Journal: bioRxiv
Article Title: CRISPR Screens Reveal Epstein-Barr Virus-activated JunB as a Key Lymphoblastoid B cell Dependency Factor that Represses Cyclin Dependent Kinase Inhibitor P18INK4c
doi: 10.64898/2026.03.31.715635
Figure Lengend Snippet: (A) Validation of JunB CRISPR-Cas9 knockout in MUTU I and GM15892 cells. Immunoblot was performed on WCL from Cas9+ MUTU I and GM15892 cells transduced with control or JunB sgRNA seven days post-selection using indicated antibodies. (B) Mean ± SD live cell numbers of Cas9+ MUTU I or GM11830 cells expressing control or JunB targeting single guide RNAs (sgRNA) from n=3 replicates. Cells transduced with lentiviruses expressing the indicated sgRNAs were puromycin selected. Cell numbers two days following puromycin selection (defined as day 0 of the graph) were set to 1. Live cell numbers were quantitated by CellTiter-Glo assay (C) Investigation of impact of JunB on other Jun AP-1 transcription factors. Immunoblot analysis of WCL from Cas9+ GM12878 cells transduced with control or JunB sgRNAs, ten days post selection, with indicated antibodies. Densitometry ratios of JunB and JunD to β-Actin is shown. (D) Investigation of combinatorial impact of JunB and JunD on LCL growth. (Left) Mean ± SD live cell numbers of Cas9+ GM12878 cells expressing control, JunD, JunB, or JunB+JunD targeting single guide RNAs (sgRNA) from n=3 replicates. Cells transduced with lentiviruses expressing control or JunD sgRNA were Zeocin selected two days post transduction. After one week, cells were then transduced with a separate control or JunB sgRNA. Cell numbers two days following puromycin selection (defined as day 0 of the graph) were set to 1. Live cell numbers were quantitated by CellTiter-Glo assay. (Right) Immunoblot validation of JunB and JunD knockouts. WCL of GM12878 cells transduced with both zeocin and puromycin sgRNAs was extracted two days following puromycin selection and immunoblot was performed using indicate antibodies. (E) PI cell cycle stainin of GM12878 cells transduced with JunB sgRNA. Representative FACS cell cycle plots from n=3 replicates of GM12878 cells analyzed ten days post selection. P-values were determined by one-sided Fisher’s exact test. * p<0.05, **p<0.005, ***p<0.0005
Article Snippet: Antibodies against the following proteins were used in this study: JunB (Cell Signaling Technology, #3753), c-Jun (Cell Signaling Biotechnology, #9165), JunD (Cell Signaling Biotechnology, #5000), β-Actin (Biolegend, #664802), LMP1 (Abcam, ab78113), LMP2A (Abcam, ab59028), EBNA2 PE2 (a gift from Fred Wang), DDX1 (Bethyl, A300-521A-M), Myc (Santa Cruz Biotechnology, SC-40), p100/p52 (EMD Millipore, 05-361), TRAF1 (Cell Signaling Biotechnology, #4715S), HA tag antibody (Cell Signaling Technology, # 3724), BIM (Cell Signaling Biotechnology, #2933), CCND2 (Proteintech, 10934-1-AP), EBNA1 (a gift from Jaap Middeldorp), and EBNA3C A10 (hybridoma from Martin Rowe’s group[ ]).
Techniques: Biomarker Discovery, CRISPR, Knock-Out, Western Blot, Transduction, Control, Selection, Expressing, Glo Assay