Dopamine Enhances Surface Glial Glycolysis via Acetylcholine and Insulin/Insulin-Like Growth Factor Signaling in Honeybee
Glycolysis plays a crucial role in maintaining neuronal functional homeostasis and is regulated by neuroendocrine signals, particularly dopamine. However, the underlying regulatory mechanisms remain poorly understood. Here, we investigate dopamine driven neuroendocrine control of glial glycolysis in honeybee through integrated metabolomics and single-cell transcriptomics. Activation of dopamine 2 receptors(D2R) via bromocriptine significantly enhanced glycolytic flux in worker bees, as evidenced by elevated glucose levels, accumulation of glycolytic intermediates, and suppression of pentose phosphate pathway metabolites. Single-cell and single-nucleus RNA sequencing revealed that acetylcholine (ACh) secreted by Kenyon cells (KCs) is a critical node in dopamine-regulated glycolysis. Bromocriptine treatment reduced ACh secretion and directly enhanced surface glial (SG) specific glycolytic gene expression, while also increasing insulin signaling from cortex glial to surface glial. Our findings uncover a dual regulatory mechanism, in which the dopamine-ACh axis coordinates with IIS signaling to orchestrate metabolic plasticity in glial through cell type-specific precision. This study provides insights into how social insects integrate neuroendocrine signals to optimize energy metabolism and highlights the role of ACh in this process. Overall design: We employed single-nucleus RNA sequencing (snRNA-seq) using the 10x Genomics platform to investigate the effects of bromocriptine, a dopamine agonist, on the neural transcriptome of honeybee (Apis mellifera) forager brains. For this study, foraging bees were divided into two experimental groups: one treated with bromocriptine and the other with water as a control. Brains from 15 foragers per group were dissected and processed for snRNA-seq to resolve cell-type-specific transcriptional responses. This work represents the first application of single-nucleus transcriptomics to explore neuropharmacological modulation in honeybees, offering unprecedented insights into how dopaminergic signaling influences neural plasticity and foraging-related behaviors in a eusocial insect model. By comparing bromocriptine-exposed and control groups, our findings may advance understanding of conserved neuromodulatory pathways and their roles in social insect behavior