Fig. 2.

Validation of DENV-human protein interactions in the split-luciferase assay. DENV and human proteins were expressed in wheat germ extracts as fusions to the N- and C-terminal fragments of firefly luciferase, respectively. In vitro translated DENV and human proteins were mixed in PBS supplemented with 1% BSA and protease inhibitors (Roche) and incubated overnight at 4 °C. As negative controls, each viral protein was tested against the empty C-terminal luciferase vector and each human protein was tested against the empty N-terminal luciferase vector. Binding reactions were set up in duplicate and luciferase activity was measured twice for each reaction. Graph shows the average of the four luciferase readings normalized to the luciferase activity of the DENV protein with the empty C-terminal luciferase negative control, which was set at 100 relative light units (RLU). Error bars indicate the S.E. Asterisks indicate pairs of interacting proteins that yielded luciferase activity that was significantly greater than both negative controls (student's unpaired t test, p value <0.02).