Cells and organisms are complex machines driven by a set of dynamic biological events tightly orchestrated in space and time. The comprehensive molecular understanding of their inner workings requires acute molecular tools to observe and modulate the key triggers and cell signaling events. To study the molecular mechanisms that govern cells and organisms over different scales in time and space, our team combines chemistry with protein engineering and genetic tools to develop novel approaches for the quantitative imaging and acute modulation of individual small molecules, proteins, organelles or cells. These tools can enable to address questions ranging from fundamental mechanisms to the causes of disease and the development of novel therapeutics.