PMID- 24096136 OWN - NLM STAT- MEDLINE DCOM- 20140814 LR - 20211021 IS - 1873-7544 (Electronic) IS - 0306-4522 (Print) IS - 0306-4522 (Linking) VI - 255 DP - 2013 TI - Gephyrin plays a key role in BDNF-dependent regulation of amygdala surface GABAARs. PG - 33-44 LID - S0306-4522(13)00830-0 [pii] LID - 10.1016/j.neuroscience.2013.09.051 [doi] AB - Brain-derived neurotrophic factor (BDNF) is critically involved in synaptic plasticity and neurotransmission. Our lab has previously found that BDNF activation of neurotrophic tyrosine kinase, receptor, type 2 (TrkB) is required for fear memory formation and that GABAA receptor (GABAAR) subunits and the GABAA clustering protein gephyrin are dynamically regulated during fear memory consolidation. We hypothesize that TrkB-dependent internalization of GABAARs may partially underlie a transient period of amygdala hyperactivation during fear memory consolidation. We have previously reported that BDNF modulates GABAAR alpha1 subunit sequestration in cultured hippocampal and amygdala neurons by differential phosphorylation pathways. At present, no studies have investigated the regulation of gephyrin and GABAAR alpha1 subunits following BDNF activation in the amygdala. In this study, we confirm the association of GABAAR alpha1 and gamma2 subunits with gephyrin on mouse amygdala neurons by coimmunoprecipitation and immunocytochemistry. We then demonstrate that rapid BDNF treatment, as well as suppression of gephyrin protein levels on amygdala neurons, induced sequestration of surface alpha1 subunits. Further, we find that rapid exposure of BDNF to primary amygdala cultures produced decreases in gephyrin levels, whereas longer exposure resulted in an eventual increase. While total alpha1 subunit levels remained unchanged, gephyrin was downregulated in whole cell homogenates, but enhanced in complexes with GABAARs. Our data with anisomycin suggest that BDNF may rapidly induce gephyrin protein degradation, with subsequent gephyrin synthesis occurring. Together, these findings suggest that gephyrin may be a key factor in BDNF-dependent GABAAR regulation in the amygdala. This work may inform future studies aimed at elucidating the pathways connecting BDNF, GABAA systems, gephyrin, and their role in underlying amygdala-dependent learning. CI - Copyright (c) 2013 IBRO. Published by Elsevier Ltd. All rights reserved. FAU - Mou, L AU - Mou L AD - Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA; Howard Hughes Medical Institute, Chevy Chase, MD, USA. FAU - Dias, B G AU - Dias BG FAU - Gosnell, H AU - Gosnell H FAU - Ressler, K J AU - Ressler KJ LA - eng GR - R01 MH096764/MH/NIMH NIH HHS/United States GR - P51 RR000165/RR/NCRR NIH HHS/United States GR - P51RR000165/RR/NCRR NIH HHS/United States GR - MH096764/MH/NIMH NIH HHS/United States GR - DA019624/DA/NIDA NIH HHS/United States GR - R01 DA019624/DA/NIDA NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural DEP - 20131003 PL - United States TA - Neuroscience JT - Neuroscience JID - 7605074 RN - 0 (Brain-Derived Neurotrophic Factor) RN - 0 (Carrier Proteins) RN - 0 (Membrane Proteins) RN - 0 (Receptors, GABA-A) RN - 0 (gephyrin) SB - IM MH - Amygdala/*metabolism MH - Animals MH - Blotting, Western MH - Brain-Derived Neurotrophic Factor/*metabolism MH - Carrier Proteins/*metabolism MH - Gene Expression Regulation/physiology MH - Humans MH - Immunohistochemistry MH - Immunoprecipitation MH - Membrane Proteins/*metabolism MH - Mice MH - Mice, Inbred C57BL MH - Neurons/metabolism MH - Receptors, GABA-A/*metabolism MH - Transfection PMC - PMC3910431 MID - NIHMS548230 OTO - NOTNLM OT - BDNF OT - GABA OT - GABA(A) receptors OT - GABA(A)Rs OT - GFP OT - ICC OT - IP OT - PBS OT - SDS-PAGE OT - TrkB OT - amygdala OT - brain-derived neurotrophic factor OT - consolidation OT - fear OT - gephyrin OT - green fluorescent protein OT - immunocytochemistry OT - immunoprecipitation OT - memory OT - neurotrophic tyrosine kinase, receptor, type 2 OT - phosphate-buffered saline OT - sodium dodecyl sulfate polyacrylamide gel electrophoresis COIS- Disclosures: The authors have no financial or other potential conflictual relationships to disclose related to the work described in this manuscript. EDAT- 2013/10/08 06:00 MHDA- 2014/08/15 06:00 PMCR- 2014/06/26 CRDT- 2013/10/08 06:00 PHST- 2013/04/25 00:00 [received] PHST- 2013/09/18 00:00 [revised] PHST- 2013/09/23 00:00 [accepted] PHST- 2013/10/08 06:00 [entrez] PHST- 2013/10/08 06:00 [pubmed] PHST- 2014/08/15 06:00 [medline] PHST- 2014/06/26 00:00 [pmc-release] AID - S0306-4522(13)00830-0 [pii] AID - 10.1016/j.neuroscience.2013.09.051 [doi] PST - ppublish SO - Neuroscience. 2013;255:33-44. doi: 10.1016/j.neuroscience.2013.09.051. Epub 2013 Oct 3.