Fluorescence imaging has become an indispensable tool in cell and molecular biology. Genetically encoded fluorophores have revolutionized fluorescence microscopy, giving experimenters exquisite control over the localization and specificity of tagged constructs. However, these systems present certain drawbacks and as such, alternative hybrid systems based on the interaction between a small molecule fluorophore and a protein have been developed. A way to avoid unspecific background in cells and achieve high imaging contrast is to use fluorescent probes that display no fluorescence until labeling occurs. Such probes are often called fluorogenic probes to highlight their ability to generate fluorescence upon reaction/interaction with their target. A new fluorogenic hybrid system called the Fluorescence-activation and Absorption Shifting Tag (FAST) was developed, which consists of a small protein tag that reversibly and dynamically binds a small molecule chromophore, activating its fluorescence. Hybrid chemical-genetic systems such as FAST represent unique opportunities to extend the utility of the system as the protein and fluorogen present two opportunities for engineering. I will present work on improvements to the system and the development of biosensors based on such hybrid systems.

1.Plamont, M.-A. et al. Small fluorescence-activating and absorption-shifting tag for tunable protein imaging in vivo. Proc. Natl. Acad. Sci. U. S. A 113, 497–502 (2016).
2.Tebo, A. G., Pimenta, F. M., Zhang, Y. & Gautier, A. Improved Chemical-Genetic Fluorescent Markers for Live Cell Microscopy. Biochemistry 57, 5648–5653 (2018).
3.Tebo, A. G. et al. Circularly Permuted Fluorogenic Proteins for the Design of Modular Biosensors. ACS Chem. Biol. 13, 2392–2397 (2018).
Date: 31 January 2019, 11:00 (Thursday, 3rd week, Hilary 2019)
Venue: Wellcome Trust Centre for Human Genetics, Headington OX3 7BN
Venue Details: Meeting room A
Speaker: Dr Alison G. Tebo (Department of Chemistry, École Normale Supérieure, Paris, France)
Organising department: Wellcome Trust Centre for Human Genetics
Organiser: Agata Krupa (Wellcome Centre for Human Genetics, University of Oxford)
Host: Dr Sergi Padilla Parra (University of Oxford)
Part of: Strubi seminars
Booking required?: Not required
Audience: Members of the University only
Editor: Agata Krupa