FIGURE 2.

FRET has little impact on FIR. (Left) Unscaled best-fit linear regressions lines of data points for eCFP and eYFP emissions from cells expressing eCFP-m and eYFP-m at cDNA ratios of 2:1 and 1:2 in the absence of FRET (blue) and with hypothetical FRET of 30% between these fluorophores (red; 2:1′ and 1:2′). Also shown are the FIR values k₁ and k₂, and k′₁ and k′₂ in the absence and presence of FRET, respectively. (Right) Results from panel A scaled using the constant C (blue) and C′ (red). The green lines represent the maximum possible error introduced by FRET for the 2:1 and 1:2 regression lines. Black dashed lines indicated predicted eCFP-m and eYFP-m membrane levels at the indicated expression ratios.