Intellectual Merit: Advantageous genes normally persist and predominate in populations, while deleterious genes disappear. However, some non-adaptive genes have found ways to counter the forces of natural selection and infiltrate populations; these are known as selfish genetic elements or selfish genes. Such elements are able to increase in frequency and spread through populations by employing genetic mechanisms that circumvent Mendel's laws of inheritance. A fascinating case is that of the Maternal-Effect Dominant Embryonic Arrest (Medea) elements in the red flour beetle, Tribolium castaneum. Heterozygous Medea females transmit a dominant-lethal factor to hatchlings, but the lethal effect is shut down in those progeny that inherit a Medea allele from either parent. Thus, each Medea allele encodes both a maternally loaded "poison" and an "antidote" expressed in the embryo. Little is known about how such elements function. Therefore, this project is aimed at discovering the molecular mechanism responsible for Medea's selfish behavior by using genetic and genomic tools to uncover the genes involved in self-selection.
Broader Impacts: This project will increase our understanding of how selfish genes escape natural selection and infiltrate populations. This knowledge could provide a new mechanism for transferring traits into pest populations to make them less problematic. The project includes several educational components. The PI is participating in an NSF Integrative Graduate Education and Research Traineeship (Genetic Engineering and Society: The case of transgenic pests) that is focused on training students in technologies used for manipulation of pest genomes as well as methods needed to assess the environmental and sociocultural appropriateness of specific products of these genetic manipulations. This research will be integrated directly into IGERT courses and research of IGERT graduate fellows. The project also includes activities that will provide undergraduates from underrepresented groups with an opportunity to participate in cutting-edge functional genomic research. Moreover, this research will be widely disseminated through outreach events by the PI and IGERT students to raise public awareness about the utility of transgenic technologies.
