A method to transform rice protoplasts in a 96-well plate. Renilla luciferase activities in rice protoplasts transformed with pYFP-RLuc, the vector expressing full-length Renilla luciferase (Fujikawa and Kato ) were measured in a 96-well plate. Protoplasts (5,000 cells) isolated from rice leaves were placed in each well, except in wells of column 1 that served as sample-free controls. The protoplasts were then transformed with the vector. The luminescence in each well was measured by a microplate reader 16 h after the transformation. The relative luminescence units (RLUs) in each well are expressed as a white-to-red heatmap. The calibration bar is shown on the right. Notice transformation bias is not observed in the plate. n: sample number.