Reversion of C1 in the C1-overexpressing strain cRluc5b2 includes reversion of the C3 level. A, Different amounts of proteins from a crude extract (90, 60, and 30 μg per lane) labeled as 3x, 2x, and 1x, respectively, of cRluc5b2 cells that had been transformed in some cases with the C1ox vector (cRluc5b2::C1ox) were separated by 9% SDS-PAGE. They were used for immunodetection with anti-C1 and anti-C3 antibodies, respectively. cRluc5b2::C1ox cells were grown and harvested at different time points after transformation, as indicated. B, Quantification of the expression levels of C1 and C3 via ImageMaster 2D Elite version 4.01 (GE Healthcare) according to “Materials and Methods” in C1ox strains in percentage in comparison with the appropriate control strain (n = 2). C, Measurements of cRLUC activities in the cRluc5b2::C1ox strain at different time points after transformation in relative light units (RLU; n = 3). Error bars represent the se of technical replicates. Cells were grown at 23°C and used at LD2 to measure the cRLUC activities.