SPARC-related modular calcium-binding protein 1, also known as secreted modular calcium-binding protein 1 and SMOC1, is a member of the SPARC family. SMOC1 is widely expressed in many tissues with a strongest signal in ovary. It contains two EF-hand domains, one Kazal-like domain and two thyroglobulin type-1 domains. Extracellular matrix proteins have been implicated in the regulation of osteoblast differentiation of bone marrow derived mesenchymal stem cells (BMSCs) through paracrine or autocrine mechanisms. SMOC1 is a regulator of osteoblast differentiation of BMSCs. SMOC1 is highly expressed and secreted in BMSCs stimulated with osteogenic medium (OSM). SMOC1 and SMOC2 are matricellular proteins thought to influence growth factor signaling, migration, proliferation, and angiogenesis. SMOC1 and SMOC2 may mediate intercellular signaling and cell type-specific differentiation during gonad and reproductive tract development.