While knockout mutants of ICP0 and ICP22 as well as the key viral host shut-off protein vhs still induced DoTT, this was substantially reduced upon infection with viruses deficient for ICP4 (ΔICP4 or TsK, a temperature-sensitive mutant of ICP4) or ICP27 (ΔICP27) (Fig. 1b). Here, PROS1 is linked to infection.