Ratio of EGFP protein levels between cells transfected with the siRNAs specific for EGFP, and negative control cells, transfected with a non-specific siRNAs, measured 60 hours after transfection. Error-bars represent the standard-error from three biological replicates for each point. The x-axis reports the different quantities of siRNA oligomers tested. Protein levels were measured using FACS analysis quantifying EGFP protein fluorescence. The error-bars have the length of one standard error.