The SOST gene was initially identified as the gene responsible for two sclerosing bone dysplasias: sclerosteosis and van Buchem disease . Sclerostin is a member of the Dan family of glycoproteins, which are characterized by a cysteine-knot motif . It negatively regulates canonical Wnt signaling pathways by binding to low-density lipoprotein receptor-related protein (LRP) 5/6, thereby suppressing osteoblast differentiation and function .
Sclerostin’s primary function is to inhibit the Wnt signaling pathway, which is crucial for bone formation . By binding to LRP5/6, sclerostin prevents the activation of Wnt signaling, thereby inhibiting osteoblast activity and bone formation . This regulation is essential for maintaining bone homeostasis and preventing excessive bone formation .
The inhibition of sclerostin has been explored as a therapeutic strategy for treating osteoporosis Romosozumab, a specific anti-sclerostin antibody, has been developed to inhibit sclerostin-LRP5/6 interactions, thereby activating Wnt signaling and promoting bone formation . Clinical studies have demonstrated the efficacy of romosozumab in increasing bone mineral density and reducing osteoporotic fractures .
Recombinant human sclerostin is produced using recombinant DNA technology, which involves inserting the SOST gene into a suitable expression system to produce the protein in large quantities . This recombinant form is used in various research and clinical applications to study the protein’s function and develop therapeutic interventions .
Recent advancements in the study of sclerostin include the development of second-generation immunoassays for measuring circulating sclerostin levels . These assays aim to overcome methodological obstacles and provide more accurate measurements of sclerostin levels in clinical settings . Additionally, the three-dimensional structure of human sclerostin has been generated using the AlphaFold Protein Structure Database, providing insights into its molecular interactions and functional properties .