qPCR for second year undergraduates: A short, structured inquiry to illustrate differential gene expression

We describe a structured inquiry laboratory exercise that examines transcriptional regulation of the NOS2 gene under conditions that simulate the inflammatory response in macrophages. Using quantitative PCR and the comparative CT method, students are able determine whether transcriptional activation of NOS2 occurs and to what degree. The exercise is aimed at second year undergraduates who possess basic knowledge of gene expression events. It requires only 4-5 hr of dedicated laboratory time and focuses on use of the primary literature, data analysis, and interpretation. Importantly, this exercise provides a mechanism to introduce the concept of differential gene expression and provides a starting point for development of more complex guided or open inquiry projects for students moving into upper level molecular biology, immunology, and biochemistry course work.