Fig. 1. Tau activates NF-κB pathway in microglia.

a Volcano plot of significant DEGs between full-length wild-type tau fibril-treated and vehicle-treated primary mouse microglia. Colored points represent FDR < 0.05 (−log (FDR) ≥ 1.3, dashed line), log₂FC > 0 upregulated genes (red) and log₂FC < 0 downregulated genes (blue). Selected NF-κB pathway associated genes and DAM signature genes are highlighted. FC fold change. b Selected IPA canonical pathways identified for significant DEGs of tau-stimulated microglia. Canonical pathways are grouped by indicated categories. c, d Primary microglia infected with NF-κB reporter (Lenti-κB-dEGFP) virus were incubated with K18/PL fibrils (2.5 ug/ml), full-length wild-type (FL-WT) tau fibrils (2 ug/ml), and LPS (50 ng/ml) for 24 h. c Representative fluorescence high-content images of EGFP (green) and microglial marker Iba1 (red); d Quantification of EGFP intensity. Scale bar, 50 μm. Values are mean ± SD, relative to vehicle control. Total N = 18(ctrl), 19(K18/PL), 22(FL-WT) and 19(LPS) wells from three independent experiments. P-value was calculated using multilevel mixed-effect model with experiment as hierarchical level, ***p < 0.001. Source data are provided as a Source data file. e Volcano plot of significant DEGs between isolated microglia from 11-month-old PS19 mice and non-transgenic controls. Selected NF-κB pathway associated genes and DAM signature genes are highlighted. f Selected IPA canonical pathways identified for significant DEGs in PS19 microglia. Canonical pathways are grouped by indicated categories. g, h Selected IPA predicted upstream regulators for DEGs of tau-stimulated microglia (g) and PS19 microglia (h). IKBKB (distinguished in red) is among the top upstream regulators. i, j The network of DEGs regulated by IKBKB in tau-stimulated microglia (i) and PS19 microglia (j). Locations, gene expression levels and predicted relationships with IKBKB are illustrated as indicated labels. Shades of red and green represent log₂FC of selected DEGs. Genes highlighted in blue in a and e are selected DEGs upregulated in both tau-stimulated microglia and PS19 microglia. P-values of b, f, g, h were calculated using right-tailed Fisher’s exact test with threshold of significant enrichment as p-value ≤ 0.05 (indicated by a dotted line of −log (p-value) = 1.3).