The immunofluorescence assays and confocal microscopy were conducted as described previously . 293T cells grown on glass-bottom dish (MatTek) in complete medium were co-transfected with fluorescently tagged expression vectors for DHX29 (DsRed2) and low concentration of MDA5 (GFP) for 12–16 hr. Cells were either left untreated or treated with LMW Poly(I:C) or EMCV for 5 h. Cells were live-recorded at every 50 min or fixed in 4% paraformaldehyde solution in PBS at room temperature for 15 min. The nucleus was then labeled with DAPI for 5 min in the dark and then followed by three washes in PBS. Samples were then visualized using Nikon Eclipse Ti-E microscope. All acquired images were analyzed and the correlation coefficient (r) of pixel intensity values was extracted by using the Nikon NIS-Elements AR package or the ImageJ (NIH) software.