Robust calibration and quantification of FRET signals using multiplexed biosensor barcoding.

ABSTRACT: Förster resonance energy transfer (FRET) between fluorescent proteins (FPs) underpins many genetically encoded fluorescent biosensors for monitoring biochemical activities in live cells. However, the FRET ratio (acceptor-to-donor signal ratio), commonly used as a proxy for FRET efficiency, is highly sensitive to imaging parameters, complicating data interpretation. Using FP-based barcodes, we introduced calibration standards into subsets of cells for normalization of fluorescence signals. Theoretical analysis indicated the need for both high- and low-FRET standards for calibration under different excitation intensities. We validated this prediction using engineered "FRET-ON" and "FRET-OFF" standards, demonstrating that calibrated FRET ratios are independent of imaging conditions. Including

SUBMITTER: Wu JW 

PROVIDER: S-EPMC12595091 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature