Fig. 2

l-CaD expression levels alter the actin ring structures in OCs associated with their mineralized matrix degradation. a Actin ring formation labeled with rhodamine phalloidin in RANKL-induced OCs treated with control siRNA (top, siCtr) and si-l-CaD (bottom). The area of interest (AOI) for the actin ring (highlighted in indigo blue) in OCs (delimited by a line of green circle) as shown on the left was measured by using Image-Pro Plus computerized software. Quantitative analyses of the optical density for the actin ring forming area in each cell with si Ctr and si-l-CaD are shown at the bottom. b Actin ring formation in RANKL-induced OCs transfected with EGFP controls (EGFP, top) or EGFP-l-CaD (l-CaD, bottom). Quantitative analyses of the optical density for the actin ring forming area in each cell transfected with EGFP and EGFP-l-CaD are shown at the bottom. c Resorption pit assay showing the l-CaD dependent changes of resorption pit forming area in RANKL-induced OCs treated with si Ctr or si-l-CaD, or transfected with EGFP control and EGFP-l-CaD vectors. Resorption pit assay in cells without RANKL induction was shown on the left column. Calibration scale as indicated. In a, b, and c the values are the mean ± SEM (n = 6), with * indicating a significant difference compared to the si Ctr-treated or EGFP-transfected cells, respectively