S1D), in accord with the increasing appreciation of these factors in AD development [24] (see discussion). Moreover, several proteins encoded by PI3K-AKT target genes are also enriched in the CM from PFF-treated PAs (Fig. 4I), further corroborating our transcriptome analysis. Surprisingly, mass spectrometry also identified a large number of proteasome subunits in the medium in response to tau PFF treatment (Fig. 4H). Immunoblotting with available proteasome antibodies confirmed the presence of the  α7 subunit in the CM (fig. S1E). This evidence concerns the gene MAPT and Alzheimer disease.