TY - JOUR
T1 - Structural principles of distinct assemblies of the human α4β2 nicotinic receptor
AU - Walsh, Richard M.
AU - Roh, Soung Hun
AU - Gharpure, Anant
AU - Morales-Perez, Claudio L.
AU - Teng, Jinfeng
AU - Hibbs, Ryan E.
N1 - Funding Information:
We thank D. Cawley at OHSU for production of monoclonal antibodies, X. Bai for EM discussion, Y. Jiang for the use of the oocyte rig, C. Noviello for assistance in EM data collection and all members of the Hibbs Laboratory and M. Horvath for discussion. Cryo-EM data were collected at the UT Southwestern Medical Center Cryo-Electron Microscopy Facility, which is funded in part by CPRIT Core Facility Support Award RP170644. We thank D. Nicastro and Z. Chen for support in facility access and data acquisition and W. Chiu for cryo-EM training and resources in the National Center for Macromolecular Imaging (NCMI) at Baylor College of Medicine. NCMI is supported by NIH Grants P41GM103832 and R01GM079429. R.M.W. acknowledges support from the Sara and Frank McKnight Fund for Biochemical Research and the NIH (T32GM008203). R.E.H. is supported by a McKnight Scholar Award, The Welch Foundation (I-1812) and the NIH (DA037492, DA042072, and NS095899)
Funding Information:
Acknowledgements We thank D. Cawley at OHSU for production of monoclonal antibodies, X. Bai for EM discussion, Y. Jiang for the use of the oocyte rig, C. Noviello for assistance in EM data collection and all members of the Hibbs Laboratory and M. Horvath for discussion. Cryo-EM data were collected at the UT Southwestern Medical Center Cryo-Electron Microscopy Facility, which is funded in part by CPRIT Core Facility Support Award RP170644. We thank D. Nicastro and Z. Chen for support in facility access and data acquisition and W. Chiu for cryo-EM training and resources in the National Center for Macromolecular Imaging (NCMI) at Baylor College of Medicine. NCMI is supported by NIH Grants P41GM103832 and R01GM079429. R.M.W. acknowledges support from the Sara and Frank McKnight Fund for Biochemical Research and the NIH (T32GM008203). R.E.H. is supported by a McKnight Scholar Award, The Welch Foundation (I-1812) and the NIH (DA037492, DA042072, and NS095899).
Publisher Copyright:
© 2018 Macmillan Publishers Ltd., part of Springer Nature.
PY - 2018/5/10
Y1 - 2018/5/10
N2 - Fast chemical communication in the nervous system is mediated by neurotransmitter-gated ion channels. The prototypical member of this class of cell surface receptors is the cation-selective nicotinic acetylcholine receptor. As with most ligand-gated ion channels, nicotinic receptors assemble as oligomers of subunits, usually as hetero-oligomers and often with variable stoichiometries 1 . This intrinsic heterogeneity in protein composition provides fine tunability in channel properties, which is essential to brain function, but frustrates structural and biophysical characterization. The α4β2 subtype of the nicotinic acetylcholine receptor is the most abundant isoform in the human brain and is the principal target in nicotine addiction. This pentameric ligand-gated ion channel assembles in two stoichiometries of α- and β-subunits (2α:3β and 3α:2β). Both assemblies are functional and have distinct biophysical properties, and an imbalance in the ratio of assemblies is linked to both nicotine addiction 2,3 and congenital epilepsy 4,5 . Here we leverage cryo-electron microscopy to obtain structures of both receptor assemblies from a single sample. Antibody fragments specific to β2 were used to 'break' symmetry during particle alignment and to obtain high-resolution reconstructions of receptors of both stoichiometries in complex with nicotine. The results reveal principles of subunit assembly and the structural basis of the distinctive biophysical and pharmacological properties of the two different stoichiometries of this receptor.
AB - Fast chemical communication in the nervous system is mediated by neurotransmitter-gated ion channels. The prototypical member of this class of cell surface receptors is the cation-selective nicotinic acetylcholine receptor. As with most ligand-gated ion channels, nicotinic receptors assemble as oligomers of subunits, usually as hetero-oligomers and often with variable stoichiometries 1 . This intrinsic heterogeneity in protein composition provides fine tunability in channel properties, which is essential to brain function, but frustrates structural and biophysical characterization. The α4β2 subtype of the nicotinic acetylcholine receptor is the most abundant isoform in the human brain and is the principal target in nicotine addiction. This pentameric ligand-gated ion channel assembles in two stoichiometries of α- and β-subunits (2α:3β and 3α:2β). Both assemblies are functional and have distinct biophysical properties, and an imbalance in the ratio of assemblies is linked to both nicotine addiction 2,3 and congenital epilepsy 4,5 . Here we leverage cryo-electron microscopy to obtain structures of both receptor assemblies from a single sample. Antibody fragments specific to β2 were used to 'break' symmetry during particle alignment and to obtain high-resolution reconstructions of receptors of both stoichiometries in complex with nicotine. The results reveal principles of subunit assembly and the structural basis of the distinctive biophysical and pharmacological properties of the two different stoichiometries of this receptor.
UR - http://www.scopus.com/inward/record.url?scp=85046693480&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85046693480&partnerID=8YFLogxK
U2 - 10.1038/s41586-018-0081-7
DO - 10.1038/s41586-018-0081-7
M3 - Article
C2 - 29720657
AN - SCOPUS:85046693480
VL - 557
SP - 261
EP - 265
JO - Nature
JF - Nature
SN - 0028-0836
IS - 7704
ER -