Binding site of AChR: Difference between revisions
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Acetylcholine receptor is a member of pentameric ligand gated ion channels family,which share the similar structure. Pentameric ligand gated ion channels (pLGIC), or [http://en.wikipedia.org/wiki/Cys-loop_receptors Cys-loop receptors],are a group of transmembrane ion channel proteins which open to allow ions such as Na+, K+, Ca2+, or Cl- to pass through the membrane in response to the binding of a chemical messenger, such as a neurotransmitter<ref> Purves, Dale, George J. Augustine, David Fitzpatrick, William C. Hall, Anthony-Samuel LaMantia, James O. McNamara, and Leonard E. White (2008). Neuroscience. 4th ed. Sinauer Associates. pp. 156–7. ISBN 978-0-87893-697-7.</ref>. In overall organization, the <scene name='68/688431/Plgics/1'>pLGICs</scene> have five subunits. The five subunits are arranged in a barrel-like manner around a central symmetry axis that coincides with the ion permeation pathway.<ref>PMID:24167270</ref> In each subunit, the extracellular domin(ECD) of pLGIC encompasses 10β-strands that are organized as a sandwich of two tightly interacting β-sheets, while the transmembrane domain(TMD) folds into a bundle of four α-helices (M1, M2, M3, M4). | Acetylcholine receptor is a member of pentameric ligand gated ion channels family,which share the similar structure. Pentameric ligand gated ion channels (pLGIC), or [http://en.wikipedia.org/wiki/Cys-loop_receptors Cys-loop receptors],are a group of transmembrane ion channel proteins which open to allow ions such as Na+, K+, Ca2+, or Cl- to pass through the membrane in response to the binding of a chemical messenger, such as a neurotransmitter<ref> Purves, Dale, George J. Augustine, David Fitzpatrick, William C. Hall, Anthony-Samuel LaMantia, James O. McNamara, and Leonard E. White (2008). Neuroscience. 4th ed. Sinauer Associates. pp. 156–7. ISBN 978-0-87893-697-7.</ref>. In overall organization, the <scene name='68/688431/Plgics/1'>pLGICs</scene> have five subunits. The five subunits are arranged in a barrel-like manner around a central symmetry axis that coincides with the ion permeation pathway.<ref>PMID:24167270</ref> In each subunit, the extracellular domin(ECD) of pLGIC encompasses 10β-strands that are organized as a sandwich of two tightly interacting β-sheets, while the transmembrane domain(TMD) folds into a bundle of four α-helices (M1, M2, M3, M4). | ||
X-ray structure of homologues of the extracellular domain(ECD) of nAChRs have also been described:the acetylcholine binding protein(AChBP) co-crystallized with agonists and antagonists, and the ECD of α1-nAChRs. Most pLGICs undergo desensitization on prolonged exposure to agonist, complicating structural investigations of the transient open conformation. <ref>PMID:18987633</ref> The overall architecture of bacterial Gloeobacter violaceus pentameric ligand-gated ion(GLIC) is similar to nAChR(Fig 1). | X-ray structure of homologues of the extracellular domain(ECD) of nAChRs have also been described:the acetylcholine binding protein(AChBP) co-crystallized with agonists and antagonists, and the ECD of α1-nAChRs. Most pLGICs undergo desensitization on prolonged exposure to agonist, complicating structural investigations of the transient open conformation. <ref>PMID:18987633</ref> The overall architecture of bacterial Gloeobacter violaceus pentameric ligand-gated ion(GLIC) is similar to nAChR(Fig 1). The five subunits are arranged in a barrel-like manner around a central symmetry axis that coincides with the ion permeation pathway.<ref>PMID:18987633</ref> The transmembrane domain of each subunit consists of four helices and M2 helices form the wall of the pore. | ||