Protein-nucleic acid (DNA / RNA) interactions occur throughout the life of the plant cell, particularly to regulate cellular processes such as gene expression. Classical methods for analyzing such interactions are usually based on in vitro approaches, limiting the availability of spatio-temporal information.

Study in vivo interactions

The idea here was to produce in plants a fluorescent version of the protein of interest, by fusing it to a molecule conferring fluorescence called GFP and to mark the nucleic acids of the cell using a another fluorescent molecule, SYTOX Orange. If an interaction between the protein of interest and the nucleic acid takes place, a significant reduction in the lifespan of GFP is measured: this is the FRET effect, or energy transfer between a fluorescent donor molecule ( GFP) and an acceptor fluorescent molecule (SYTOX Orange) attached to the nucleic acids.

To acquire this information in real time despite the rapidity of this phenomenon, a particular microscope is needed: this is the Fluorescence Life Time Imaging Microscopy (FLIM) technology that allows this rapid acquisition

This new method represents a very promising tool to deepen our understanding of the biological mechanisms occuring in plants throughout their life cycle.