STURTEVANT, MARK A.: A Laboratory Exercise for Analysis of Gene Expression and Function

An important goal in life science teaching is to provide students with hands-on experiences in cellular and molecular biology concepts and techniques. This poster describes a three-step laboratory exercise that allows students to analyze expression and function of genes during development of Drosophila embryos. First, students visualize the expression patterns of different segmentation genes in embryos by staining for expression of reporter genes. Second, students identify the role these genes during normal development by comparing phenotypes of normal embryos with embryos that are mutant for each gene. Third, students identify probable characteristics of the protein encoded by each of the studied genes, such as whether they appear to code for a transcription factor or a secreted signal. This is done by tracking down primary literature and internet database resources for similar genes found in other animals. With this information, students formulate specific models about the function of the studied genes during development of Drosophila. The activities carried out require students to collaborate, and to integrate information at the levels of anatomy and genes. The activities are also a practical experience for students since they are based on those used by researchers to characterize the function of newly discovered genes. Other matters that students discover during this exercise are that homologs of the studied Drosophila genes are important for vertebrate development, and that research in these areas has provided insight into certain medical conditions in humans including cancer.