Modulation of Pore Opening of Eukaryotic Sodium Channels by π-Helices in S6.

ABSTRACT: Voltage-gated sodium channels are heterotetrameric sodium selective ion channels that play a central role in electrical signaling in excitable cells. With recent advances in structural biology, structures of eukaryotic sodium channels have been captured in several distinct conformations corresponding to different functional states. The secondary structure of the pore lining S6 helices of subunits DI, DII, and DIV has been captured with both short π-helix stretches and in fully α-helical conformations. The relevance of these secondary structure elements for pore gating is not yet understood. Here, we propose that a π-helix in at least DI-S6, DIII-S6, and DIV-S6 results in a fully conductive state. On the other hand, the absence of π-helix in either DI-S6 or DIV-S6 yields a subconductance st

SUBMITTER: Choudhury K 

PROVIDER: S-EPMC10316397 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature