Bone and Cartilage Cellular and Molecular Biology

The Molecular and Cell Biology component of the VORL investigates many causes of injury to both bone cells and cartilage tissue, such as osteoarthritis and bone fractures, as well as the pathway of cascading effects that occur in the microenvironment of the cells. Some of the goals of these research projects are to make detailed observations of the severity of injury in respect to differentiation amongst multiple variables and to discern points along these pathways that can be altered to create an overall positive impact in reducing the effects of these injuries and diseases.

Understanding the influence of the biophysical environment on normal cell biology has been our central focus for some time. Many of the mechanical stimuli osteoblasts respond to, and the downstream signaling events that are initiated have been identified. What is still unknown, however, is the identity of a cell-bound mechanosensor or mechanosensory complex, which would initiate the conversion of a localized biophysical signal into an intracellular signaling response. We are investigating the role of annexins, calcium-dependent phospholipid-binding proteins, as a possible mechanosensors. We are also looking at the role of lipid rafts in mechanosignaling since annexins can localize to these membrane regions, which may be the initiation points of mechanosensing.