Recently, exogenous PML-IV (but not PML-II) was reported to potentiate IFN-β expression in response to infection with vesicular stomatitis virus by sequestering at PML-NBs the peptidyl-prolyl cis/trans-isomerase (Pin1) that is needed for the degradation of the key activating TF, phosphoIRF3 (25). Here, IFNB1 is linked to infection.