Transcription factors with increased activity in AUD plausibly impact the accessibility of related DNA motifs on their target genes44. We found 99 transcription factor motifs with significantly different enrichment in those with AUD (FDR < 0.2) using chromVAR45. Notably, 15 of the top 20 enriched motifs are annotated by JASPAR46 as bZIP transcription factors (Supplementary Data 16), including JUND (FDR = 0.16), the only gene identified in both the gene regulatory network and motif enrichment analyses as having increased activity in astrocytes in AUD. An ANOVA using pseudobulk-level motif enrichment (see “Methods”) confirmed a significant difference in JUND enrichment in individuals with AUD (p = 0.0028, Fig. 4a). Astrocytes with high JUND motif enrichment were largely in regions with high complement component 3 (C3) expression, a marker of reactive astrogliosis (Fig. 4b)47. C3 expression was significantly higher in individuals with AUD (1.65 fold, FDR = 0.0007; Fig. 4c).
