J Physiol Wellcome Trust-funded researchers
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
QUICK SEARCH:   [advanced]


     

Physiology in Press

First published online on October 18, 2002.
 Copyright © 2002 by The Physiological Society
This Article
Right arrow Full Text (Rapid PDF)
Right arrow All Versions of this Article:
545/1/5    most recent
2002.031856v1
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Patel, S. P.
Right arrow Articles by Strauss, H. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Patel, S. P.
Right arrow Articles by Strauss, H. C.

Received August 30, 2002
Accepted after revision October 6, 2002

Elucidating KChIP effects on Kv4.3 inactivation and recovery kinetics with a minimal KChIP2 isoform

S. P. Patel1*, Donald L. Campbell1, and Harold C. Strauss1

1 Department of Physiology and Biophysics, University at Buffalo, State University of New York, 124 Sherman Hall, Buffalo, NY 14214, USA

* To whom correspondence should be addressed. E-mail: sppatel{at}acsu.buffalo.edu.

Kv channel interacting proteins (KChIPs) are Ca2+-binding proteins with four EF-hands. KChIPs modulate Kv4 channel gating by slowing inactivation kinetics and accelerating recovery kinetics. Thus, KChIPs are believed to be important regulators of Kv4 channels underlying transient outward K+ currents in many excitable cell types. We have cloned a structurally minimal KChIP2 isoform (KChIP2d) from ferret heart. KChIP2d corresponds to the final 70 C-terminal amino acids of other KChIPs and has only one EF-hand. We demonstrate that KChIP2d is a functional KChIP that both accelerates recovery and slows inactivation kinetics of Kv4.3, indicating that the minimal C-terminus can maintain KChIP regulatory properties. We utilize KChIP2d to further demonstrate that: (i) the EF-hand modulates effects on Kv4.3 inactivation but not recovery; (ii) Ca2+-dependent effects on Kv4.3 inactivation are mediated through a mechanism reflected in the slow time constant of inactivation; and (iii) a short stretch of amino acids exclusive of the EF-hand partially mediates Ca2+-independent effects on recovery. Our results demonstrate that distinct regions of a KChIP molecule are involved in modulating inactivation and recovery. The potential ability of KChIP EF-hands to sense intracellular Ca2+ levels and transduce these changes to alterations in Kv4 channel inactivation kinetics may serve as a mechanism allowing intracellular Ca2+ transients to modulate repolarization. KChIP2d is a valuable tool for elucidating structural domains of KChIPs involved in Kv4 channel regulation.




This article has been cited by other articles:


Home page
 J. Physiol.Home page
G. C. L. Bett and R. L. Rasmusson
Modification of K+ channel-drug interactions by ancillary subunits
J. Physiol., February 15, 2008; 586(4): 929 - 950.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
D. Van Hoorick, A. Raes, and D. J. Snyders
The aromatic cluster in KCHIP1b affects Kv4 inactivation gating
J. Physiol., September 15, 2007; 583(3): 959 - 969.
[Abstract] [Full Text] [PDF]

Home page
 Protein Sci.Home page
S. Rajagopal and S. B.H. Kent
Total chemical synthesis and biophysical characterization of the minimal isoform of the KChIP2 potassium channel regulatory subunit
Protein Sci., September 1, 2007; 16(9): 2056 - 2064.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
S. Koyama and S. B. Appel
A-type K+ Current of Dopamine and GABA Neurons in the Ventral Tegmental Area
J Neurophysiol, August 1, 2006; 96(2): 544 - 554.
[Abstract] [Full Text] [PDF]

Home page
 Circ. Res.Home page
C. F. Rossow, K. W. Dilly, and L. F. Santana
Differential Calcineurin/NFATc3 Activity Contributes to the Ito Transmural Gradient in the Mouse Heart
Circ. Res., May 26, 2006; 98(10): 1306 - 1313.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
V. Salvador-Recatala, W. J. Gallin, J. Abbruzzese, P. C. Ruben, and A. N. Spencer
A potassium channel (Kv4) cloned from the heart of the tunicate Ciona intestinalis and its modulation by a KChIP subunit
J. Exp. Biol., February 15, 2006; 209(4): 731 - 747.
[Abstract] [Full Text] [PDF]

Home page
 Physiol. Rev.Home page
J. M. Nerbonne and R. S. Kass
Molecular Physiology of Cardiac Repolarization
Physiol Rev, October 1, 2005; 85(4): 1205 - 1253.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Cell Physiol.Home page
G. P. Sergeant, S. Ohya, J. A. Reihill, B. A. Perrino, G. C. Amberg, Y. Imaizumi, B. Horowitz, K. M. Sanders, and S. D. Koh
Regulation of Kv4.3 currents by Ca2+/calmodulin-dependent protein kinase II
Am J Physiol Cell Physiol, February 1, 2005; 288(2): C304 - C313.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
S. Zicha, L. Xiao, S. Stafford, T. J. Cha, W. Han, A. Varro, and S. Nattel
Transmural expression of transient outward potassium current subunits in normal and failing canine and human hearts
J. Physiol., December 15, 2004; 561(3): 735 - 748.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
E. Perrier, R. Perrier, S. Richard, and J.-P. Benitah
Ca2+ Controls Functional Expression of the Cardiac K+ Transient Outward Current via the Calcineurin Pathway
J. Biol. Chem., September 24, 2004; 279(39): 40634 - 40639.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
S. Wang, V. E. Bondarenko, Y. Qu, M. J. Morales, R. L. Rasmusson, and H. C. Strauss
Activation properties of Kv4.3 channels: time, voltage and [K+]o dependence
J. Physiol., June 15, 2004; 557(3): 705 - 717.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
N. Decher, A. S. Barth, T. Gonzalez, K. Steinmeyer, and M. C. Sanguinetti
Novel KChIP2 isoforms increase functional diversity of transient outward potassium currents
J. Physiol., June 15, 2004; 557(3): 761 - 772.
[Abstract] [Full Text] [PDF]

Home page
 J. Physiol.Home page
S. P. Patel, R. Parai, R. Parai, and D. L. Campbell
Regulation of Kv4.3 voltage-dependent gating kinetics by KChIP2 isoforms
J. Physiol., May 15, 2004; 557(1): 19 - 41.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Heart Circ. Physiol.Home page
F. G. Akar, R. C. Wu, I. Deschenes, A. A. Armoundas, V. Piacentino III, S. R. Houser, and G. F. Tomaselli
Phenotypic differences in transient outward K+ current of human and canine ventricular myocytes: insights into molecular composition of ventricular Ito
Am J Physiol Heart Circ Physiol, February 1, 2004; 286(2): H602 - H609.
[Abstract] [Full Text] [PDF]

Home page
 J. Biol. Chem.Home page
R. Shibata, H. Misonou, C. R. Campomanes, A. E. Anderson, L. A. Schrader, L. C. Doliveira, K. I. Carroll, J. D. Sweatt, K. J. Rhodes, and J. S. Trimmer
A Fundamental Role for KChIPs in Determining the Molecular Properties and Trafficking of Kv4.2 Potassium Channels
J. Biol. Chem., September 19, 2003; 278(38): 36445 - 36454.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
Y. Zhang, J. N. MacLean, W. F. An, C. C. Lanning, and R. M. Harris-Warrick
KChIP1 and Frequenin Modify shal-Evoked Potassium Currents in Pyloric Neurons in the Lobster Stomatogastric Ganglion
J Neurophysiol, April 1, 2003; 89(4): 1902 - 1909.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Copyright © 2002 The Physiological Society.