Fig. 6.

STEM imaging reveals that packing of Tau in assembly conditions is severely altered by GFP tags. (a) Mass per length histograms (MPL) of fibrils aggregated for 24 h at 37 °C, with fitted peak values (in kDa/nm) listed for each protein. Examples of STEM images are shown for Tau^FL-wt(b), GFP-Tau^FL-wt(c), Tau^RDΔK(d); Tau^RDΔK-GFP fibrils (long) (e) and Tau^RDΔK-GFP fibrils (short) (f). MPL measurements were calibrated with tobacco mosaic virus (TMV, shown in the bottom histogram in a and in image g). The estimated molecules per nm are presented in Table 1. Note that Tau^RDΔK-GFP fibrils have been observed mostly as short and stubby fibrils, but that the long fibrils show a packing, less dense than the short fibrils