TY - JOUR
T1 - A mammalian transient type K+ channel, Rat Kv1.4, Has two potential domains that could produce rapid inactivation
AU - Kondoh, Shun Ichi
AU - Ishii, Kuniaki
AU - Nakamura, Yasuhiro
AU - Taira, Norio
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 1997/8/1
Y1 - 1997/8/1
N2 - The 'bail and chain' model has been shown to be suitable for explaining the rapid inactivation of voltage-dependent K+ channels. For the Drosophila Shaker K+ channel (ShB), the first 20 residues of the amino terminus have been identified as the inactivation ball that binds to the open channel pore and blocks ion flow (Hoshi, T., Zagotta, W. N., and Aldrich, R. W. (1990) Science 250, 533-38; Zagotta, W. N., Hoshi, T., and Aldrich, R. W. (1990) Science 250, 568-571). We studied the structural elements responsible for rapid inactivation of a mammalian transient type K+ channel (rat Kv1.4) by constructing various mutants in the amino terminus and expressing them in Xenopus oocytes. Although it has been reported that the initial 37 residues might form the inactivation ball for rat Kv1.4 (Tseng-Crank, J., Yao, J.-A., Berman M. F., and Tseng, G.-N. (1993) J. Gen. Physiol. 102, 1057-1083), we found that not only the initial 37 residues, but also the following region, residues 40-68, could function independently as an inactivation gate. Like the Shaker inactivation ball, both potential inactivation domains have a hydrophobic amino-terminal region and a hydrophilic carboxyl-terminal region having net positive charge, which is essential for the domains to function as an inactivation gate.
AB - The 'bail and chain' model has been shown to be suitable for explaining the rapid inactivation of voltage-dependent K+ channels. For the Drosophila Shaker K+ channel (ShB), the first 20 residues of the amino terminus have been identified as the inactivation ball that binds to the open channel pore and blocks ion flow (Hoshi, T., Zagotta, W. N., and Aldrich, R. W. (1990) Science 250, 533-38; Zagotta, W. N., Hoshi, T., and Aldrich, R. W. (1990) Science 250, 568-571). We studied the structural elements responsible for rapid inactivation of a mammalian transient type K+ channel (rat Kv1.4) by constructing various mutants in the amino terminus and expressing them in Xenopus oocytes. Although it has been reported that the initial 37 residues might form the inactivation ball for rat Kv1.4 (Tseng-Crank, J., Yao, J.-A., Berman M. F., and Tseng, G.-N. (1993) J. Gen. Physiol. 102, 1057-1083), we found that not only the initial 37 residues, but also the following region, residues 40-68, could function independently as an inactivation gate. Like the Shaker inactivation ball, both potential inactivation domains have a hydrophobic amino-terminal region and a hydrophilic carboxyl-terminal region having net positive charge, which is essential for the domains to function as an inactivation gate.
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U2 - 10.1074/jbc.272.31.19333
DO - 10.1074/jbc.272.31.19333
M3 - Article
C2 - 9235930
AN - SCOPUS:0030742577
VL - 272
SP - 19333
EP - 19338
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 31
ER -