Extended Data Fig. 4: Screen for factors modulating number of resistant colonies upon BRAF^V600E inhibition.

a, We performed a pooled CRISPR screen to detect modulators of the number of drug-resistant cells that grow in the presence of the BRAF^V600E inhibitor vemurafenib. After transducing a library of single guide RNAs and expanding the population, we exposed the cells to the BRAF^V600E inhibitor vemurafenib (1 µM) for 3 weeks, after which we sequenced the single guide RNAs in the surviving population. Changes in the frequency of detection of a given single guide RNA indicates that its target may affect the ability of a cell to survive and proliferate upon BRAF^V600E inhibition. b, After transfecting a population of melanoma cells, we exposed them to vemurafenib (BRAF^V600E inhibitor, 1 μM) for 3 weeks to grow resistant colonies. We then sequenced the DNA to quantify the single guide RNA representation of each target in the resulting population, using the same libraries as in Fig. 1. As before, we ranked the targets into tiers based on the percent of single guide RNAs that exhibited at least a two-fold change in representation throughout the screen (Tier 1, ≥ 75%; Tier 2, ≥ 66%; Tier 3, ≥ 50%; Tier 4, < 50%), thus reflecting the degree of confidence we have in the hit (High confidence hits: Tiers 1 and 2; Low confidence hits: Tiers 3 and 4). In this screen, we identified 24 high confidence factors. For a more detailed description, see the Methods section.