Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
J Biol Chem
2014 Jun 20;28925:17597-609. doi: 10.1074/jbc.M114.563452.
Show Gene links
Show Anatomy links
The stoichiometry and biophysical properties of the Kv4 potassium channel complex with K+ channel-interacting protein (KChIP) subunits are variable, depending on the relative expression level.
Kitazawa M
,
Kubo Y
,
Nakajo K
.
???displayArticle.abstract???
Kv4 is a voltage-gated K(+) channel, which underlies somatodendritic subthreshold A-type current (ISA) and cardiac transient outward K(+) (Ito) current. Various ion channel properties of Kv4 are known to be modulated by its auxiliary subunits, such as K(+) channel-interacting protein (KChIP) or dipeptidyl peptidase-like protein. KChIP is a cytoplasmic protein and increases the current amplitude, decelerates the inactivation, and accelerates the recovery from inactivation of Kv4. Crystal structure analysis demonstrated that Kv4 and KChIP form an octameric complex with four Kv4 subunits and four KChIP subunits. However, it remains unknown whether the Kv4·KChIP complex can have a different stoichiometry other than 4:4. In this study, we expressed Kv4.2 and KChIP4 with various ratios in Xenopus oocytes and observed that the biophysical properties of Kv4.2 gradually changed with the increase in co-expressed KChIP4. The tandem repeat constructs of Kv4.2 and KChIP4 revealed that the 4:4 (Kv4.2/KChIP4) channel shows faster recovery than the 4:2 channel, suggesting that the biophysical properties of Kv4.2 change, depending on the number of bound KChIP4s. Subunit counting by single-molecule imaging revealed that the bound number of KChIP4 in each Kv4.2·KChIP4 complex was dependent on the expression level of KChIP4. Taken together, we conclude that the stoichiometry of Kv4·KChIP complex is variable, and the biophysical properties of Kv4 change depending on the number of bound KChIP subunits.
An,
Modulation of A-type potassium channels by a family of calcium sensors.
2000, Pubmed,
Xenbase
An,
Modulation of A-type potassium channels by a family of calcium sensors.
2000,
Pubmed
,
Xenbase
Beck,
Remodelling inactivation gating of Kv4 channels by KChIP1, a small-molecular-weight calcium-binding protein.
2002,
Pubmed
,
Xenbase
Bradford,
A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding.
1976,
Pubmed
Burgoyne,
Neuronal calcium sensor proteins: generating diversity in neuronal Ca2+ signalling.
2007,
Pubmed
Chen,
Deletion of Kv4.2 gene eliminates dendritic A-type K+ current and enhances induction of long-term potentiation in hippocampal CA1 pyramidal neurons.
2006,
Pubmed
Dixon,
Role of the Kv4.3 K+ channel in ventricular muscle. A molecular correlate for the transient outward current.
1996,
Pubmed
Foeger,
Co-assembly of Kv4 {alpha} subunits with K+ channel-interacting protein 2 stabilizes protein expression and promotes surface retention of channel complexes.
2010,
Pubmed
Gebauer,
N-type inactivation features of Kv4.2 channel gating.
2004,
Pubmed
Hasdemir,
Traffic of Kv4 K+ channels mediated by KChIP1 is via a novel post-ER vesicular pathway.
2005,
Pubmed
Hastie,
AMPA receptor/TARP stoichiometry visualized by single-molecule subunit counting.
2013,
Pubmed
,
Xenbase
Hatano,
Functional interaction between KChIP1 and GFP-fused Kv4.3L co-expressed in HEK293 cells.
2002,
Pubmed
Holmqvist,
Elimination of fast inactivation in Kv4 A-type potassium channels by an auxiliary subunit domain.
2002,
Pubmed
,
Xenbase
Hovind,
The "structurally minimal" isoform KChIP2d modulates recovery of K(v)4.3 N-terminal deletion mutant Δ2-39.
2011,
Pubmed
,
Xenbase
Jerng,
Multiple Kv channel-interacting proteins contain an N-terminal transmembrane domain that regulates Kv4 channel trafficking and gating.
2008,
Pubmed
Jerng,
Multiprotein assembly of Kv4.2, KChIP3 and DPP10 produces ternary channel complexes with ISA-like properties.
2005,
Pubmed
,
Xenbase
Jerng,
Molecular physiology and modulation of somatodendritic A-type potassium channels.
