Knockdown of Myo9b causes a Rho-dependent loss of bone resorptive capacity.

A, siRNA-mediated knockdown of Myo9b diminishes resorptive capacity of osteoclasts in a Rho-dependent manner, as demonstrated by photomicrographs of resorption pits on ivory slices (top). Scale bar  = 50 µm. Quantification of the surface area of each pit (pit area) and total resorbed surface area (total resorption) are shown graphically below. #: P<0.05; *: P<0.005; N.S.  =  not significant. B, Knockdown of Myo9b does not significantly affect osteoclast number or the ability of cells to form sealing zones on bone, as indicated by photomicrographs of phalloidin-labeled sealing zones (top) and enumeration of cell number and sealing zone number and size (bottom).