As a next step in investigating the role of lipids in DENV induced membrane expansion we used high-resolution mass spectrometry to profile the lipid composition of DENV infected mosquito cells. We observed a very distinct segregation in the lipid composition between DENV infected and uninfected cells. Specific lipid changes that occurred upon virus binding and entry alone were also identified. In DENV infected cells, there was a selective enrichment of lipids that have characteristic functions in influencing membrane structure as well as those that have potent signaling functions. Among these lipids were bioactive sphingolipids such as sphingomyelin and ceramide, lysophospholipids and several intermediates such as mono-and diacylglycerol and phosphatidic acid. The phospholipids that were enriched in DENV infected cells were primarily unsaturated. There was also evidence for the up regulation of de novo phospholipid and sphingolipid biosynthesis as well as triacylglyceride metabolism ( Figure 8 ). Furthermore, we identified a unique lipid environment that supported cell survival but did not support DENV replication. This environment was created by the addition of C75, an inhibitor of fatty acid synthase, the rate-limiting step in phospholipid biosynthesis.