Subunit requirements for Torpedo AChR channel expression: a specific role for the delta-subunit in voltage-dependent gating
- PMID: 1433281
- DOI: 10.1007/BF00232911
Subunit requirements for Torpedo AChR channel expression: a specific role for the delta-subunit in voltage-dependent gating
Abstract
This study examines the subunit requirement for Torpedo acetylcholine receptor (AChR) channel expression and the influence of non-alpha-subunit deletions on single AChR-channel currents. Xenopus oocytes injected with subunit combinations deficient in single non-alpha-subunit mRNA transcripts display the following order of ACh sensitivity: beta-less > gamma-less > delta-less. Oocytes injected with only the alpha-subunit and one non-alpha-subunit display the order: alpha delta > alpha gamma > alpha beta. These sequences indicate the effectiveness of non-alpha-subunit substitution is delta > gamma > beta. Single AChR-channel currents measured in oocytes deficient in either beta or gamma display conductance and voltage-sensitive burst kinetics similar to the wild-type channel. In contrast, the delta-less combination express channels with burst kinetics that are relatively faster and voltage insensitive. These results indicate that either a specific structural domain in the delta-subunit or its specific interactions with the alpha-subunit contribute to the voltage-dependent gating of the Torpedo AChR channel.
Similar articles
-
Single-channel properties of mouse-Torpedo acetylcholine receptor hybrids expressed in Xenopus oocytes.Brain Res Mol Brain Res. 1991 Jun;10(3):203-11. doi: 10.1016/0169-328x(91)90062-3. Brain Res Mol Brain Res. 1991. PMID: 1715966
-
Functional acetylcholine receptors expressed in Xenopus oocytes after injection of Torpedo beta, gamma, and delta subunit RNAs are a consequence of endogenous oocyte gene expression.Mol Pharmacol. 1990 Mar;37(3):423-8. Mol Pharmacol. 1990. PMID: 1690347
-
Patch clamp measurements on Xenopus laevis oocytes: currents through endogenous channels and implanted acetylcholine receptor and sodium channels.Pflugers Arch. 1986 Dec;407(6):577-88. doi: 10.1007/BF00582635. Pflugers Arch. 1986. PMID: 2432468
-
Spontaneous and agonist-induced openings of an acetylcholine receptor channel composed of bovine muscle alpha-, beta- and delta-subunits.Pflugers Arch. 1990 Oct;417(2):129-35. doi: 10.1007/BF00370689. Pflugers Arch. 1990. PMID: 1707514
-
Mouse-Torpedo chimeric alpha-subunit used to probe channel-gating determinants on the nicotinic acetylcholine receptor primary sequence.Cell Mol Neurobiol. 1997 Feb;17(1):13-33. doi: 10.1023/a:1026372903352. Cell Mol Neurobiol. 1997. PMID: 9118205 Free PMC article.
Cited by
-
An acetylcholine receptor lacking both γ and ε subunits mediates transmission in zebrafish slow muscle synapses.J Gen Physiol. 2011 Sep;138(3):353-66. doi: 10.1085/jgp.201110649. Epub 2011 Aug 15. J Gen Physiol. 2011. PMID: 21844221 Free PMC article.
-
Serotonergic modulation of muscle acetylcholine receptors of different subunit composition.Proc Natl Acad Sci U S A. 1996 Apr 30;93(9):3990-4. doi: 10.1073/pnas.93.9.3990. Proc Natl Acad Sci U S A. 1996. PMID: 8633003 Free PMC article.
-
Expression of subunit-omitted mouse nicotinic acetylcholine receptors in Xenopus laevis oocytes.J Physiol. 1993 Oct;470:349-63. doi: 10.1113/jphysiol.1993.sp019862. J Physiol. 1993. PMID: 7508504 Free PMC article.
-
Serum choline activates mutant acetylcholine receptors that cause slow channel congenital myasthenic syndromes.Proc Natl Acad Sci U S A. 1999 Aug 31;96(18):10466-71. doi: 10.1073/pnas.96.18.10466. Proc Natl Acad Sci U S A. 1999. PMID: 10468632 Free PMC article.
-
Negatively charged amino acid residues in the nicotinic receptor delta subunit that contribute to the binding of acetylcholine.Proc Natl Acad Sci U S A. 1993 Jul 1;90(13):6285-9. doi: 10.1073/pnas.90.13.6285. Proc Natl Acad Sci U S A. 1993. PMID: 8327511 Free PMC article.