Because of deleterious effects on host survival and reproductive success, parasites impose strong selection pressures on hosts for increased or even complete resistance to parasite infection. However, individuals within a host population in nature always exhibit substantial variations in resistance to infection. The genetic mechanisms for this interesting phenomenon are not clear. This research will use the rat tapeworm parasite and its intermediate host, the red flour beetle, to test the hypothesis that host resistance to parasite infection is associated with fitness costs. In particular, this project will identify the genes conferring beetle resistance to the tapeworm parasites using genetic mapping and bioinformatics techniques. The work will also determine the genes' roles in host fitness by using molecular methods that remove and reposition target genes and then infer effect by measuring the resultant consequences to essential biological functions.
This project will provide important insights into the molecular genetic basis and the evolutionary constraints of host resistance to parasite infection, and make an important contribution to evolutionary biology because it examines common assumptions made about the evolution of resistance. The project has broader implications for vector-borne disease control, agriculture, and conservation. The idea of using genetic engineering methods to control malaria and Dengue has been in discussion for a decade. The issue of resistance evolution is particularly relevant for the development of novel strategies to spread parasite-resistance genes into natural vector populations. The materials and methodologies developed from this project will be integrated into the education and training for undergraduate and graduate students and high school teachers.
