The cytoskeleton in the biology of bone cells

Publisher Summary This chapter discusses the cytoskeleton in the biology of bone cells. The skeleton is a highly specialized and composite tissue, composed of cells of diverse origin and of an extracellular mineralized matrix. The skeleton provides structural support, protects soft tissues of the organism and blood-forming marrow cells, serves as a calcium reservoir and maintains mineral homeostasis. These multiple functions can be ensured by two main properties, the structure and organization of the porous trabecular bone and compact cortical bone, and the continuous replacement of the old bone by a new matrix during the bone remodeling process. During this process, the calcified bone matrix is continuously replaced due to the activity of bone resorbing cells, the osteoclasts, and of bone forming cells, the osteoblasts. These processes are dependent on the recruitment and activity of cells of the osteoclastic and osteoblastic lineages, and are controlled by several hormonal agents and growth factors.