Stabilizing the closed S6 gate in the Shaker Kv channel through modification of a hydrophobic seal.

ABSTRACT: The primary activation gate in K+ channels is thought to reside near the intracellular entrance to the ion conduction pore. In a previous study of the S6 activation gate in Shaker (Hackos et al., 2002), we found that mutation of V478 to W results in a channel that cannot conduct ions even though the voltage sensors are competent to translocate gating charge in response to membrane depolarization. In the present study we explore the mechanism underlying the nonconducting phenotype in V478W and compare it to that of W434F, a mutation located in an extracellular region of the pore that is nonconducting because the channel is predominantly found in an inactivated state. We began by examining whether the intracellular gate moves using probes that interact with the intracellular pore and by stud

SUBMITTER: Kitaguchi T 

PROVIDER: S-EPMC2233904 | biostudies-literature | 2004 Oct

REPOSITORIES: biostudies-literature