The biological significance of lipogenesis in Nasonia vitripennis

Parasitic wasps have long been thought to be unable to synthesise fatty acids de novo, but recent 13C-labelling studies have challenged this view. It remained unclear, however, whether the reported biosynthesis rates are of biological relevance. Here, we show in Nasonia vitripennis that ageing females with partly depleted lipid reserves produce biologically relevant amounts of fatty acids de novo. Females with varying oviposition history (0-48 h) prior to feeding 20% 13C-labelled glucose solution showed 13C-incorporation rates of (mean ± SEM) 30±2%, 50±2%, 49±3%, and 21±2% in palmitic, stearic, oleic, and linoleic acid, respectively. The absolute amounts of fatty acids synthesised de novo across treatments corresponded to 28±3 egg lipid equivalents. Females incorporated de novo synthesised fatty acids into their eggs, and glucose-fed females laid more eggs than water-fed control females. The number of eggs laid prior to glucose feeding did not correlate with the degree of lipogenesis, b...