Tracking Focal Adhesion Turnover: A Novel Reporter for FA-Phagy Flux

Focal adhesions (FAs) are critical multi-protein complexes regulating cell adhesion, migration, and survival, and their dysregulation contributes to cancer metastasis and vascular diseases. Despite extensive research on FA formation, little is known about FA turnover, particularly its regulation by autophagy. This study introduces a novel tandem fluorescence reporter capable of tracking the entire FA-phagy flux, from autophagosome formation to lysosomal degradation. The reporter, based on a red-green fluorescence system with a lysosome-specific cleavage site, integrates seamlessly into endogenous focal adhesion complexes, demonstrating sensitivity and specificity to autophagy stimuli. Validated in multiple cell lines, the tool revealed dynamic FA-phagy responses to starvation-induced autophagy and the involvement of autophagy regulators such as mTOR and ATG genes. This versatile reporter provides a powerful tool for investigating FA-phagy mechanisms, with significant implications for cancer biology and vascular research.