6KFH

Undocked hemichannel of an N-terminal deletion mutant of INX-6 in a nanodisc

Summary for 6KFH

• Entry DOI: 10.2210/pdb6kfh/pdb
• EMDB information: 9973
• Descriptor: Innexin-6 (1 entity in total)
• Functional Keywords: gap junctions, innexin, transport protein
• Biological source: Caenorhabditis elegans
• Total number of polymer chains: 8
• Total formula weight: 361390.13

Authors

Burendei, B.,Shinozaki, R.,Watanabe, M.,Terada, T.,Tani, K.,Fujiyoshi, Y.,Oshima, A. (deposition date: 2019-07-07, release date: 2020-02-12, Last modification date: 2020-03-11)

Primary citation

Burendei, B.,Shinozaki, R.,Watanabe, M.,Terada, T.,Tani, K.,Fujiyoshi, Y.,Oshima, A.
Cryo-EM structures of undocked innexin-6 hemichannels in phospholipids.
Sci Adv, 6:eaax3157-eaax3157, 2020

PubMed Abstract: Gap junctions form intercellular conduits with a large pore size whose closed and open states regulate communication between adjacent cells. The structural basis of the mechanism by which gap junctions close, however, remains uncertain. Here, we show the cryo-electron microscopy structures of innexin-6 (INX-6) gap junction proteins in an undocked hemichannel form. In the nanodisc-reconstituted structure of the wild-type INX-6 hemichannel, flat double-layer densities obstruct the channel pore. Comparison of the hemichannel structures of a wild-type INX-6 in detergent and nanodisc-reconstituted amino-terminal deletion mutant reveals that lipid-mediated amino-terminal rearrangement and pore obstruction occur upon nanodisc reconstitution. Together with molecular dynamics simulations and electrophysiology functional assays, our results provide insight into the closure of the INX-6 hemichannel in a lipid bilayer before docking of two hemichannels.

PubMed: 32095518
DOI: 10.1126/sciadv.aax3157

Experimental method

ELECTRON MICROSCOPY (3.6 Å)