PT - JOURNAL ARTICLE AU - Juan de la Parra AU - María I. Cuartero AU - Alberto Pérez-Ruiz AU - Alicia García-Culebras AU - Ricardo Martín AU - José Sánchez-Prieto AU - Juan M. García-Segura AU - Ignacio Lizasoain AU - María A. Moro TI - AhR Deletion Promotes Aberrant Morphogenesis and Synaptic Activity of Adult-Generated Granule Neurons and Impairs Hippocampus-Dependent Memory AID - 10.1523/ENEURO.0370-17.2018 DP - 2018 Jul 01 TA - eneuro PG - ENEURO.0370-17.2018 VI - 5 IP - 4 4099 - http://www.eneuro.org/content/5/4/ENEURO.0370-17.2018.short 4100 - http://www.eneuro.org/content/5/4/ENEURO.0370-17.2018.full SO - eNeuro2018 Jul 01; 5 AB - Newborn granule cells are continuously produced in the subgranular zone of dentate gyrus throughout life. Once these cells mature, they integrate into pre-existing circuits modulating hippocampus-dependent memory. Subsequently, mechanisms controlling generation and maturation of newborn cells are essential for proper hippocampal function. Therefore, we have studied the role of aryl hydrocarbon receptor (AhR), a ligand-activated bHLH-PAS transcription factor, in hippocampus-dependent memory and granule neuronal morphology and function using genetic loss-of-function approaches based on constitutive and inducible-nestin AhR–/– mice. The results presented here show that the impaired hippocampus-dependent memory in AhR absence is not due to its effects on neurogenesis but to aberrant dendritic arborization and an increased spine density, albeit with a lower number of mature mushrooms spines in newborn granule cells, a finding that is associated with an immature electrophysiological phenotype. Together, our data strongly suggest that AhR plays a pivotal role in the regulation of hippocampal function, by controlling hippocampal granule neuron morphology and synaptic maturation.