Extended Data Figure 1. Experimental Metrics Demonstrating Robustness and Consistency of MPRA Assay Across Cell Lines for Library 1.

A. Sequence count distributions for 5ʼUTRs (left) and 3ʼUTRs (right) across all individual libraries, before (top) and after normalization (bottom) for different cell lines. Each boxplot represents data for a single library.

B. Pairwise Pearson correlation heatmaps showing reproducibility of sequence activity between replicates and across the cell lines for 5ʼUTRs (left) and 3ʼUTRs (right). Color scale saturation: Pearson correlation value.

C. Scatterplots comparing sequence activity measurements between replicates for each cell line. Pearson correlation coefficients (r) are shown on the plots for 5ʼUTRs (green) and 3ʼUTRs (purple).

D. PCA of 5ʼUTR (left) and 3ʼUTR (right) libraries, points are colored by the cell line. The markers are numbered according to the sorting bin numbers and shaped according to replicates.