 |
 Previous Article | Next Article 
The Journal of Neuroscience, March 1, 2000, 20(5):1685-1693
Coexpression of Cloned  1B,  2a, and
2/ Subunits Produces
Non-Inactivating Calcium Currents Similar to Those
Found in Bovine Chromaffin Cells
Anne L.
Cahill,
Joyce H.
Hurley, and
Aaron P.
Fox
The Department of Neurobiology, Pharmacology, and Physiology, The
University of Chicago, Chicago, Illinois 60637
Chromaffin cells express N-type calcium channels identified
on the basis of their high sensitivity to block by  -conotoxin GVIA (-CgTx GVIA). In contrast to neuronal N-type calcium
currents that inactivate during long depolarizations and that require
negative holding potentials to remove inactivation, many chromaffin
cells exhibit N-type calcium channel currents that show little
inactivation during maintained depolarizations and that exhibit no
decrease in channel availability at depolarized holding potentials.
N-type calcium channels are thought to be produced by combination of the pore-forming  1B subunit and accessory  and
2/ subunits. To examine the molecular
composition of the non-inactivating N-type calcium channel, we cloned
the 1B and accessory (1b,
1c, 2a, 2b,
and 3a) subunits found in bovine chromaffin
cells. Expression of the subunits in either Xenopus
oocytes or human embryonic kidney 293 cells produced
high-threshold calcium currents that were blocked by -CgTx GVIA.
Coexpression of bovine 1B with 1b,
1c, 2b, or 3a
produced currents that were holding potential dependent. In contrast,
coexpression of bovine 1B with 2a
produced holding potential-independent calcium currents that closely
mimicked native non-inactivating currents, suggesting that
non-inactivating N-type channels consist of bovine
1B, 2/, and
2a.
Key words:
N-type calcium channel; 1B subunit;
subunits; non-inactivating calcium current; chromaffin cells; voltage-dependent calcium channel
Copyright © 2000 Society for Neuroscience 0270-6474/00/2051685-09$05.00/0
This article has been cited by other articles:
|
|
|
|
 
R. C. E. Wykes, C. S. Bauer, S. U. Khan, J. L. Weiss, and E. P. Seward
Differential Regulation of Endogenous N- and P/Q-Type Ca2+ Channel Inactivation by Ca2+/Calmodulin Impacts on Their Ability to Support Exocytosis in Chromaffin Cells
J. Neurosci.,
May 9, 2007;
27(19):
5236 - 5248.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. B. Harkins, A. L. Cahill, J. F. Powers, A. S. Tischler, and A. P. Fox
Deletion of the synaptic protein interaction site of the N-type (CaV2.2) calcium channel inhibits secretion in mouse pheochromocytoma cells
PNAS,
October 19, 2004;
101(42):
15219 - 15224.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. H Hurley, A. L Cahill, M. Wang, and A. P Fox
Syntaxin 1A regulation of weakly inactivating N-type Ca2+ channels
J. Physiol.,
October 15, 2004;
560(2):
351 - 363.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. B. Harkins, A. L. Cahill, J. F. Powers, A. S. Tischler, and A. P. Fox
Expression of Recombinant Calcium Channels Support Secretion in a Mouse Pheochromocytoma Cell Line
J Neurophysiol,
October 1, 2003;
90(4):
2325 - 2333.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Peng, R. K. Hajela, and W. D. Atchison
Characteristics of Block by Pb2+ of Function of Human Neuronal L-, N-, and R-Type Ca2+ Channels Transiently Expressed in Human Embryonic Kidney 293 Cells
Mol. Pharmacol.,
December 1, 2002;
62(6):
1418 - 1430.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. P M Currie and A. P Fox
Differential facilitation of N- and P/Q-type calcium channels during trains of action potential-like waveforms
J. Physiol.,
March 1, 2002;
539(2):
419 - 431.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Chen, X. Zheng, K. L Schulze, T. Morris, H. Bellen, and E. F Stanley
Enhancement of presynaptic calcium current by cysteine string protein
J. Physiol.,
January 15, 2002;
538(2):
383 - 389.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. Albillos, E. Neher, and T. Moser
R-Type Ca2+ Channels Are Coupled to the Rapid Component of Secretion in Mouse Adrenal Slice Chromaffin Cells
J. Neurosci.,
November 15, 2000;
20(22):
8323 - 8330.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. H. Hurley, A. L. Cahill, K. P. M. Currie, and A. P. Fox
The role of dynamic palmitoylation in Ca2+ channel inactivation
PNAS,
July 12, 2000;
(2000)
160589697.
[Abstract]
[Full Text]
|
|
|
|
|
|
|
J. Q. Pan and D. Lipscombe
Alternative Splicing in the Cytoplasmic II-III Loop of the N-Type Ca Channel alpha 1B Subunit: Functional Differences Are beta Subunit-Specific
J. Neurosci.,
July 1, 2000;
20(13):
4769 - 4775.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
A. Koschak, D. Reimer, I. Huber, M. Grabner, H. Glossmann, J. Engel, and J. Striessnig
alpha 1D (Cav1.3) Subunits Can Form L-type Ca2+ Channels Activating at Negative Voltages
J. Biol. Chem.,
June 15, 2001;
276(25):
22100 - 22106.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
J. H. Hurley, A. L. Cahill, K. P. M. Currie, and A. P. Fox
The role of dynamic palmitoylation in Ca2+ channel inactivation
PNAS,
August 1, 2000;
97(16):
9293 - 9298.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
K. P.M. Currie and A. P. Fox
Differential facilitation of N- and P/Q-type calcium channels during trains of action potential-like waveforms
J. Physiol.,
January 25, 2002;
(2002)
200101320.
[Abstract]
[PDF]
|
|
|
|
|
|
|
S. Chen, X. Zheng, K. L. Schulze, T. Morris, H. Bellen, and E. F. Stanley
Enhancement of presynaptic calcium current by cysteine string protein
J. Physiol.,
December 19, 2001;
(2001)
200101339.
[Abstract]
[PDF]
|
|
|
|
