehicle control OCPs (white) demonstrated a nearly twofold increase in Osteopontin (OPN) (a), Runt-related transcription factor 2 (RUNX2) (b), and Bone gamma-carboxyglutamic acid-containing protein (BGLAP) expression (c). This effect was lost in OCPs treated with tamoxifen (gray). mRNA expression was normalized to GAPDH expression and OFF samples were normalized to static controls. Data are reported as mean and standard error. n = 5 for both groups, ***p < 0.0001