An expression system of channelrhodopsin-2 driven by a minimal Arc/Arg3.1 promoter and Tet system was developed in human neuroblastoma cells

Advances in neuroscience have relied on the development of techniques that examine neuronal cell activities. One major challenge involves the limitations in labeling and controlling neuronal activities relating to the cell's activation state. In this study, the modified human codon-optimized channelrhodopsin-2 photoreceptor hChR2(C128S) was integrated into function with inducible gene expression methods and materials: the Tet system and the highly efficient minimum promoter of Arc/Arg3.1. The system successfully expressed the target fusion gene exclusively in activated SH-SY5Y human neuroblastoma cells while maintaining the essential characteristics of ChR2. The expression of the channelrhodopsin construct was observed, while the expression duration was refined by treatment with doxycycline. The optogenetic construct here tested the application of the minimum Arc/Arg3.1 promoter, an advanced immediate-early gene promoter, for the expression of the channelrhodopsin gene. Along with its noninvasive nature, this expression system promises to serve dual functions as a cell activity indicator and cell actuator, creating the possibility for researchers to precisely label cells according to their activation state and control the activities of specific neuronal cell populations.