ZUP1 and infection: From these observations, it thus appears that the differences in symptoms severity among the various mutants do not correlate with the DUB activity per se, as the I847A and I847D mutants caused symptoms similar to WT infection, despite having drastically different levels of DUB enzymatic activity, whereas mutants G865A and D843A caused extremely dissimilar symptoms, despite having comparable levels of DUB enzymatic activity (Table 2 and Fig 4).