Figure 6

Insulin-induced glucose uptake and glycogen synthesis were both decreased by an expression of E2 protein. After being transfected with FLAG-CMV2 or FLAG-E2 for 24 hours and a serum-free incubation 16 hours, cells were subjected to insulin stimulation for 13 minutes and then glucose uptake analysis with 2-deoxy-d-[1,2-³ H] glucose. [³ H] glucose uptake levels were quantified with liquid scintillation counter and presented as a percentage to that of control (A). For glycogen synthesis analysis, the insulin stimulation was carried out for 9 hours before cells were subjected to glycogen assay kit (B). These results clearly indicated that E2 protein can inhibit insulin-induced cellular glucose uptake and glycogen synthesis. The error bars represented standard deviation from triplicate experiments. * indicates p<0.05 and ** indicates p<0.01.