Dataset Information

Brain region differences in α1 and α5 subunit-containing GABAA receptor proteome revealed by affinity purification and Blue Native PAGE proteomics

ABSTRACT: GABAA receptors are the major inhibitory receptors in the brain. They are hetero-pentamers with a composition of predominantly two α, two β and one γ or δ subunit. From the six α subunit genes, the α5 subunit displays a limited spatial expression pattern and is known to mediate both phasic and tonic inhibition. In this study, using immunoaffinity-based proteomics we identified the α5 subunit containing receptor complexes in hippocampus and olfactory bulb. The α1-α5 interaction was identified in both brain regions albeit with significantly different stoichiometries. In line with this, reverse IPs using anti-α1 antibody showed the α5-α1 co-occurrence and validated the quantitative difference. In addition, we showed that the association of Neuroligin 2 with α1-containing receptors was much higher in olfactory bulb than hippocampus, which was confirmed using blue native gel electrophoresis and quantitative mass spectrometry. Finally, immunocytochemical staining revealed co-localization of α1 and α5 subunits in post-synaptic puncta in the hippocampus.

INSTRUMENT(S): timsTOF Pro 2

ORGANISM(S): Mus Musculus (mouse)

TISSUE(S): Brain

SUBMITTER: Miao Chen

LAB HEAD: Kawan Li

PROVIDER: PXD047550 | Pride | 2024-01-26

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	20220304_miao_HcalOf-IP-alfa1-6-lipo-nlgn_spd30_DIA_HC_GRIA2_1_S1-B3_1_2837.d.zip	Other
	20220304_miao_HcalOf-IP-alfa1-6-lipo-nlgn_spd30_DIA_HC_Lipo_1_S1-B5_1_2839.d.zip	Other
	20220304_miao_HcalOf-IP-alfa1-6-lipo-nlgn_spd30_DIA_HC_Lipo_2_S1-B6_1_2840.d.zip	Other
	20220304_miao_HcalOf-IP-alfa1-6-lipo-nlgn_spd30_DIA_HC_Lipo_3_S1-B7_1_2841.d.zip	Other
	20220304_miao_HcalOf-IP-alfa1-6-lipo-nlgn_spd30_DIA_HC_Nlgn2_1_S1-B11_1_2845.d.zip	Other

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Publications

Brain Region Differences in α1- and α5-Subunit-Containing GABA<sub>A</sub> Receptor Proteomes Revealed with Affinity Purification and Blue Native PAGE Proteomics.

Chen Miao M Koopmans Frank F Gonzalez-Lozano Miguel A MA Smit August B AB Li Ka Wan KW

Cells 20231220 1

GABA<sub>A</sub> receptors are the major inhibitory receptors in the brain. They are hetero-pentamers with a composition of predominantly two α, two β, and one γ or δ subunit. Of the six α subunit genes, the α5 subunit displays a limited spatial expression pattern and is known to mediate both phasic and tonic inhibition. In this study, using immunoaffinity-based proteomics, we identified the α5 subunit containing receptor complexes in the hippocampus and olfactory bulb. The α1-α5 interaction was ...[more]

PMID: 38201218

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