Comparative transcriptome analysis of midgut of Bombyx mori under a sugar-supplemented diet

As an monophagous insect, the silkworm possesses a restricted feeding capacity. To investigate the impact of varying sugar concentrations on silkworm growth and development, transcriptomic analyses were conducted on the silkworm midgut. A total of 562 differentially expressed genes (DEGs) were identified, with down-regulated genes predominantly associated with starch and sucrose metabolism, fructose and mannose metabolism, galactose metabolism, and amino sugar and nucleotide sugar metabolism. Of particular interest was the gene GalE within the glucose metabolic pathway. Key findings included the up-regulation of GalE in the galactose metabolic pathway and its pivotal role in glucose metabolism and cell signaling. Additionally, the significance of GalE in nucleotide sugar balance and glycolipid/glycoprotein metabolism was highlighted. These alterations suggest that excessive sugar consumption may suppress the sugar metabolic pathway in silkworms. This study offers a comprehensive analysis of transcriptomic studies on high sugar intake in silkworms, providing insights into the effects of varying sugar concentrations on these organisms.