MIET imaging of cells

The PIs of project A14 (Chizhik, Janshoff) teamed up with colleagues from projects A12 (Köster) and A13 (Rehfeldt, Schmidt) to study the collective dynamics and self-organization of the cleft between cells and their substrate using metal induced energy transfer (MIET) imaging, which was developed in the first funding period. The method allows for dual-color axial nanometric localization and can be combined with Förster resonance energy transfer (FRET) to resolve structural details of cellular adhesion complexes on the molecular level. An example is the three-dimensional architecture of stress fibers anchoring at focal adhesions in human mesenchymal stem cells (A13) (Chizhik et al., Mol. Biol. Cell (2018) 29:773-880). Similar methods were also applied to unravel the collective dynamics of the epithelial-to-mesenchymal transition (A14) and to generate new insights into the adhesion of blood platelets (A12).



MIET microscopy reveals cell-substrate dynamics. MIET imaging relies on the distance dependence of fluorescence lifetime (left) providing unprecedented axial resolution of the cell-subtrate cleft (center). Right: Sketch of an adhesive cell, including actin stress fibers (red) and focal adhesions (green). Insets: dual-color MIET imaging of vinculin (left) and actin (right) of cells fixed 6 hours after adhesion.