HEK293T cell transfection

One microgram of pX330-Satb2 was mixed with 1 μg of pCAG-EGxxFP-Satb2 and then introduced into HEK293T cells with polyethylenimine. To label transfected cells, 500 ng of pCAG-mCherry plasmid was used. The EGFP and mCherry fluorescence was observed under a fluorescence microscope 48 hours after transfection. To quantify the percentage of mCherry-positive transfected cells that became EGFP-positive, epifluorescence microscopic images were analyzed by ImageJ software (National Institutes of Health). Cells which had EGFP signal intensity stronger than the maximum signal intensity of the background in negative control samples were defined as EGFP-positive cells, and the number of EGFP-positive cells was counted. Statistical significance was determined using one-way analysis of variance.