IVISc-L: A quick and simple in vivo assay to study the regulation of gene expression
Several methods are available to study the regulation of gene expression at cellular and molecular levels. Adaptation of these methods in vivo is cumbersome and often requires animal sacrifice. Here, we report an assay (IVISc-L, In Vivo Imaging of Subcutaneous Luminescence) to study gene regulation in vivo. This assay involves subcutaneous injection of a plasmid DNA encoding firefly luciferase, whose expression is under the regulatory mechanism to be investigated. We could infer its regulated expression by detecting the subcutaneous luminescence using an in vivo imaging system. Using this assay, we have demonstrated the regulation of gene expression mediated by a promoter, micro-RNAs, stop codon readthrough, and rare codons. This minimally invasive assay does not require animal sacrifice or any tissue extraction. The entire assay can be completed within 24 hours. Therefore, this assay will be useful in investigating the mechanisms of gene expression regulation, and screening molecules that can alter gene expression in vivo.