2004,
Pubmed
Jeyaraj,
Circadian rhythms govern cardiac repolarization and arrhythmogenesis.
2012,
Pubmed
Kim,
Ito channels are octomeric complexes with four subunits of each Kv4.2 and K+ channel-interacting protein 2.
2004,
Pubmed
,
Xenbase
Kim,
Three-dimensional structure of I(to); Kv4.2-KChIP2 ion channels by electron microscopy at 21 Angstrom resolution.
2004,
Pubmed
Liang,
Structural Insights into KChIP4a Modulation of Kv4.3 Inactivation.
2009,
Pubmed
,
Xenbase
Morohashi,
Molecular cloning and characterization of CALP/KChIP4, a novel EF-hand protein interacting with presenilin 2 and voltage-gated potassium channel subunit Kv4.
2002,
Pubmed
Nadal,
The CD26-related dipeptidyl aminopeptidase-like protein DPPX is a critical component of neuronal A-type K+ channels.
2003,
Pubmed
,
Xenbase
Nakajo,
Stoichiometry of the KCNQ1 - KCNE1 ion channel complex.
2010,
Pubmed
,
Xenbase
Nakamura,
A role for frequenin, a Ca2+-binding protein, as a regulator of Kv4 K+-currents.
2001,
Pubmed
,
Xenbase
Nerbonne,
Molecular physiology of cardiac repolarization.
2005,
Pubmed
Norris,
Interdependent roles for accessory KChIP2, KChIP3, and KChIP4 subunits in the generation of Kv4-encoded IA channels in cortical pyramidal neurons.
2010,
Pubmed
Patel,
Regulation of Kv4.3 voltage-dependent gating kinetics by KChIP2 isoforms.
2004,
Pubmed
,
Xenbase
Patel,
Elucidating KChIP effects on Kv4.3 inactivation and recovery kinetics with a minimal KChIP2 isoform.
2002,
Pubmed
,
Xenbase
Pioletti,
Three-dimensional structure of the KChIP1-Kv4.3 T1 complex reveals a cross-shaped octamer.
2006,
Pubmed
,
Xenbase
Pongs,
Ancillary subunits associated with voltage-dependent K+ channels.
2010,
Pubmed
Ren,
Transmembrane interaction mediates complex formation between peptidase homologues and Kv4 channels.
2005,
Pubmed
Ren,
Effective association of Kv channel-interacting proteins with Kv4 channel is mediated with their unique core peptide.
2003,
Pubmed
Rhodes,
KChIPs and Kv4 alpha subunits as integral components of A-type potassium channels in mammalian brain.
2004,
Pubmed
Scannevin,
Two N-terminal domains of Kv4 K(+) channels regulate binding to and modulation by KChIP1.
2004,
Pubmed
Seikel,
Convergent modulation of Kv4.2 channel alpha subunits by structurally distinct DPPX and KChIP auxiliary subunits.
2009,
Pubmed
Serôdio,
Identification of molecular components of A-type channels activating at subthreshold potentials.
1994,
Pubmed
,
Xenbase
Shibata,
A fundamental role for KChIPs in determining the molecular properties and trafficking of Kv4.2 potassium channels.
2003,
Pubmed
Tang,
Auxiliary KChIP4a suppresses A-type K+ current through endoplasmic reticulum (ER) retention and promoting closed-state inactivation of Kv4 channels.
2013,
Pubmed
Tombola,
The voltage-gated proton channel Hv1 has two pores, each controlled by one voltage sensor.
2008,
Pubmed
,
Xenbase
Ulbrich,
Subunit counting in membrane-bound proteins.
2007,
Pubmed
,
Xenbase
Wang,
Structural basis for modulation of Kv4 K+ channels by auxiliary KChIP subunits.
2007,
Pubmed
,
Xenbase
Wang,
Modulation by clamping: Kv4 and KChIP interactions.
2008,
Pubmed
Yamashita,
Circadian variation of cardiac K+ channel gene expression.
2003,
Pubmed
Yu,
Structural and molecular basis of the assembly of the TRPP2/PKD1 complex.
2009,
Pubmed
,
Xenbase
Zagha,
DPP10 modulates Kv4-mediated A-type potassium channels.
2005,
Pubmed
Zhou,
Structural insights into the functional interaction of KChIP1 with Shal-type K(+) channels.
2004,
Pubmed