eLife Assessment
Giamundo et al. present fundamental data with new insights into the role of Ezrin, a major membrane-actin linker that assembles signaling complexes, in the spatial regulation of EGF signaling mediators. The use of multiple state-of-the-art microscopy techniques, multiple cell lines and inhibitors, together with in vivo models convincingly supports the majority of their conclusions. The findings are helpful for understanding EGF/mTOR signal transduction and support a critical role for the scaffolding protein Ezrin in the upstream regulation of EGFR/AKT activity, TSC subcellular localization and mTORC1 signaling. These findings contribute substantially to understanding how endo-lysosomal signaling are regulated, alterations which are implicated in many human diseases.