Show Notes
Sun C et al., PNAS - Using cryo-EM and mass spectrometry in rat cerebellum, α1- and α6-containing GABAA receptor assemblies (β‑α‑β‑α‑γ stoichiometry) and PZ-II-029 binding were defined.
Study Highlights:
The study used rat cerebellum tissue and combined confocal immunofluorescence, affinity purification with mass spectrometry, and high-resolution cryo-EM to characterize native α1-containing GABAA receptors. Cryo-EM classification resolved eight distinct α1-containing receptor assemblies that conform to a conserved β-α-β-α-γ arrangement and include previously unreported α6-containing heteromers. Structural models of α6-containing receptors show near-symmetric ECD architecture with conserved GABA-binding geometry and distinct electrostatic differences that may affect ligand kinetics. Binding of the α6-selective pyrazoloquinolinone PZ-II-029 at α+/γ− pockets was visualized and found to induce coordinated outward expansion of the extracellular domain, providing a structural basis for subtype-selective modulation.
Conclusion:
Native α1-containing cerebellar GABAA receptors adopt a conserved β-α-β-α-γ pentameric scaffold that includes α6 subunits and binds PZ-II-029 at α+/γ− sites, producing extracellular domain expansion.
Music:
Enjoy the music based on this article at the end of the episode.
Reference:
Sun C, Jahncke JN, Wright KM, Gouaux E. Molecular assemblies and pharmacology of cerebellar GABAA receptors. Proc. Natl. Acad. Sci. U.S.A. 2026;123:e2524504123. Published February 6, 2026. https://doi.org/10.1073/pnas.2524504123
License:
This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) - https://creativecommons.org/licenses/by/4.0/
Support:
Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00
Official website https://basebybase.com
On PaperCast Base by Base you’ll discover the latest in genomics, functional genomics, structural genomics, and proteomics.
Episode link: https://basebybase.castos.com/episodes/cerebellar-gabaa-alpha6-assemblies