Figure 3. Characterization of tegumented, viral HSV1 capsids.

The MAP binding (Fig. 2; left 4 data sets) to the three viral capsid types treated with 0.1, 0.5 or 1 M KCl (panels A, B and C, respectively) and their inner (middle 8 data sets) and outer tegument (right 8 data sets) organization (Figs. 6,7,8) have been analyzed by immunoblot (IB), quantitative mass spectrometry (MS), and quantitative immunoelectron microscopy (IEM). While IB and MS indicate the amount of different tegument proteins on the capsids, the IEM determines to what extent such tegument proteins were accessible on the capsid surfaces to antibodies or host factors. Please note that nuclear capsids did not bind to MAPs and contained very little tegument (c.f. Figs. 2, 6, 7, 8; data not shown in this figure). For further comparative analysis, we normalized the results of the IB, MS and IEM for the viral capsids such that the amount of a given MAP or a tegument protein on the capsids with the highest amount was set to 100%, and recalculated accordingly for the other capsid types (% of highest). These results are also listed in supplementary Table S1. Please note that in contrast to MS and IEM, the IB data were not quantitative. Instead, we only estimated the amount of the respective proteins based on the band intensities into 4 classes: absent (0%), minor (33%), major (66%) or highest (100%) amounts.