Normalization reads (plasmid DNA) of plasmid mix with TRIP promoter constructs
For ADAMTS1, ARHGEF9, BRINP1, MED30, PGK, TMEM106B and ZNF300  promoters, barcoded TRIP plasmid library was transformed into DH5-alpha E. coli and plated; 100 colonies were picked, pooled, and expanded to produce plasmid mini-libraries with 100 different barcodes each. Next, the plasmid mini-libraries of the 7 promoters were mixed in equal porportions and transfected into K562 cells by the same nucleofection method as used for SuRE (van Arensbergen et al., 2016). Two days after transfection, barcodes were counted in cDNA by PCR amplification and Illumina sequencing, similar to TRIP.