GFP fluorescence can be modulated in mammalian cells by binding to single-chain antibodies (nanobodies), selected to make GFP brighter or dimmer; these changes are explained by the crystal structures of the GFP-nanobody complexes. The applications of such nanobodies to monitor protein expression and subcellular localization in real time are explored.
- Axel Kirchhofer
- Jonas Helma
- Ulrich Rothbauer
