A Versatile Semester-Long Course-Based Undergraduate Research Experience using Optogenetics and RNAi to Identify Genes Important for Synapse Function.

Compared to traditional teaching laboratory activities, course-based undergraduate research experiences (CUREs) can increase student engagement and confidence, improve scientific literacy, enhance critical thinking, and promote accessibility in STEM. Here we describe a versatile CURE for an upper-level Neurobiology course that incorporates genetic, molecular, cellular, and behavioral experiments into a semester-long investigation to identify genes important for glutamate synapse formation or function in C. elegans. Following introduction to the CURE approach and basic C. elegans techniques, students construct their own low-cost optogenetics rigs, which we describe in detail here, to activate a mechanosensory escape reflex via photostimulation. They then perform a small-scale RNAi screen with this light-activated behavioral readout. Once a gene of interest is identified, students submit a proposal to investigate the role of this gene in nervous system function and spend the rest of the semester carrying out follow-up experiments using mutant strains. We also describe ways in which this CURE can be modified depending on the pedagogical objectives, availability of materials, or research interests of the instructor. Participating in this lab significantly enhanced students' abilities to see themselves as STEM professionals and prompted students to report substantial gains in skills critical for entry into and success in graduate and medical schools. In addition to the benefits CUREs provide to students, faculty benefit from the generation of preliminary data and training of students for potential independent research projects.