During prolonged flight, locusts predominantly utilize lipids for energy generation. Lipid stores are mainly located in the fat body. Flight is accompanied by release of adipokinetic hormones from the corpora cardiaca. Under the influence of these hormones, fat body triacylglycerol is converted to diacylglycerol, which is released into the haemolymph. This release requires the presence of specific lipoproteins. The lipid mobilizing effect of adipokinetic hormone on the fat body is attended by the association of a high density lipophorin and a non-lipid containing protein, both already present in the haemolymph, and the increased amount of released lipid to form a new lipoprotein, low density lipophorin. Upon delivery of the lipid to the flight muscles, participating proteins dissociate again and can be reused for lipid uptake at the fat body (lipoprotein shuttle system). The flight-specific metabolic systems could be starting-points for new devices in control strategies.
