Runx1–regulated genes related to osteoclast differentiation. Bone marrow cells isolated from either 8-week-old Runx1F/F or CD11b-Cre;Runx1F/F mice were cultured in the presence of 30 ng/mL M-CSF with various doses of RANKL (0, 10, and 30 ng/mL) for 2 days. Total RNA, extracted from cells, was used to measure gene expressions of v-ATPase D2 (A), CatK (B), MMP9 (C), CTR (D), OSCAR (E), NFATc1 (F), and cFos (G). The relative quantification of target gene expression was normalized to the expression of a housekeeping gene, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), for each sample using the ΔΔCT method. Results are expressed as means ± SE (n = 3) and are representative of 3 replicate experiments. *, P < .05 vs Runx1F/F mice within the same treatment; $, P < .1 vs Runx1F/F mice within the same treatment; #, P < .05 vs M-CSF alone within Runx1F/F mice; @, P < .05 vs M-CSF plus 10 ng/mL RANKL within Runx1F/F mice.