RUNX2 promotes and DHT antagonizes RANKL association with the osteoblast membrane. NeMCO/Rx2dox were treated for 48 hr with dox and/or DHT as indicated, and endogenous RANKL (a and b) or transiently expressed GFP-RANKL (c and d) were imaged by indirect and direct immunofluorescence, respectively. (a and c) Representative micrographs (Scale bar = 50 μm), with arrows marking membrane-associated RANKL. (b and d) Percentage of cell perimeter containing RANKL or GFP-RANKL was determined for ≥10 randomly selected cells per condition (Mean ± SD; n ≥ 10; *p < 0.05). C, control; D, dox; A, DHT; DA, dox plus DHT