Journal article
Extracellular Interaction of the Voltage-dependent Ca2+ Channel α2δ and α1 Subunits
The Journal of biological chemistry, Vol.272(29), pp.18508-18512
07/18/1997
DOI: 10.1074/jbc.272.29.18508
PMID: 9218497
Abstract
The role of the extracellular domain of the voltage-dependent Ca2+ channel α2δ subunit in assembly with the α1Csubunit was investigated. Transiently transfected tsA201 cells processed the α2δ subunit properly as disulfide linkages and cleavage sites between the α2 and δ subunits were shown to be similar to native channel protein. Coimmunoprecipitation experiments demonstrated that in the absence of δ subunits, α2 subunits do not assemble with α1 subunits. Furthermore, the transmembrane and cytoplasmic sequences in δ can be exchanged with those of an unrelated protein without any effect on the association between the α2δ and α1 proteins. Extracellular domains of the α2δ subunit are also shown to be responsible for increasing the binding affinity of [3H]PN200-110 (isopropyl-4-(2,1,3-benzoxadiazol-4-yl)-1,4-dihydro-2,6-dimethyl-5-([3H]methoxycarbonyl)-pyridine-3-carboxylate) for the α1C subunit. Investigation of the corresponding interaction site on the α1 subunit revealed that although tryptic peptides containing repeat III of native α1S subunit remain in association with the α2δ subunit during wheat germ agglutinin chromatography, repeat III by itself is not sufficient for assembly with the α2δ subunit. Our results suggest that the α2δ subunit likely interacts with more than one extracellular loop of the α1 subunit.
Details
- Title: Subtitle
- Extracellular Interaction of the Voltage-dependent Ca2+ Channel α2δ and α1 Subunits
- Creators
- Christina A Gurnett - Department of Physiology and Biophysics, Howard Hughes Medical Institute, University of Iowa College of Medicine, Iowa City, Iowa 52242Ricardo Felix - Department of Physiology and Biophysics, Howard Hughes Medical Institute, University of Iowa College of Medicine, Iowa City, Iowa 52242Kevin P Campbell - Department of Neurology, Howard Hughes Medical Institute, University of Iowa College of Medicine, Iowa City, Iowa 52242
- Resource Type
- Journal article
- Publication Details
- The Journal of biological chemistry, Vol.272(29), pp.18508-18512
- DOI
- 10.1074/jbc.272.29.18508
- PMID
- 9218497
- NLM abbreviation
- J Biol Chem
- ISSN
- 0021-9258
- eISSN
- 1083-351X
- Publisher
- Elsevier Inc
- Language
- English
- Date published
- 07/18/1997
- Academic Unit
- Neurology; Molecular Physiology and Biophysics; Iowa Neuroscience Institute
- Record Identifier
- 9984068266002771
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