Format

Send to

Choose Destination
See comment in PubMed Commons below
Mol Pharmacol. 2003 Feb;63(2):332-41.

Alternate stoichiometries of alpha4beta2 nicotinic acetylcholine receptors.

Author information

  • 1Department of Neuroscience, University of Pennsylvania Medical School, Philadelphia, Pennsylvania 19104, USA.

Abstract

Two functional types of nicotinic acetylcholine receptors (nAChRs) are expressed when human embryonic kidney cells are permanently transfected with equal amounts of human alpha4 and beta2 subunit cDNAs. Most (82%) of these nAChRs exhibit an EC(50) of 74 +/- 6 microM for ACh, a much lower sensitivity than the remaining fraction (EC(50) of 0.7 +/- 0.4 microM) or than expected from expression of equal amounts of alpha4 and beta2 mRNAs in Xenopus laevis oocytes. We have found three conditions that can increase the number of nAChRs with high sensitivity to activation. These are: 1) transient transfection with additional beta2 subunits, 2) overnight incubation in nicotine, or 3) overnight culture at 29 degrees C. Using metabolic labeling with [(35)S]methionine to measure subunit stoichiometry, we found that the majority of nAChRs had a stoichiometry of (alpha4)(3)(beta2)(2). Overnight treatment with nicotine increased the number of nAChRs and increased the proportion of the (alpha4)(2)(beta2)(3) stoichiometry. Alternate alpha4beta2 nAChR stoichiometries with distinct functional properties raise the possibility for an interesting mode of synaptic regulation for nicotinic signaling in the mammalian brain.

PMID:
12527804
[PubMed - indexed for MEDLINE]
Free full text

LinkOut - more resources

Full Text Sources

Other Literature Sources

Molecular Biology Databases

PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire
    Loading ...
    Support Center