Abstract: The specification discloses materials and methods for screening and identifying reagents, which modulate Norrin activity as it relates to Wnt pathway signaling. Preferably, agents identified thereby modulate bone remodeling and/or lipid levels, and can be Norrin mimetics and Norrin agonists, as well as other agonists and mimetics of the LRP5/Norrin/Frizzled4 complex.

Abstract: The present invention provides reagents, compounds, compositions, and methods relating to novel interactions of the extracellular domain of LRP5, HBM (a variant of LRP5), and/or LRP6 with Dkk, including Dkk-1. The various nucleic acids, polypeptides, antibodies, assay methods, diagnostic methods, and methods of treatment of the present invention are related to and impact on Dkk, LRP5, LRP6, HBM, and Wnt signaling. Dkk, LRP5, LRP6, HBM, and Wnt are implicated in bone and lipid cellular signaling. Thus, the present invention provides reagents and methods for modulating lipid levels and/or bone mass and is useful in the treatment and diagnosis of abnormal lipid levels and bone mass disorders, such as osteoporosis.

Abstract: The invention discloses compositions, compounds, apparatuses and methods of using them to study bone mineralization and identify agents that regulate bone mineralization. Methods of using bone mineralization gene profiles and signatures for compound screening and research are also disclosed. Reagents for modulating bone mineralization are provided for both therapeutic and research usage.