H2020 ERC Catch

It has become evident in the previous 2 decades that living matter is not only controlled by chemical signals and cues but by mechanical stress as well. The effect of mechanical stress on cell development, differentiation and polarization has been studied in mammalian cell for years but knowledge on the response of plant cells to mechanical stress is lacking. Since plant cells contain a strong, rigid cell wall, which mammalian cell lack, the elastic modulus of plant cells is multiple orders of magnitudes larger than that of mammalian cells, >10 MPa for Arabidopsis hypocotyls and 12 kPa for mice bone muscle. It is expected that plant cell responses to mechanical cues is fundamentally different than the response of mammalian cells to these cues. Since the cell wall is the main transducer of mechanical forces from both outside and within plants tools to study the mechanical state of cell walls are essential. BODIPY dyes, which behave as molecular rotors, have been used to map viscosity and local degrees of freedom in mammalian cells and different structures of plant cells. This allows for indirect visualization of local mechanical stress using FLIM (Fluorescence Lifetime Imaging Microscopy). Targeting the cell wall however remains challenging and currently most dyes targeting the cell wall are antibody-dye conjugates or are derived from textile dyes and their fluorescent core partakes in targeting through hydrophobic interactions. Small molecular motifs that specifically bind to cell walls are highly desirable since it would allow for the synthesis of a wide variety of fluorescent reporters targeting the cell wall while currently only a limited number of reporters exist. These molecular motifs currently are not known yet, by using a combinatorial approach where we link BODIPY dyes with simple structures suspected of targeting the cell wall we hope to identify cell wall targeting motifs. This would enable us to further study the effect of mechanical stress on plant cell development, differentiation and growth, share these new dyes with the community and create a toolbox of molecular motifs that can be used to create new fluorescent reporters targeting the cell wall with unprecedented freedom.