NEW YORK (GenomeWeb) – Vanderbilt University announced last week that the National Science Foundation has awarded Associate Professor Seth Bordenstein a $950,000 grant to study genes involved in regulating bacterial infections that are passed between insect generations.
The grant will allow a comparative study of two species of wasps that differ in the microbial densities of an infection by bacteria in the genus Wolbachia. Wolbachia have carved out a niche by infecting the germ cell tissues of almost 40 percent of all insect species, Bordenstein told GenomeWeb.
The study may help answer several questions about which genes are involved in controlling those infections. The consequences of infection are mixed: Wolbachia can distort sex ratios in wasps but may also have a positive effect on the insect immune system.
"How has the host responded to infections in the germ cells? What are they doing to keep infection at bay?" Bordenstein said. He added that any genes discovered in the study would likely be involved in insect immunity or development.
The study will use a forward genetic analysis involving quantitative trait loci mapping to find the regions hosting genes that contribute to controlling the differences in infection. "Preliminary analysis suggests there are two regions, so it's a pretty simple trait," Bordenstein said.
Once the regions are found, the lab will use RNA-seq to determine differences in gene expression, yielding gene candidates that could be responsible for the phenotypic difference in bacterial density between the two wasp species. Finally, RNA interference-mediated knockdowns of candidate genes will suggest the genes responsible for the difference.
Bordenstein pointed to Toll-like receptors as an example of the kind of gene that could have significance for the understanding of human genetics and health. Those genes were discovered in fruit flies, but are fundamental to human immunity. "There may be more genes like that waiting to be discovered," he said.