title: Adult-born neurons modify excitatory synaptic transmission to existing neurons.
abstract: Adult-born neurons are continually produced in the dentate gyrus but it is unclear whether synaptic integration of new neurons affects the pre-existing circuit. Here we investigated how manipulating neurogenesis in adult mice alters excitatory synaptic transmission to mature dentate neurons. Enhancing neurogenesis by conditional deletion of the pro-apoptotic geneBaxin stem cells reduced excitatory postsynaptic currents (EPSCs) and spine density in mature neurons, whereas genetic ablation of neurogenesis increased EPSCs in mature neurons. Unexpectedly, we found thatBaxdeletion in developing and mature dentate neurons increased EPSCs and prevented neurogenesis-induced synaptic suppression. Together these results show that neurogenesis modifies synaptic transmission to mature neurons in a manner consistent with a redistribution of pre-existing synapses to newly integrating neurons and that a non-apoptotic function of the Bax signaling pathway contributes to ongoing synaptic refinement within the dentate circuit.
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Elena W
authors.initials: EW
authors.lastname: Adlaf
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Vaden
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Anastasia J
authors.initials: AJ
authors.lastname: Niver
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Allison F
authors.initials: AF
authors.lastname: Manuel
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Vincent C
authors.initials: VC
authors.lastname: Onyilo
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Matheus T
authors.initials: MT
authors.lastname: Araujo
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Cristina V
authors.initials: CV
authors.lastname: Dieni
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Hai T
authors.initials: HT
authors.lastname: Vo
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Gwendalyn D
authors.identifier: http://orcid.org/0000-0002-3659-9241
authors.initials: GD
authors.lastname: King
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Jacques I
authors.identifier: http://orcid.org/0000-0001-8180-2061
authors.initials: JI
authors.lastname: Wadiche
authors.affiliation: Department of Neurobiology, University of Alabama at Birmingham, Birmingham, United States.
authors.forename: Linda
authors.identifier: http://orcid.org/0000-0001-7367-5998
authors.initials: L
authors.lastname: Overstreet-Wadiche
mesh_terms: D000818:Animals; D018891:Dentate Gyrus / Q000502:physiology*; D019706:Excitatory Postsynaptic Potentials; D051379:Mice; D009415:Nerve Net / Q000502:physiology*; D055495:Neurogenesis; D009474:Neurons / Q000502:physiology*; D009435:Synaptic Transmission
keywords: EPSC; adult neurogenesis; competition; dentate gyrus; developmental biology; granule cells; mouse; neuroscience; stem cells; synaptic transmission