Molecular properties of muscarinic acetylcholine receptors.

  • Haga T
  • 77


    Mendeley users who have this article in their library.
  • 32


    Citations of this article.


Muscarinic acetylcholine receptors, which comprise five subtypes (M1-M5 receptors), are expressed in both the CNS and PNS (particularly the target organs of parasympathetic neurons). M1-M5 receptors are integral membrane proteins with seven transmembrane segments, bind with acetylcholine (ACh) in the extracellular phase, and thereafter interact with and activate GTP-binding regulatory proteins (G proteins) in the intracellular phase: M1, M3, and M5 receptors interact with Gq-type G proteins, and M2 and M4 receptors with Gi/Go-type G proteins. Activated G proteins initiate a number of intracellular signal transduction systems. Agonist-bound muscarinic receptors are phosphorylated by G protein-coupled receptor kinases, which initiate their desensitization through uncoupling from G proteins, receptor internalization, and receptor breakdown (down regulation). Recently the crystal structures of M2 and M3 receptors were determined and are expected to contribute to the development of drugs targeted to muscarinic receptors. This paper summarizes the molecular properties of muscarinic receptors with reference to the historical background and bias to studies performed in our laboratories.

Author-supplied keywords

  • Acetylcholine
  • Acetylcholine: chemistry
  • Acetylcholine: metabolism
  • Animals
  • Central Nervous System
  • Central Nervous System: metabolism
  • Crystallography, X-Ray
  • G-Protein-Coupled Receptor Kinases
  • G-Protein-Coupled Receptor Kinases: chemistry
  • G-Protein-Coupled Receptor Kinases: metabolism
  • GTP-Binding Protein alpha Subunits, Gi-Go
  • GTP-Binding Protein alpha Subunits, Gi-Go: chemist
  • GTP-Binding Protein alpha Subunits, Gi-Go: metabol
  • GTP-Binding Protein alpha Subunits, Gq-G11
  • GTP-Binding Protein alpha Subunits, Gq-G11: chemis
  • GTP-Binding Protein alpha Subunits, Gq-G11: metabo
  • Humans
  • Parasympathetic Nervous System
  • Parasympathetic Nervous System: metabolism
  • Phosphorylation
  • Phosphorylation: physiology
  • Receptors, Muscarinic
  • Receptors, Muscarinic: chemistry
  • Receptors, Muscarinic: metabolism
  • Signal Transduction
  • Signal Transduction: physiology
  • Structure-Activity Relationship

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

Get full text


  • Tatsuya Haga

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free