Last October, about 120 researchers studying everything from biophysics to plant science met at Howard Hughes Medical Institute at Janelia Farm in Ashburn, Va., to discuss fluorescent proteins and biosensors. They'd been reading each other's papers for 15 years, but most had never met, and biophysicist Thomas Hughes of Montana State University remembers it as the most exciting meeting of his career. "I got the feeling from that conference that [biosensor development] really is going to be a field," he says. Indeed, techniques such as fluorescence resonance energy transfer (FRET) have become key tools in detecting real-time molecular interactions within living cells.
A FRET biosensor usually consists of one donor and one acceptor fluorescent protein, a substrate molecule that changes conformation upon binding the molecule of interest, and sometimes, a linker of a few amino acids that joins the substrate and fluorophores. The substrate's binding induces a measurable energy transfer ...
