Bestrophin 1 (BEST1) is chloride channel expressed in the eye, central nervous system (CNS), and other tissues in the body. A link between BEST1 and the principal inhibitory neurotransmitter γ-aminobutyric acid (GABA) has been proposed. The most appreciated receptors for extracellular GABA are the GABA G-protein coupled receptors and the pentameric GABA chloride channels, both of which have fundamental roles in the CNS. Here, we demonstrate that BEST1 is directly activated by GABA. Through functional studies and atomic-resolution structures of human and chicken BEST1, we identify a GABA binding site on the channel's extracellular side and determine the mechanism by which GABA binding induces opening of the channel's central gate. This same gate is activated by intracellular [Ca], indicating that BEST1 is controlled by ligands from both sides of the membrane. The studies demonstrate that BEST1, which shares no structural homology with GABA, is a GABA-activated chloride channel. The physiological implications of this finding remain to be studied.
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http://dx.doi.org/10.1101/2024.11.22.624909 | DOI Listing |
Neurochem Res
January 2025
Laboratory of Chinese Medicine Brain Science, Innovative Institute of Chinese Medicine and Pharmacy, Shandong University of Traditional Chinese Medicine, Jinan, 250355, China.
Maintaining GABAergic inhibition within physiological limits in the medial prefrontal cortex (mPFC) is critical for working memory. While synaptic GABAR typically mediate the primary component of mPFC inhibition, the role of extrasynaptic δ-GABAR in working memory remains unclear. To investigate this, we used fiber photometry to examine the effects of δ-GABAR in freely moving mice.
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School of Pharmacy, Nantong University, Nantong, Jiangsu, China.
Aims: N-Demethylsinomenine (NDSM) demonstrates good analgesic efficacy in preclinical pain models. However, how NDSM exerts analgesic actions remains unknown.
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Int J Biol Sci
January 2025
Faculty of Health Sciences, University of Macau, Taipa, Macau.
Ion channels play a crucial role in cardiac functions, and their activities exhibit dynamic changes during heart development. However, the precise function of ion channels in human heart development remains elusive. In this study, we utilized human embryonic stem cells (hESCs) as a model to mimic the process of human embryonic heart development.
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Institute of Pharmacology and Clinical Pharmacy, Goethe University Frankfurt, Frankfurt, Germany.
Proc Natl Acad Sci U S A
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National Key Laboratory of Space Medicine, China Astronaut Research and Training Center, Beijing 100094, China.
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