Fig. 1.

ProTα enables efficient cationic lipid-mediated protein delivery into HeLa-DsRed, BSR-tdTomato, and HEK293-RFP cell lines. EC₅₀ is defined as the protein concentration at which 50% of analyzed cells contain red fluorescence. In all cell lines tested, ProTα delivers Cre at low nM concentrations, ~10-fold more potent than (–30)GFP and ~100-fold more efficient than unmodified Cre. Values and error bars represent the mean and standard deviation of three independent biological replicates performed on different days. EC₅₀ values were determined by nonlinear fit to the Hill equation, and are followed by the standard errors of the fit. Source data are available in the Source Data file