Structural insights into opposing actions of neurosteroids on GABAA receptors
Journal Article
·
· Nature Communications
- UT Southwestern Medical Center, Dallas, TX (United States)
- Stockholm University, Solna (Sweden)
- University of California San Diego, La Jolla, CA (United States)
- Stockholm University, Solna (Sweden); KTH Royal Institute of Technology, Solna (Sweden)
- UT Southwestern Medical Center, Dallas, TX (United States); University of California San Diego, La Jolla, CA (United States)
γ-Aminobutyric acid type A (GABAA) receptors mediate fast inhibitory signaling in the brain and are targets of numerous drugs and endogenous neurosteroids. A subset of neurosteroids are GABAA receptor positive allosteric modulators; one of these, allopregnanolone, is the only drug approved specifically for treating postpartum depression. There is a consensus emerging from structural, physiological and photolabeling studies as to where positive modulators bind, but how they potentiate GABA activation remains unclear. Other neurosteroids are negative modulators of GABAA receptors, but their binding sites remain debated. Here we present structures of a synaptic GABAA receptor bound to allopregnanolone and two inhibitory sulfated neurosteroids. Allopregnanolone binds at the receptor-bilayer interface, in the consensus potentiator site. In contrast, inhibitory neurosteroids bind in the pore. MD simulations and electrophysiology support a mechanism by which allopregnanolone potentiates channel activity and suggest the dominant mechanism for sulfated neurosteroid inhibition is through pore block.
- Research Organization:
- Pacific Northwest National Laboratory (PNNL), Richland, WA (United States). Environmental Molecular Sciences Laboratory (EMSL)
- Sponsoring Organization:
- CPRIT Core Facility Support Award; National Institutes of Health (NIH); Stockholm University; Swedish Research Council; USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); USDOE Office of Science (SC), Biological and Environmental Research (BER); Welch Foundation
- Grant/Contract Number:
- AC05-76RL01830
- OSTI ID:
- 2424192
- Journal Information:
- Nature Communications, Journal Name: Nature Communications Journal Issue: 1 Vol. 14; ISSN 2041-1723
- Publisher:
- Nature Publishing GroupCopyright Statement
- Country of Publication:
- United States
- Language:
- English
Similar Records
Cryo-EM structures reveal native GABAA receptor assemblies and pharmacology
Structural and dynamic mechanisms of GABAA receptor modulators with opposing activities
Structural basis of neurosteroid anesthetic action on GABAA receptors
Journal Article
·
Tue Sep 19 20:00:00 EDT 2023
· Nature (London)
·
OSTI ID:2471665
Structural and dynamic mechanisms of GABAA receptor modulators with opposing activities
Journal Article
·
Fri Aug 05 20:00:00 EDT 2022
· Nature Communications
·
OSTI ID:1903929
Structural basis of neurosteroid anesthetic action on GABAA receptors
Journal Article
·
Thu Sep 27 20:00:00 EDT 2018
· Nature Communications
·
OSTI ID:1529559