Improving the Accuracy and Scope of Quantitative FRAP Analysis

New mathematical models are presented for analysis of fluorescence recovery after photobleaching (FRAP) data to account for the conical geometry of photobleaching, for spatial variations in binding of fluorescent molecules, and for directed transport of fluorescent molecules. A fast computational method for calculation of fluorescence recovery with this conical geometry is presented, and is shown to be applicable in calculations with spatial variations. Some of the new models are applied to experimental data from a previously published paper (Biophys. J. 95:3048) and are found to reinforce the existing conclusions, and furthermore to suggest that the protein γ-tubulin is likely to be uncomplexed in the cytoplasm.