Bioelectricity under optical detection and manipulation: optical probes on ion channel proteins

Prof. Ehud Isacoff
Department of Molecular and Cell Biology, UC Berkeley

Proteins alter their functional state when they undergo structural rearrangements and when they change their interaction with other proteins. Our  aim is to create new methods for sensing and controlling protein structure and interaction in living cells and in reconstituted membrane systems.

1) Chemical photo-switches for the optical control of protein function. Along with Dirk Trauner (Chemistry) and Richard Kramer (Molecular and Cell Bio), we have developed an approach for the remote control manipulation of the functional state of a protein. The approach relies on novel chemical elements, which contain a photo-isomerizable moiety that can be switched back and forth between two photo-stationary states with different wavelengths of light. These elements are attached to the protein of interest and they function as photo-switches to turn that protein on and off in response to light.

2) Real-time optical detection of protein structure and function. We have developed optical methods that provide a real-time report of the structural rearrangements underlying functional transitions of proteins.

The photo-switching of proteins and the detection of their functional transitions can be done on purified preparations, in reconstituted systems, and in live cells and tissues. They provide for an optical I/O to protein-based nano-devices that can provide a solution to the problem of interfacing nano-machines to the macroscopic world of chips.