Recent progress of osteoactivin

Osteoactivin (OA) is a novel glycoprotein that was identificated from an animal model of osteosclerosis. Recent studies show that OA is expressed in bone,liver,and kidney with different levels,and takes many biological functions, such as osteoblast and osteoclast growth and differentiation, fibroblasts cell differentiation. OA plays an important role in bone anabolism by inducing the differentiation of osteoblast and osteoclast. But only a few studies reported the possible mechanism of OA ,such as induction of matrix metallo-proteinase(MMP)-3 expression through extracellular signal-regulated kinase signaling pathway in fibroblast cells, as well as a downstream regulator, involved in the regulation of bone morphogenetic protein (BMP) -2 on osteoblast differentiation and matrix mineralization. Investigating the mechanisms by which OA mediates its biological roles will open the door for developing novel therapeutic as well as diagnostic tools for various clinical conditions. Key words: Osteoactivin;  Osteoblast;  Osteoclast