Osiris Gene Expression in Harvester Ants and German Cockroaches

Moataz Noureddine Earlham College, Swati Pant Earlham College
Faculty Sponsor(s): Chris Smith Earlham College
The Osiris gene family is a cluster of genes present in all insect genomes and is the result of multiple ancient duplications of a single ancestral gene (the cluster typically includes twenty Osiris genes). The order of the genes is highly conserved among insects, and deletions of the cluster are fatal. Our experiment focused on the expression of multiple Osiris genes in Pogonomyrmex barbatus, harvester ants, and Blattella germanica, the german cockroach. The choice of these two species is strategic and allowed us to examine expression patterns in organisms differing in development and lifestyle. The ants have complete metamorphosis and are social while the cockroaches have incomplete metamorphosis and are solitary. We assayed gene expression in whole bodies spanning developmental stages using quantitative polymerase chain reaction (qPCR). There are transient peaks in transitional stages to adulthood in both species, the last nymphal instar of the cockroach and the pupal stage for roaches and ants, respectively. In the ants, the expression peak only occurred in workers. Together, these data suggest a role of Osiris genes in the transition to adulthood, and this is conserved across hemi- and holometabolous insects. The worker-only peak in ants suggests a possible role for these genes in suppressing typical adult characteristics, such as those present in queens.
Oral Presentation

When & Where

01:30 PM
Jordan Hall 172