TFAM and viral infectious disease: Interestingly, DPI treatment could reverse the depletion of both NRF1 and NRF2 due to virus infection (Figures 4(c), 4(d), and 4(f)), but it had no effect on the expression of TFAM (Figures 4(e) and 4(f)), which further confirmed that the virus infection stimulated TFAM signaling independent on either NRF1 or NRF2.