Premium
On the activation—inactivation coupling in Shaker potassium channels
Author(s) -
Lee Chyuan-Yih
Publication year - 1992
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(92)80976-n
Subject(s) - shaker , deprotonation , tyrosine , chemistry , potassium channel , biophysics , coupling (piping) , biochemistry , ion , materials science , biology , physics , organic chemistry , quantum mechanics , metallurgy , vibration
The ‘ball‐and‐chain’ model suggests the existence of a negative site which may attract the positively charged inactivation ball to occlude the pore when the channel is in the open state. For Shaker K + channels, we propose that the state‐dependent negative site be tryptophan‐435, which becomes negatively charged after receiving an electron from tyrosine‐445. The kinetic scheme for the channel's activation‐inactivation coupling as derived from the YW‐gated model resembles a successful ‘scheme 8’ proposed by Zagotta and Aldrich. Our model suggests that the final rapid voltage‐independent transition to the open state is due to the deprotonation of tyrosine‐445.