DMP1 and MEPE expression are elevated in osteocytes after mechanical loading in vivo: theoretical role in controlling mineral quality in the perilacunar matrix

DMP1, highly expressed in osteocytes, is involved in local effects on bone mineralization as well as systemic phosphate metabolism. DMP1 protein is localized in the lacunar and canalicular walls of osteocytes and the gene responds rapidly to mechanical stimulation. Here we propose that one major role of DMP1 is in maintaining integrity and stiffness of the lacunar and canalicular walls. The global knock-out of the DMP1 gene results in mice that have canalicular walls which are irregular in shape and cell processes which are almost twice the normal diameter (McKee, Harris and Feng, unpublished).