6EIG

Crystal structure of N24Q/C128T mutant of Channelrhodopsin 2

Summary for 6EIG

• Entry DOI: 10.2210/pdb6eig/pdb
• Descriptor: Archaeal-type opsin 2, (2R)-2,3-dihydroxypropyl (9Z)-octadec-9-enoate, PHOSPHATE ION, ... (5 entities in total)
• Functional Keywords: retinal protein, ion transport, membrane protein
• Biological source: Chlamydomonas reinhardtii
• Total number of polymer chains: 2
• Total formula weight: 73672.61

Authors

Kovalev, K.,Borshchevskiy, V.,Volkov, O.,Polovinkin, V.,Marin, E.,Balandin, T.,Astashkin, R.,Bamann, C.,Bueldt, G.,Willlbold, D.,Popov, A.,Bamberg, E.,Gordeliy, V. (deposition date: 2017-09-19, release date: 2017-12-06, Last modification date: 2024-01-17)

Primary citation

Volkov, O.,Kovalev, K.,Polovinkin, V.,Borshchevskiy, V.,Bamann, C.,Astashkin, R.,Marin, E.,Popov, A.,Balandin, T.,Willbold, D.,Buldt, G.,Bamberg, E.,Gordeliy, V.
Structural insights into ion conduction by channelrhodopsin 2.
Science, 358:-, 2017

PubMed Abstract: The light-gated ion channel channelrhodopsin 2 (ChR2) from is a major optogenetic tool. Photon absorption starts a well-characterized photocycle, but the structural basis for the regulation of channel opening remains unclear. We present high-resolution structures of ChR2 and the C128T mutant, which has a markedly increased open-state lifetime. The structure reveals two cavities on the intracellular side and two cavities on the extracellular side. They are connected by extended hydrogen-bonding networks involving water molecules and side-chain residues. Central is the retinal Schiff base that controls and synchronizes three gates that separate the cavities. Separate from this network is the DC gate that comprises a water-mediated bond between C128 and D156 and interacts directly with the retinal Schiff base. Comparison with the C128T structure reveals a direct connection of the DC gate to the central gate and suggests how the gating mechanism is affected by subtle tuning of the Schiff base's interactions.

PubMed: 29170206
DOI: 10.1126/science.aan8862

Experimental method

X-RAY DIFFRACTION (2.7 Å)