Lipid Mobilization and Acyl-Coenzyme A Dehydrogenase Abundance in the Postpharyngeal Gland of a Leaf-Cutting Ant

Abstract

The postpharyngeal gland (PPG) in ants has a central role in lipidaccumulation. Our objective was to investigate whether the PPG ofworkers of the leaf-cutting ant Atta sexdens rubropilosa (F.) performslipid mobilization to the hemolymph, and to verify whether lipidsin gland cells are in part oxidized to acetyl-CoA. Increased levelsof fatty acids were observed in both the PPG and the hemolymphafter 48 h of lipid supplementation. In contrast, after 120 h of lipidsupplementation, fatty acid levels were reduced in the PPG andsignificantly increased in the hemolymph. The gland cells of the PPGof workers supplemented with lipids exhibited a high amount of Acyl-CoA dehydrogenase, and the lipids were in part β-oxidized to Acetyl-CoA. These findings suggest that the PPG of A. sexdens rubropilosaworkers mobilize fatty acids from their gland cells to the hemolymph.Further work will be needed to elucidate lipid transport from thehemolymph to other organs in this organism.