Voltage dependent activation of potassium channels is coupled to T1 domainstructure

Citation
Sj. Cushman et al., Voltage dependent activation of potassium channels is coupled to T1 domainstructure, NAT ST BIOL, 7(5), 2000, pp. 403-407
Citations number
45
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
NATURE STRUCTURAL BIOLOGY
ISSN journal
1072-8368 → ACNP
Volume
7
Issue
5
Year of publication
2000
Pages
403 - 407
Database
ISI
SICI code
1072-8368(200005)7:5<403:VDAOPC>2.0.ZU;2-A
Abstract
The T1 domain, a highly conserved cytoplasmic portion at the N-terminus of the voltage-dependent K+ channel (Kv) alpha-subunit, is responsible for dri ving and regulating the tetramerization of the alpha-subunits. Here we repo rt the identification of a set of mutations in the T1 domain that alter the gating properties of the Kv channel. Two mutants produce a leftward shift in the activation curve and slow the channel closing rate while a third mut ation produces a rightward shift in the activation curve and speeds the cha nnel closing rate. We have determined the crystal structures of T1 domains containing these mutations. Both of the leftward shifting mutants produce s imilar conformational changes in the putative membrane facing surface of th e T1 domain. These results suggest that the structure of the T1 domain in t his region is tightly coupled to the channel's gating states.