The influence of juvenile hormone on the expression of a major royal jelly protein in Apis mellifera

The reproductive ground plan hypothesis (RGPH) has identified several genes, proteins, and hormones that have been repurposed to suit the social organization in a colony. Honey bee workers experience age polyethism, where they transition from nursing tasks to foraging tasks. Unlike reproductive individuals, juvenile hormone (JH) in sterile workers acts as a pacer for age polyethism that triggers foraging behavior and other task-related physiological changes. High JH titers are associated with expression of nutritionally linked genes and in this study we sought to identify candidate genes that fit into the RGPH. Our first objective was to conduct an exploratory transcriptome analysis to identify nutritionally linked genes between the brains of nurses and foragers, and differential gene expression analysis revealed 89 differentially expressed genes between the two. Bioinformatic analysis was used to identify the gene of interest, major royal jelly protein 1 (mrjp1),which is expressed higher in nurses than foragers. The gene is associated with the synthesis of royal jelly and gene annotation revealed that major royal jelly protein 1 (mrjp1) could be correlated with hormonal titers. Bioassays involving topical applications of JH analogs were used to determine the influence of JH on the expression of mrjp1. Our interest in JH stems from the use of its analogs in pesticides, so we aim to apply our methods to bettering conservation practices in addition to furthering our understanding of foraging behavior and the physiological factors that influence it.