Modulation of Synapsin I Gene Expression in Rat Cortical Neurons by Extracellular Matrix

Here the authors have attempted to dissect the complex interaction between the genetic program and environmental cues involved in neuronal differentiation. In this study, neurons isolated from fetal rat brain (embryonic day 16) cortices were cultured on six different extracellular components, such as laminin-111, collagen, and poly-D-lysine in a chemically defined, neuron-specific medium. Among the ECM components tested, laminin allowed both firm attachment and extensive neurite outgrowth from neuronal cell bodies. Furthermore, laminin strongly increased gene expression the synapse-specific protein,  Synapsin I, a well-known central marker for neuronal differentiation. These results highlight the significance of extracellular matrix components, particularly laminins, for the extension of neurite networks and neuronal differentiation of primary cortical neurons.