Authors: Gustavo Carrero and Michael J. Hendzel
Kinetic dynamics of nuclear proteins in living cells are often studied using two inverse-related fluorescence microscopy techniques: Fluorescence Recovery After Photobleaching (FRAP) and Photo Activated Fluorescence (PAF). Motivated by the inverse relationship between FRAP and PAF, we now report a method, Virtual PAF (VPAF), for obtaining the equivalent of PAF results directly from FRAP experiments. The method, based on simple image arithmetic, is validated mathematically using partial differential equations. The analysis provides a closed algebraic relationship between PAF and FRAP curves that is used to generate a set of VPAF data from FRAP data.
Keywords: Photobleaching, photoactivation, nuclear protein dynamics, live cell-imaging.