Representative Coomassie-stained SDS-PAGE gel showing the isolation of SDS insoluble aggregates from mouse brain lysates. TH = total homogenate, SUP = supernatant, W1 = SDS-soluble fraction, Pellet = formic-acid soluble fraction (see Figure EV4A). Quantification of the yield of SDS-insoluble aggregates from young and old brain lysates was based on densitometry analysis of Coomassie-stained gel bands obtained from different animals, n=5 per age group (Figure EV4B); ** p < 0.01, unpaired t-test. In boxplots, the horizontal line represents the median, the bottom and top of the box the 25th and 75th percentile, respectively, and the whiskers extend 1.5 folds the interquartile range. 