Lipogenesis from [14C]acetate during development of Ceratitis capitata

Lipogenesis from [¹⁴C]acetate has been precisely carried out during development of Ceratitis capitata. Acetyl-CoA carboxylase activity and fatty acid synthesis capacity were determined in vitro from eggs to 10-day adults; both activities exhibit a sharp peak in the larval stage and drop to a minimum value in the pharate adult stage. Fatty acids synthesized by the larvae were mainly incorporated into triglycerides, whereas fatty acids formed by the pharate adult homogenates were substantially recovered as phospholipids. Variations of the levels of labelled lipids reached by larvae fed on [¹⁴C]acetate at consecutive development ages (5, 6, and 7 days) parallel the changes that labelled lipids show in consequence of the metabolic behaviour of the 5-day-old larvae. Variations of the levels of the different lipid classes and patterns of specific radioactivity allow us to state some properties of the lipogenic system of the insect.