Comparison of PF8503 and homoharringtonine CRISPRi screens.

(A) Comparison of gene knockdowns that had significant effects on compound toxicity (Rho phenotype) in CRISPRi screens in the presence of homoharringtonin (HHT) or PF8503. Knockdowns with significant effects in the presence of HHT alone (HHT only, grey), PF8503 alone (PF8503 only, red), or in the presence of either compound (PF8503+HHT, blue) are shown. (B) Venn diagram of significant genes in the HHT and PF8503 CRISPRi screens. (C) Pathways enriched in the common and distinct collection of genes in the HHT and PF8503 CRISPRi screens. Gene count observed corresponds to the number of genes attributed to this pathway by STRING, as a percentage of the total number of genes attributed to a pathway (D). Phenotypes obtained in K562_dCas9-KRAB competition experiments (scrambled sgRNA as control), with cells treated with three different translation inhibitors: 20 nM HHT, 7.5 μM PF8503, or 7.5 μM PF846. Included are examples predicted to be part of translation quality control (ASCC2, ASCC3, HBS1L, NEMF), RNA transport (ALYREF) and ubiquitin-mediated proteolysis (UBR5). Experiments carried in biological triplicate, with mean and standard deviation shown.