Extended Data Fig. 5. MPRA of mutated sequences.

MPRA experiments were performed in Arabidopsis protoplasts using synthetically mutated sequences inserted only in the downstream position. Both p35S- and pTRP1-based libraries were used. The libraries contained 30,000 fragments: 12,000 from the initial pool and an additional 18,000 fragments, each being a variant of one of the original fragments. (a) Comparison between each pair from the three replicates, displaying results with the p35S-based library at the top and the pTRP1-based library at the bottom. Pearson’s correlation coefficients (r) and numbers of compared fragments (n) are indicated on each graph. (b) Log₂ expression ratio between mutated fragments and their original fragment. Mutations encompass: addition of a GATC motif, removal of a GATC motif, 10 bp deletions, and 1 bp changes, which include both deletions and nucleotide substitutions. Color represents the library type, either p35S- or pTRP1-based; numbers below the x-axis indicate the number of fragments in each category. Error bars depict the mean with ±1 standard deviation.