The evolution, evolvability, and engineering of gene regulatory DNA [GPRA]

In order to generate data produce a generalizable sequence-to-expression model, we randomly sampled ~21 million 80 bp sequences and tested their activity as promoters (in yeast) by measuring expression level by FACS (sorting into 18 bins). Here, all libraries tested have the following sequences flanking the random 80 bp oligo: the pTpA distal region was (pT) GCTAGCAGGAATGATGCAAAAGGTTCCCGATTCGAACTGCATTTTTTTCACATC and proximal region (pA) was GGTTACGGCTGTTTCTTAATTAAAAAAAGATAGAAAACATTAGGAGTGTAACACAAGACTTTCGGATCCTGAGCAGGCAAGATAAACGA (up to the theoretical TSS). 80 Ns were inserted in between proximal and distal regions. Here, both experiments represent yeast grown in SD-Ura (Sunrise Sciences), and the designed-sequence library used a strain of S288C with Ura3 deleted, while the large-scale random promoter library used strain Y8205 (Boone Lab).