▲ CRITICAL STEP Check under the microscope to ensure dissociation to single cells. 58Spin down the cells at 200g for 5 min at room temperature.59Aspirate the medium, and resuspend it in 200 μl of FACS medium.60Filter the cells into the cell strainer tube through its mesh cap. Place the cells on ice until sorting.61Sort single cells into the 96-well plates prepared from Step 55. If sgRNA is cloned into pSpCas9(BB)-2A-GFP, fluorescence may be used to enrich for transfected cells. After sorting, examine the plate under a microscope and determine the presence of a single cell in most of the wells on the plate.
