Journal article
Functional properties of the purified N-type Ca2+ channel from rabbit brain
The Journal of biological chemistry, Vol.269(9), pp.6716-6724
1994
DOI: 10.1016/S0021-9258(17)37434-3
PMID: 8120030
Abstract
N-type Ca2+ channels control a variety of key neuronal functions including transmitter release at synaptic terminals. The purified omega-conotoxin receptor from rabbit brain is a multisubunit complex composed of alpha 1B, alpha 2 delta, beta 3, and 95-kDa subunits. Immunoadsorption experiments confirm that the purified preparation does not contain alpha 1 subunits other than the omega-conotoxin-sensitive class B isoform. The functional properties of the purified channel have been analyzed further in lipid bilayers, and similarities to or differences from the native N-type Ca2+ channel have been outlined. Conserved properties include ion selectivity, open-time duration, and pharmacology (insensitivity to drugs affecting skeletal muscle L-type Ca2+ channels). Observed properties of the reconstituted channel which differ from the native channel include (a) sustained channel activity without Ca(2+)- or voltage-induced inactivation; (b) examples of extremely high open-state probability; (c) the absence of "run-down"; and (d) voltage independence of the Ca2+ channel gating. In addition, the conductance of the purified receptor is comprised between 7 and 27 picosiemens. Our results suggest that cellular components may play critical roles in the regulation of several biophysical properties and neuronal function of the native N-type Ca2+ channel.
Details
- Title: Subtitle
- Functional properties of the purified N-type Ca2+ channel from rabbit brain
- Creators
- Michel De Waard - Univ. Iowa coll. medicine, Howard Hughes medical inst., dep. physiology biophysics, Iowa City IA 52242, United StatesDerrick R Witcher - Univ. Iowa coll. medicine, Howard Hughes medical inst., dep. physiology biophysics, Iowa City IA 52242, United StatesKevin P Campbell - Univ. Iowa coll. medicine, Howard Hughes medical inst., dep. physiology biophysics, Iowa City IA 52242, United States
- Resource Type
- Journal article
- Publication Details
- The Journal of biological chemistry, Vol.269(9), pp.6716-6724
- DOI
- 10.1016/S0021-9258(17)37434-3
- PMID
- 8120030
- NLM abbreviation
- J Biol Chem
- ISSN
- 0021-9258
- eISSN
- 1083-351X
- Publisher
- American Society for Biochemistry and Molecular Biology; Bethesda, MD
- Language
- English
- Date published
- 1994
- Academic Unit
- Neurology; Molecular Physiology and Biophysics; Iowa Neuroscience Institute
- Record Identifier
- 9984068369802771
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