Optical Control of Protein Activity by Fluorescent Protein Domains

Abstract

Fluorescent proteins (FPs) are widely used as sensors of protein localization and activity, while other classes of light-absorbing proteins have been used for optogenetic control of proteins with light. Here we describe a previously unknown feature of a variant of the photochromic green FP Dronpa - the ability to undergo light-dependent dissociation and association, and use it to control protein activities with light. We created a fluorescent light-inducible protein (FLIP) design in which Dronpa domains are fused to both termini of an enzyme domain. In the dark, the Dronpa domains tetramerize and cage the protein, but light induces Dronpa dissociation and activates the protein. This method enabled optical control over guanine nucleotide exchange factor and protease domains without extensive screening. To our knowledge, this is the first case of a light-dependent interaction outside of natural light-responsive regulatory proteins, and this method also uniquely has self-reporting abilities. In ongoing work, we are examining the mechanism of caging by Dronpa domains in more detail and adapting the FLIP design to photochromic red FPs. Our findings extend the applications of FPs from exclusively sensing functions to also encompass optogenetic control. Correction et al.Biophysical JournalApril 16, 2013In Brief2013. Optical Control of Protein Activity by Fluorescent Protein Domains. Xin X. Zhou. Biophys. J. 104(2)s: 680a. Full-Text PDF Open Archive