Growth and differentiation of a long bone in limb development, repair and regeneration

摘要

Repair from traumatic bone fracture is a complex process tinat includes mechanisms of bone development and bone liomeostasis. Thus, elucidation of the cellular/molecular basis of bone formation in skeletal development would provide valuable information on fracture repair and would lead to successful skeletal regeneration after limb amputation, which never occurs in mammals. Elucidation of the basis of epimorphic limb regeneration in amphibians would also provide insights into skeletal regeneration inmammals, since the epimorphic regeneration enables an amputated limb to re-develop the three-dimensional structure of bones. In the processes of bone development, repair and regeneration, grov/th of the bone is achieved through several events includingnot only cell proliferation but also aggregation of mesenchymal cells, enlargement of cells, deposition and accumulation of extracellular matrix, and bone remodeling.