Study on the molecular mechanism of colony strength of Apis cerana cerana based on transcriptomics

Apis cerana cerana exhibits highly sensitive olfactory capabilities, resistance to cold and heat, and strong foraging abilities. It plays a critical role in sustaining ecosystem stability and enhancing agricultural productivity and economic yields of farmers in mountainous areas. Given that colony strength is fundamental to the reproductive capacity and productivity of Apis cerana cerana, maintaining strong colonies is essential for enhancing their disease resistance, survival, and productivity. In this study, Apis cerana cerana in Zizhou County of the Lvliang Mountains was used as the research object. To investigate the molecular mechanisms underlying colony strength differences, we performed transcriptome sequencing on the head and thorax of worker bees from strong and weak colonies, with the goal of identifying differentially expressed genes and regulatory pathways associated with sensory perception in the head and energy metabolism in the thorax.The results showed that 751 differentially expressed genes were identified between the heads of strong and weak colonies, primarily enriched in odorant-binding protein, royal jelly major protein, taste receptor gene, olfactory receptor family genes, and others. A total of 852 differentially expressed genes were identified between the thorax of different colonies, mainly enriched in cytochrome P450, zinc finger protein, serine / threonine kinase, and cytochrome C oxidase family genes. Gene function enrichment analysis revealed that the strength of colony is associated with growth and immune response pathways, such as macromolecular biosynthesis, organic nitrogen biosynthesis, and ribosome metabolism in the head of bees, as well as energy metabolism pathways, including sugar metabolism, lipid metabolism, and amino acid metabolism in the thorax of bees, which have been previously associated with extended lifespan in other insect models, suggesting a potential link to individual longevity in strong colonies. The strength of the colony is significantly related to energy metabolism, immunity, heat stress, and phosphorylation regulation, Worker bees in strong colony exhibit stronger antioxidative stress, energy metabolism, resistance to external environmental temperature and harmful substances, and anti-inflammatory and antibacterial capabilities.