Project Details
Projekt
Tuning wavelength and G protein specificty of Melanopsin for optogenetic control of G protein signaling pathways.
Applicants
Professor Dr. Tobias Brügmann; Professor Dr. Klaus Gerwert; Professor Dr. Stefan Herlitze
Subject Area
Molecular Biology and Physiology of Neurons and Glial Cells
Biophysics
Structural Biology
Biophysics
Structural Biology
Term
from 2016 to 2024
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 315212873
Our goal is to create optogenetic tools for independent control of intracellular G protein signals activated by the Gi/o and Gs, but in particular the Gq/11 pathway. These tools will be established using vertebrate melanopsin and neuropsin as light-activated G protein coupled receptor (GPCR), which activates Gq11 and Gi/o pathways in neurons, heart and heterologous expression systems. Computer models (Gerwert lab) will predict amino acid position critical for wavelength specificity, bistabililty, and G protein selectivity. The functional analysis (Brügmann & Herlitze lab) of amino acid changes at predicted position using electrophysiological recordings and imaging techniques will provide experimental feedback for new working models of melanopsin and neuropsin and their G protein selectivity. Vertebrate melanopsin and neuropsin as bistable pigments are preferable over commonly used opsins to control G protein pathways in particular for highly-repetitive in vivo applications, because it can be switched on and off by two different wavelength of visible light. In addition, sustained G protein signals can be activated by short light pulses, reducing phototoxicity. These tools will be applicable for controlling every GPCR coupling to the common G protein pathways, such as dopamine, adreno, metabotropic glutamate, histamine or orexin receptor pathways without change in signal kinetics. Because of our long-standing interest in serotonin, we will tailor these tools to specifically control G protein signals in 5HT receptor signaling domains. The ultimate goal is to control two signaling pathways simultaneously, but independently by two different wavelength of light to understand how G protein signals synergistically and/or independently act to modulate cell function and behavior. In order to perform these experiments we have assembled a team of three experts on the development of optogenetic tools (Brügmann & Herlitze) and computational modeling of protein structures (Gerwert).
DFG Programme
Priority Programmes
