Transcriptome analysis reveals genes differentially expressed and enriched in response to gregariousness in Galleria mellonella waxworms

Abstract Insects represent an enormous group of organisms with an extraordinary array of identified species, and others yet to be identified, habiting the most diverse regions. Likewise, insects present different behaviours depending on their needs, adapting their life cycles. An example is gregariousness, an aggregation behaviour common, but not limited, to social insects. One reported mechanism that underlies gregarious behaviour is growth promotion, especially among insect larvae. In this study, waxworms of Galleria mellonella (Lepidoptera: Pyralidae), a worldwide distributed moth, were used due to their gregarious behaviour. An exploratory RNA‐seq approach was performed in order to identify transcriptional responses upon gregariousness. Results indicate upregulation of a greater number of genes when they are gregarious compared with individualized waxworms. Enrichment analysis suggests distribution of genes across biosynthesis of amino acids and carbon metabolism pathways with high significance. Key differentially expressed genes, such as a general odorant‐binding protein 2, might indicate specific roles for gregariousness in lepidopterans. This study deepened our understanding of genes involved in waxworms aggregation, with potential targets in metabolism, defence and/or communication.