Figure 5. TFIIA is required by all promoters and is recruited by housekeeping cofactors to housekeeping promoters.

1. Western blot for an endogenously tagged TFIIA‐β‐3x‐FLAG‐AID cell line after addition of auxin at 1, 2 and 3 h indicating the TFIIA‐β C‐terminal cleaved product.
2. MA‐plot of PRO‐seq measurement 6 h after auxin addition to the TFIIA‐β‐AID cell line. Colored dots represent significant downregulation (fold change > 1.5 down; FDR < 0.05). Two biological replicates per condition. 10,125 protein‐coding genes are downregulated, with 73 genes not showing downregulation due to their overlap with noncoding RNA genes such as tRNA which are not affected by TFIIA‐β depletion.
3. PRO‐seq signal at all expressed promoters, represented according to their motif content in box plots. Boxes represent the upper and lower quartiles, with the middle band at the median. The whiskers represent the upper and lower 5^th percentiles across two biological replicates.
4. Overlap of TFIIA‐β‐3xFLAG immunoprecipitation mass spectrometry data with DNA affinity purification mass spectrometry of the three tested housekeeping promoter types. Three biological replicates per conditions with Limma P‐value < 0.05 and enrichment > 0.
5. Luciferase assay in which Gal4 DNA‐binding domain fusion proteins were recruited to 4xUAS sites upstream of a minimal housekeeping Rps12 promoter. Measurements are normalized to Renilla luciferase (transfection control) and GFP. * denotes proteins activating a housekeeping promoter with a log2FC > 1.5 and P‐value < 0.05, two‐tailed student's t‐test. Error bars represent standard deviation across four biological replicates.