Proteome-metabolome profiling of wax gland complex reveals functional changes in honeybee, Apis mellifera L

Wax gland complex (WGC) serves as the primary generator of beeswax; however, the dynamic biological function in wax secretion remains unclear. To elucidate the developmental mechanism of WGC, we conducted a comprehensive analysis to reveal the variations in proteins and metabolites among the newly emerged bee (NEB), wax-secreting bee (WSB), and overaged bee (OAB). We identified 3,295 proteins and 159 metabolites in WGC. Specifically, NEB elevated the expression of ribosomal proteins for preparing the glandular organ. While WSB promoted the size of epidermal cells and oenocytes, the enrichment of fatty acids and energy metabolism in WSB suggested a strong ability in wax synthesis. In OAB, disorganized wax tubules, and up-regulated cysteine proteases reflected the gland degeneration. These findings highlight the dynamic changes in the level of molecule and morphological structure in WGC, offering valuable insights into the development and mechanism of wax secretion in honeybees and other wax insects.