Biophysical Society Thematic Meeting - June 28-July 1, 2015

New Biological Frontiers Illuminated by Molecular Sensors and Actuators Monday Speaker Abstracts

Photodissociable Photoswitchable Dimeric Fluorescent Proteins Enable Optical Control of Kinase Activity Michael Lin Stanford University, USA. About twenty years ago, the cloning of fluorescent proteins catalyzed a revolution in biological research. With ideal characteristics as tags and as components of reporter proteins, fluorescent proteins enabled visualization of biological processes in living cells, with spatial detail and in real time. A second optical revolution is now in the making, with ongoing efforts to use light to control rather than to sense biological activities. While examples exist of adapting natural photoregulatory to regulate biology in mammalian cells, this approach has limitations. We have been exploring the hypothesis that fluorescent proteins can be engineered into ideal photoregulatory proteins as well. We recently engineered the photoswitchable fluorescent protein Dronpa into a photodissociable tetramer, then developed a design for caged proteins in which two copies of Dronpa are fused to a protein of interest so that tetramerization blocks protein activity and photodissociation activates it. We will present recent advances in improving the performance of photodissociable Dronpa domains and in generalizing the caged protein design to an important class of regulatory proteins, the kinases.

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