The GAP43 gene in neuroblasts is upregulated in response to cell seeding density.

The cell in multicellular organisms are capable of sensing and responding to various types of extracellular stimuli. Recent studies have highlighted the importance of not only biochemical stimuli but also mechanical stimuli in modulating cellular behavior. Mechanical stimuli include substrate stiffness, shear stress, tensile force, and compressive strain, all of which have been implicated in the regulation of gene expression, proliferation, and differentiation. In this study, we investigated the impact of compressive strain by cell seeding density on gene expression in Neuro2A cells, a mouse neuroblastoma-derived neuronal cell line. Specifically, we focused on the expression of Cyclin D1, a well-established proliferation marker, and GAP43, a marker associated with neuronal differentiation. By culturing Neuro2A cells at different cell densities, we found that high cell density upregulated the GAP43 gene but not the Cyclin D1 gene. This result suggests that cell density affects neuronal differentiation through GAP43 gene expression.