NDLI: 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

Content Provider	Journal of Biological Chemistry (JBC)
Author	Kitazawa, Masahiro Kubo, Yoshihiro Nakajo, Koichi
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.
Related Links	http://www.jbc.org/content/289/25/17597.abstract
Ending Page	17609
Starting Page	17597
Page Count	13
File Format	HTM / HTML PDF
ISSN	00219258
Journal	Journal of Biological Chemistry (JBC)
Issue Number	25
Volume Number	289
DOI	10.1074/jbc.M114.563452
e-ISSN	1083351X
Language	English
Publisher	American Society for Biochemistry and Molecular Biology
Publisher Date	2014-06-20
Access Restriction	Open
Subject Keyword	Electrophysiology Fluorescence Imaging Ion Channel Potassium Channel Protein Complex K+ Channel-interacting Protein (KChIP) Single Molecule Imaging Stoichiometry Molecular Biophysics
Content Type	Text
Resource Type	Article
Subject	Cell Biology Biochemistry Molecular Biology

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in

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*

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

Co-assembly of Kv4 α Subunits with K+ Channel-interacting Protein 2 Stabilizes Protein Expression and Promotes Surface Retention of Channel Complexes

Kv4.2 and Accessory Dipeptidyl Peptidase-like Protein 10 (DPP10) Subunit Preferentially Form a 4:2 (Kv4.2:DPP10) Channel Complex

N-terminal Isoforms of the Large-conductance Ca2+-activated K+ Channel Are Differentially Modulated by the Auxiliary β1-Subunit

Multiple Kv Channel-interacting Proteins Contain an N-terminal Transmembrane Domain That Regulates Kv4 Channel Trafficking and Gating

Modulation of the Voltage-gated Potassium Channel (Kv4.3) and the Auxiliary Protein (KChIP3) Interactions by the Current Activator NS5806

A polybasic motif in alternatively spliced KChIP2 isoforms prevents Ca2+ regulation of Kv4 channels

SUMOylation of the Kv4.2 Ternary Complex Increases Surface Expression and Current Amplitude by Reducing Internalization in HEK 293 Cells

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

Similar Documents

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*

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

Co-assembly of Kv4 α Subunits with K+ Channel-interacting Protein 2 Stabilizes Protein Expression and Promotes Surface Retention of Channel Complexes

Kv4.2 and Accessory Dipeptidyl Peptidase-like Protein 10 (DPP10) Subunit Preferentially Form a 4:2 (Kv4.2:DPP10) Channel Complex

N-terminal Isoforms of the Large-conductance Ca2+-activated K+ Channel Are Differentially Modulated by the Auxiliary β1-Subunit

Multiple Kv Channel-interacting Proteins Contain an N-terminal Transmembrane Domain That Regulates Kv4 Channel Trafficking and Gating

Modulation of the Voltage-gated Potassium Channel (Kv4.3) and the Auxiliary Protein (KChIP3) Interactions by the Current Activator NS5806

A polybasic motif in alternatively spliced KChIP2 isoforms prevents Ca2+ regulation of Kv4 channels

SUMOylation of the Kv4.2 Ternary Complex Increases Surface Expression and Current Amplitude by Reducing Internalization in HEK 293 Cells

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