CRC 1078/1: Structural Dynamics of Channelrhodopsins (SP B01)


The proposed project aims at an elucidation of the mechanism governing ChR gating and transport. For the understanding of protonation dynamics that occur during activation (gating) of the channel and during transport of the ions across the membrane, the knowledge about structural rearrangements are of great importance . Based on a recently published 3D-structure of a ChR dark state, we will study protein dynamics and the contribution of individual amino acid residues to the function of ChR in more detail by employing NMR measurements on isotope-labeled recombinant protein. We will explore structural dynamics of the protein by comparing the open and closed states of the channel and provide an essential basis for the interpretation of protonation dynamics as studied in other B.projects. We will label ChR unifromly and site-specifically at key positions in and around the retinal-binding pocket and in sub-epitopes involved in channel gating, including reconstitution with labeled retinal. In a second approach we will crystallize photocycle intermediates of ChR with a strong focus on the open states. Accordingly, we will improve the solubilization procedure and find conditions for a stable and mono-disperse ChR preparation. We will optimize purification for the most promising ChRs and we will try to crystallize ChR in its open state in different detergents by classical approaches and in cubic lipid phases.


Principal Investigators
Hegemann, Peter Prof. Dr. (Details) (Experimental Biophysics)

Duration of Project
Start date: 01/2013
End date: 12/2020

Related umbrella project

Research Areas
Biophysics

Last updated on 2021-12-10 at 10:52