Fig. 1

Ddx56 knockout affects ribosome assembly and leads to cell lethality. a The generation of doxycycline (Dox)-inducible Cas9 expression in A17-2loxP mESCs (iCas9 mESCs). b The strategy of generating doxycycline-inducible Ddx56 knockout ESC line (Ddx56 iKO mESCs). Bar, 600 μm. c Ddx56 iKO mESCs were cultured with doxycycline (1 μg/mL) (+Dox) or without doxycycline (−Dox) for 3 days. GFP iKO mESCs served as a negative control. Cdk1 iKO mESCs served as a positive control. Cells were visualized by phase-contrast microscopy. × 4, objective. d Cells were stained with propidium iodide (PI) and then observed under a fluorescence microscope. e Cells were stained with PI and Annexin V-FITC, subjected to FACS analysis. f Cells were cultured with (+Dox) or without (−Dox) doxycycline for 2 days and then subjected to ribosome profiling