Eusociality in insects has evolved independently many times. One of the most notable characteristics of eusociality is the reproductive division of labor. In social insects, the reproductive division of labor is accomplished by queens and workers. Transcriptome analyses of queens and workers have been conducted for various eusocial species. However, the genes that regulate the reproductive division of labor across all or multiple eusocial species have not yet been fully elucidated. Therefore, we conducted a meta-analysis using publicly available RNA-sequencing data from four major groups of social insects. In this meta-analysis, we collected 258 pairs (queen vs. worker) of RNA-sequencing data from 34 eusocial species. The meta-analysis identified a total of 20 genes that were differentially expressed in queens or workers. Out of these, 12 genes have not previously been reported to be involved in the reproductive division of labor. Functional annotation of these 20 genes in other organisms revealed that they could be regulators of behaviors and physiological states related to the reproductive division of labor. These 20 genes, revealed using massive datasets of numerous eusocial insects, may be key regulators of the reproductive division of labor.
Simple SummarySocial insects form complex, sophisticated societies in which members work cooperatively. Ants, bees, wasps, and termites are examples of social insects. The key characteristic of their structured societies is the reproductive division of labor. The queens reproduce within the nests, whereas workers engage in other tasks for colony development. Although gene expression profiles associated with the reproductive division of labor have been revealed for each social species, the existence of core regulatory genes commonly shared by all or multiple social insects is largely unknown. To address this issue, we conducted a meta-analysis by collecting and reanalyzing massive amounts of data from social bees, social wasps, ants, and termites. We identified 20 genes with queen- and worker-biased expression. Twelve of these genes have not been previously associated with reproductive division of labor. The expression of these genes is likely necessary for social insects to exhibit reproductive division of labor.
