NMDA receptors mediate synaptic competition in culture.

Activity through NMDA type glutamate receptors sculpts connectivity in the developing nervous system. This topic is typically studied in the visual system in vivo, where activity of inputs can be differentially regulated, but in which individual synapses are difficult to visualize and mechanisms gov...

Full description

Bibliographic Details
Main Authors: Kevin She, Ann Marie Craig
Format: Article
Language:English
Published: Public Library of Science (PLoS) 2011-01-01
Series:PLoS ONE
Online Access:http://europepmc.org/articles/PMC3174173?pdf=render
_version_ 1818997089129988096
author Kevin She
Ann Marie Craig
author_facet Kevin She
Ann Marie Craig
author_sort Kevin She
collection DOAJ
description Activity through NMDA type glutamate receptors sculpts connectivity in the developing nervous system. This topic is typically studied in the visual system in vivo, where activity of inputs can be differentially regulated, but in which individual synapses are difficult to visualize and mechanisms governing synaptic competition can be difficult to ascertain. Here, we develop a model of NMDA-receptor dependent synaptic competition in dissociated cultured hippocampal neurons.GluN1 -/- (KO) mouse hippocampal neurons lacking the essential NMDA receptor subunit were cultured alone or cultured in defined ratios with wild type (WT) neurons. The absence of functional NMDA receptors did not alter neuron survival. Synapse development was assessed by immunofluorescence for postsynaptic PSD-95 family scaffold and apposed presynaptic vesicular glutamate transporter VGlut1. Synapse density was specifically enhanced onto minority wild type neurons co-cultured with a majority of GluN1 -/- neighbour neurons, both relative to the GluN1 -/- neighbours and relative to sister pure wild type cultures. This form of synaptic competition was dependent on NMDA receptor activity and not conferred by the mere physical presence of GluN1. In contrast to these results in 10% WT and 90% KO co-cultures, synapse density did not differ by genotype in 50% WT and 50% KO co-cultures or in 90% WT and 10% KO co-cultures.The enhanced synaptic density onto NMDA receptor-competent neurons in minority coculture with GluN1 -/- neurons represents a cell culture paradigm for studying synaptic competition. Mechanisms involved may include a retrograde 'reward' signal generated by WT neurons, although in this paradigm there was no 'punishment' signal against GluN1 -/- neurons. Cell culture assays involving such defined circuits may help uncover the rules and mechanisms of activity-dependent synaptic competition in the developing nervous system.
first_indexed 2024-12-20T21:40:05Z
format Article
id doaj.art-537ecc8b7d3740c98459f4c9c36d2218
institution Directory Open Access Journal
issn 1932-6203
language English
last_indexed 2024-12-20T21:40:05Z
publishDate 2011-01-01
publisher Public Library of Science (PLoS)
record_format Article
series PLoS ONE
spelling doaj.art-537ecc8b7d3740c98459f4c9c36d22182022-12-21T19:25:50ZengPublic Library of Science (PLoS)PLoS ONE1932-62032011-01-0169e2442310.1371/journal.pone.0024423NMDA receptors mediate synaptic competition in culture.Kevin SheAnn Marie CraigActivity through NMDA type glutamate receptors sculpts connectivity in the developing nervous system. This topic is typically studied in the visual system in vivo, where activity of inputs can be differentially regulated, but in which individual synapses are difficult to visualize and mechanisms governing synaptic competition can be difficult to ascertain. Here, we develop a model of NMDA-receptor dependent synaptic competition in dissociated cultured hippocampal neurons.GluN1 -/- (KO) mouse hippocampal neurons lacking the essential NMDA receptor subunit were cultured alone or cultured in defined ratios with wild type (WT) neurons. The absence of functional NMDA receptors did not alter neuron survival. Synapse development was assessed by immunofluorescence for postsynaptic PSD-95 family scaffold and apposed presynaptic vesicular glutamate transporter VGlut1. Synapse density was specifically enhanced onto minority wild type neurons co-cultured with a majority of GluN1 -/- neighbour neurons, both relative to the GluN1 -/- neighbours and relative to sister pure wild type cultures. This form of synaptic competition was dependent on NMDA receptor activity and not conferred by the mere physical presence of GluN1. In contrast to these results in 10% WT and 90% KO co-cultures, synapse density did not differ by genotype in 50% WT and 50% KO co-cultures or in 90% WT and 10% KO co-cultures.The enhanced synaptic density onto NMDA receptor-competent neurons in minority coculture with GluN1 -/- neurons represents a cell culture paradigm for studying synaptic competition. Mechanisms involved may include a retrograde 'reward' signal generated by WT neurons, although in this paradigm there was no 'punishment' signal against GluN1 -/- neurons. Cell culture assays involving such defined circuits may help uncover the rules and mechanisms of activity-dependent synaptic competition in the developing nervous system.http://europepmc.org/articles/PMC3174173?pdf=render
spellingShingle Kevin She
Ann Marie Craig
NMDA receptors mediate synaptic competition in culture.
PLoS ONE
title NMDA receptors mediate synaptic competition in culture.
title_full NMDA receptors mediate synaptic competition in culture.
title_fullStr NMDA receptors mediate synaptic competition in culture.
title_full_unstemmed NMDA receptors mediate synaptic competition in culture.
title_short NMDA receptors mediate synaptic competition in culture.
title_sort nmda receptors mediate synaptic competition in culture
url http://europepmc.org/articles/PMC3174173?pdf=render
work_keys_str_mv AT kevinshe nmdareceptorsmediatesynapticcompetitioninculture
AT annmariecraig nmdareceptorsmediatesynapticcompetitioninculture