Is plasticity of lipid synthesis due to methylation as an epigenetic marker ?

Parasitoids are organisms that develop using a host that they kill during or at the end of their development. A few years ago, parasitoid insects were thought to have lost the ability to synthesize their own lipids due to their inability to accumulate storage fat. In 2010, Visser et al. determined that loss of lipid synthesis in parasitoids was correlated with parasitism in insects. However, they also noted that some species were once again able to synthesize lipids. Visser et al. collected populations of Leptopilina heterotoma, a parasitoid wasp, in Asia and Europe. These populations showed variability in lipid synthesis despite genetic homogeneity. They hypothetized that this could be explained by a plasticity of lipid synthesis. Another experiment was then developed showing that there is a plasticity for lipid synthesis and that it is due to environmental conditions during development in the host: if the host has a lot of fat, the parasitoid does not activate its lipid synthesis and vice versa. Currently, it is assumed that the phenotypic plasticity observed in these insects is due to epigenetic marks and, more specifically, DNA methylation. Thus, the environmental conditions during the larval development of the parasitoid would lead to a modification of the methylation pattern of the DNA. Methylation of DNA makes the methylated part generally less expressed during transcription. Variations in the methylation pattern can then be expected depending on the environmental conditions of the parasitoid during its development in the host. To verify that DNA methylation was responsible for the plasticity of lipid synthesis, an experiment is set up with a split-brood design. The individuals generated will then have to be cut in half to be able to study the lipids and DNA/RNA of the same individual. Various DNA/RNA extractions will be performed to determine the most appropriate way to extract these molecules to perform RNA analysis to determine which genes have different expression depending on the environmental conditions and to do a pyrosequencing on DNA to check the methylation patterns of the targeted genes.