Journal: eLife
Article Title: Genome-wide CRISPRi screening identifies OCIAD1 as a prohibitin client and regulatory determinant of mitochondrial Complex III assembly in human cells
doi: 10.7554/eLife.67624
Figure Lengend Snippet: ( A ) Schematic overview of the genome-wide CRISPRi screen. K562 dCas9 cells stably expressing dCas9-KRAB were infected with a pooled genome-scale sgRNA library. After growth in galactose, cells were subjected to four pulses of antimycin A or vehicle treatment followed by a 48 hr recovery period. After the last antimycin A pulse, genomic DNA from each condition was isolated and sgRNA abundance was quantified by deep sequencing. ( B ) Volcano plot showing the statistical significance (y axis) versus phenotype scores (ρ, x axis) of control non-targeting and genome-wide targeting sgRNAs. Knockdown of Complex III structural proteins and assembly factors sensitized cells to antimycin A. Genes were considered a hit if they scored above a threshold of ρ z-score x−log 10 p-value of 7 (dashed line). ( C ) CRISPRi knockdown of ovarian carcinoma immunoreactive antigen domain-containing protein 1 (OCIAD1) expression. Western blot showing the expression level of OCIAD1 in K562 dCas9-KRAB cells stably expressing either a control non-targeting sgRNA or two different sgRNAs against OCIAD1. CRISPRi-based silencing reduced OCIAD1 protein expression by ~90%. ( D ) Validation of the OCIAD1 phenotype. K562 dCas9 cells were mixed with an equal number of K562 dCas9-KRAB BFP + cells stably expressing a non-targeting sgRNA (brown bars) or an sgRNA against OCIAD1 (light blue bars). Cell mixtures were then treated with the drug or a vehicle for 24 hr. The percentage of BFP + cells in the cell mixtures was measured by flow cytometry before and 24 hr after treatment. OCIAD1 silencing selectively sensitized cells to antimycin treatment.
Article Snippet: A control cell line was generated by infecting U2OS cells stably expressing a non-targeting sgRNA (above) with the lentivirus vector pLKO.1-blast-Scramble (Addgene, cat# 26701) expressing a non-targeting shRNA sequence and selected with 15 μg/mL blasticidin for 7 days.
Techniques: Genome Wide, Stable Transfection, Expressing, Infection, Isolation, Sequencing, Control, Knockdown, Western Blot, Biomarker Discovery, Flow Cytometry