Expression of gerontogenes in neurons: A comparative genomic approach to studying the role of the nervous system in lifespan/aging part of Teaching Genomics at Small Colleges:Genomics Instructional Units Minicollection
A representative student-generated protein similarity tree for the gerontogene, spe-26 This 4-5 week laboratory exercise is ideal for an intermediate or more advanced undergraduate level course in neuroscience and behavior or even evolutionary biology. This laboratory module has students explore the role of the nervous system in aging and lifespan using genetic mutants of C. elegans. Gerontogenes are genes that influence lifespan in many organisms, including nematodes, insects and mammals. An intriguing question in evolutionary biology is what function is served by gerontogenes. Are these genes actually regulating aging? Or, are they involved in other cellular or physiological processes and influence aging/lifespan only indirectly (via pleiotropic effects)? Students use a bioinformatic approach to identify candidate gerontogenes in C. elegans. They select a gene to become "expert" on based on primary research articles that we have discussed in class. They then take a comparative genomic approach by identifying orthologs of candidate genes in other organisms and explore evolutionary relationships by sequence alignment and phylogenetic tree construction (making a protein sequence similarity tree). Students design and carry out a behavioral experiment, such as a thermotolerance test, based on literature-based exploration, that tests aspects of candidate gene function in behavior and conduct a behavioral screen of mutant nematodes. The laboratory culminates in a presentation, along with a scientific manuscript, that integrates the students' behavioral data, their literature-based work, as well as their protein sequence similarity analysis.