Unraveling the dynamics of osteoblast differentiation in MC3T3-E1 cells: Transcriptomic insights into matrix mineralization and cell proliferation

Unraveling the intricacies of osteoblast differentiation is crucial for advancing our comprehension of bone biology. This study investigated the complicated molecular events orchestrating osteoblast differentiation in MC3T3-E1 cells, a well-established in vitro culture model. Employing longitudinal RNA-sequencing analysis, we explored transcriptomic changes at the pivotal time points of 0, 1, 4, 7, 10, 14, and 21 days and categorized osteogenic differentiation into proliferation, matrix maturation, and mineralization stages. Notably, we observed a simultaneous increase in matrix mineralization and cell proliferation during the mineralization stage, accompanied by a positive correlation between proliferation-associated genes and those enriched in ossification. Additionally, we identified the presence of proliferating cells over the mineralizing matrix layers. These results could serve as a model for understanding the principles by which bone lining cells are formed on the calcified bone matrix and the mechanism by which new osteoblasts are recruited during the bone remodeling process.