What's past is prologue: FRAP keeps delivering 50 years later

Fluorescence recovery after photobleaching (FRAP) has emerged as one of the most widely utilized techniques to quantify binding and diffusion kinetics of biomolecules in biophysics. Since its inception in the mid-1970s, FRAP has been used to address an enormous array of questions including the characteristic features of lipid rafts, how cells regulate the viscosity of their cytoplasm, and the dynamics of biomolecules inside condensates formed by liquid-liquid phase separation. In this perspective, I briefly summarize the history of the field and discuss why FRAP has proven to be so incredibly versatile and popular. Next, I provide an overview of the extensive body of knowledge that has emerged on best practices for quantitative FRAP data analysis, followed by some recent examples of biological lessons learned using this powerful approach. Finally, I touch on new directions and opportunities for biophysicists to contribute to the continued development of this still-relevant research tool.

Automated summary

Fluorescence recovery after photobleaching (FRAP) is a widely used technique in biophysics for quantifying binding and diffusion kinetics of biomolecules. This article provides a brief history of FRAP, discusses its versatility and popularity, and summarizes the best practices for quantitative FRAP data analysis. It also presents recent examples of biological insights gained through the use of FRAP and explores new directions and opportunities for further development of this research tool.