Significance
Calcium signaling and transport are fundamental to bone and dentin mineralization. Osteoblasts and odontoblasts transport large amounts of Ca2+ to the extracellular matrix. These cells maintain calcium homeostasis by spatially distributed calcium pumps and channels at the plasma membrane. STIM1 an ER Ca2+ sensor protein is an important component of the store-operated calcium entry (SOCE) process. In this study, we examined the role of STIM1 during the differentiation of dental pulp stem cells into functional odontoblasts and formation of mineralized dentin matrix. Stimulation of these cells with DMP1, a key regulatory protein in matrix mineralization, stimulates STIM1-mediated release of ER Ca2+ and SOCE activation. Silencing of STIM1 impairs signaling events, release of exosomes containing matrix proteins and matrix mineralization.
Statement of significance
Calcium signaling and transport are fundamental to bone and dentin mineralization. Osteoblasts and odontoblasts transport large amounts of Ca2+ to the extracellular matrix. These cells maintain calcium homeostasis by spatially distributed calcium pumps and channels at the plasma membrane. STIM1 an ER Ca2+ sensor protein is an important component of the store-operated calcium entry (SOCE) process. In this study, we examined the role of STIM1 during the differentiation of dental pulp stem cells into functional odontoblasts and formation of mineralized dentin matrix. Stimulation of these cells with DMP1, a key regulatory protein in matrix mineralization, stimulates STIM1-mediated release of ER Ca2+ and SOCE activation. Silencing of STIM1 impairs signaling events, release of exosomes containing matrix proteins and matrix mineralization.