Fig. 1

Synthetic lethal CRISPR screening to identify potential cholesterol regulators in HepG2 cells. A Immunoblot analysis of HMGCR in HepG2 cells undergoing CRISPR-mediated gene knockout with two independent sgRNAs (numbered as _1 and _2). Vector without specific sgRNA insert serves as a control. GAPDH serves as a loading control. B Immunoblot analysis of LDLR in HepG2 cells that have undergone CRISPR-mediated gene knockout with two independent sgRNAs. C The cell growth analysis of HepG2 cells after introducing indicated sgRNAs via lentiviral infection for 7 days. Cells were counted with a hemacytometer. Mean ± SD with n = 3. Ordinary one-way ANOVA with Tukey’s test, **p < 0.01, ***p < 0.001. D The relative cell viability was determined by CCK-8 assay for HepG2 cells expressing indicated sgRNAs and treated with indicated doses of lovastatin. Mean ± SD with n = 6. Ordinary one-way ANOVA with Dunnett’s test, *p < 0.05, **p < 0.01, ***p < 0.001. E The workflow of genome-scale synthetic lethal CRISPR screens (Screen 1) to identify negative GIs with HMGCR using its inhibitor lovastatin in HepG2 cells. F The scatter plot showing the β score of each gene and the correlation of both CRISPR screens (vehicle and lovastatin) in HepG2 cells. The genes in blue box are preferential targets as the synthetic lethal or negative GI hits. G The rank-ordered list of each gene in the CRISPR screens according to the strength of synthetic lethality measured by differential β scores between lovastatin and vehicle conditions. The top interesting gene hits are highlighted. H The top selected functional terms enriched among synthetic lethal hits of the CRISPR screens (Screen 1) as determined by the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis