The Drosophila 7-Pass Transmembrane Glycoprotein BOSS and Metabolic Regulation

Glucose is a key carbohydrate for the majority of living organisms. In animals, plasma glucose levels must be strictly regulated and maintained at proper levels. Abnormal upregulated glucose levels lead to various human metabolic disorders such as diabetes or obesity. In the diabetic state, protein glycation occurs, producing nonenzymatic products that are thought to be causative compounds for the disease. During evolution, animals developed sensing and regulatory mechanisms to maintain constant levels of body glucose levels. How organisms respond to extracellular glucose and how glucose controls nutrient homeostasis, however, have remained uncertain. Recently, we identified bride of sevenless (BOSS) in Drosophila as a glucose-responding membrane receptor. In this chapter, we summarize the utility of Drosophila as a model organism for studying conserved mechanisms of glucose and triacylglycerol (energy) homeostatic metabolism through the 7-pass transmembrane glycoprotein BOSS, which carries N-linked carbohydrates.