The regulation of trehalose metabolism in insects.

Trehalose is a non-reducing disaccharide comprising two glucose molecules. It is present in high concentration as the main haemolymph (blood) sugar in insects. The synthesis of trehalose in the fat body (an organ analogous in function to a combination of liver and adipose tissue in vertebrates) is stimulated by neuropeptides (hypertrehalosaemic hormones), released from the corpora cardiaca, a neurohaemal organ associated with the brain. The peptides cause a decrease in the content of fructose 2,6-bisphosphate in fat body cells. Fructose 2,6-bisphosphate, acting synergistically with AMP, is a potent activator of the glycolytic enzyme 6-phosphofructokinase-1 and a strong inhibitor of the gluc…