| Title : Mapping the alpha-subunit site photolabeled by the noncompetitive inhibitor [3H]quinacrine azide in the active state of the nicotinic acetylcholine receptor - DiPaola_1990_J.Biol.Chem_265_11017 |
| Author(s) : DiPaola M , Kao PN , Karlin A |
| Ref : Journal of Biological Chemistry , 265 :11017 , 1990 |
| Abstract : We have characterized the time-resolved labeling of a site on the Torpedo californica electrocyte acetylcholine receptor (ACHR) by the photoreactive noncompetitive inhibitor derivative quinacrine azide (QA). The dependence of [3H]QA labeling on acetylcholine (ACH) concentration and on time is consistent with the preferential labeling by [3H]QA of ACHR in the open state. The ACH-dependent [3H]QA labeling, which was associated predominantly with the alpha-subunit, was blocked by other noncompetitive inhibitors including quinacrine, chlorpromazine, proadifen, histrionicotoxin, and bupivacaine. alpha-Subunit from ACHR labeled with [3H]QA 20 ms after the addition of ACH was cleaved with CNBr, and the fragments were separated by high pressure liquid chromatography. A peptide containing a major site of specific labeling was purified on two different reverse-phase columns. By N-terminal sequencing, amino acid composition, binding to mercurial-agarose, and apparent molecular weight, this [3H]QA-labeled peptide was identified as alpha-208-243, a CNBr fragment containing the putative membrane-spanning helix M1. |
| ESTHER : DiPaola_1990_J.Biol.Chem_265_11017 |
| PubMedSearch : DiPaola_1990_J.Biol.Chem_265_11017 |
| PubMedID: 2358450 |
DiPaola M, Kao PN, Karlin A (1990)
Mapping the alpha-subunit site photolabeled by the noncompetitive inhibitor [3H]quinacrine azide in the active state of the nicotinic acetylcholine receptor
Journal of Biological Chemistry
265 :11017
DiPaola M, Kao PN, Karlin A (1990)
Journal of Biological Chemistry
265 :11017