View Program - 63rd Annual Drosophila Research Conference

The innate immune response is an evolutionarily conserved process that is essential for host survival in all multicellular organisms. As individuals age, immune functions begin to decline, or immunosenesce, reducing one’s ability to fight infections, posing a serious risk to human health. The way that age affects the immune response can vary greatly among individuals, and although this variation has a significant heritable component, the genes responsible for this variation are not known. Previous data using 12 inbred Drosophila melanogaster lines from the Drosophila Genetic Reference Panel (DGRP) found that the genes implicated in clearing an infection were different between young and aged flies. The goal of this project is to identify genes that regulate age-specific immune responses to better understand the mechanisms that give rise to immunosenescence. Currently, standard bacterial clearance assays and genome wide association tests (GWAs) are being performed using the 192 DGRP lines available. To assess the ability of each line to clear an infection, one and five week old virgin females are injected with 18.4nL of an E. coli solution at an OD₆₀₀ of 1.0+ 0.01. After 24-hours, the surviving flies are individually homogenized and plated on streptomycin LB/agar plates. The colony forming units per milliliter (CFU/mL) represents the phenotype of that individual and reflects the remaining bacteria in the fly. A GWAS will then be performed at both ages to identify candidate genes involved in clearance across ages. Those candidate genes will be the focus of future studies where the results could lead to improved therapeutic treatments in an aging population, providing age-appropriate drug targets to restore the immune function.

Identifying Candidate Genes and Genetic Networks that Influence the Age-specific Ability to Clear an Infection Using Genome Wide Association Tests (GWAs)