| Here , we investigated the consequences of pharmacological inhibition of PI3K on Toll IL 1 receptor domain containing adapter inducing IFN beta ( TRIF ) dependent signaling , which induces IFN beta gene expression downstream of TLR 3 and TLR 4 . ^^^ Experiments carried out in HEK 293T cells stably expressing TLR 3 or TLR 4 confirmed that inhibition of PI3K activity enhances NF kappaB dependent promoters as well as IFN beta promoter activities without interfering with transcription at the positive regulatory domain 3 1 . ^^^ We conclude that inhibition of PI3K activity enhances TRIF dependent NF kappaB activity , and thereby increases IFN beta synthesis elicited by TLR 3 or TLR 4 ligands . . ^^^ |