title: Molecularly Defined Circuitry Reveals Input-Output Segregation in Deep Layers of the Medial Entorhinal Cortex.
abstract: Deep layers of the medial entorhinal cortex are considered to relay signals from the hippocampus to other brain structures, but pathways for routing of signals to and from the deep layers are not well established. Delineating these pathways is important for a circuit level understanding of spatial cognition and memory. We find that neurons in layers 5a and 5b have distinct molecular identities, defined by the transcription factors Etv1 and Ctip2, and divergent targets, with extensive intratelencephalic projections originating in layer 5a, but not 5b. This segregation of outputs is mirrored by the organization of glutamatergic input from stellate cells in layer 2 and from the hippocampus, with both preferentially targeting layer 5b over 5a. Our results suggest a molecular and anatomical organization of input-output computations in deep layers of the MEC, reveal precise translaminar microcircuitry, and identify molecularly defined pathways for spatial signals to influence computation in deep layers.
authors.affiliation: Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, EH8 9XD, UK.
authors.forename: Gülşen
authors.initials: G
authors.lastname: Sürmeli
authors.affiliation: Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, EH8 9XD, UK.
authors.forename: Daniel Cosmin
authors.initials: DC
authors.lastname: Marcu
authors.affiliation: Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, EH8 9XD, UK.
authors.forename: Christina
authors.initials: C
authors.lastname: McClure
authors.affiliation: Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, EH8 9XD, UK.
authors.forename: Derek L F
authors.initials: DLF
authors.lastname: Garden
authors.affiliation: Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, EH8 9XD, UK.
authors.forename: Hugh
authors.initials: H
authors.lastname: Pastoll
authors.affiliation: Centre for Integrative Physiology, University of Edinburgh, Hugh Robson Building, Edinburgh, EH8 9XD, UK. Electronic address: mattnolan@ed.ac.uk.
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Nolan
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D064092:Calbindin 1 / Q000378:metabolism; D002772:Cholera Toxin / Q000378:metabolism; D018728:Entorhinal Cortex / Q000033:anatomy & histology* / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009415:Nerve Net / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D010320:Parvalbumins / Q000378:metabolism; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D064092:Calbindin 1; D002772:Cholera Toxin; D008164:Luminescent Proteins; D008565:Membrane Proteins; D010320:Parvalbumins; D012097:Repressor Proteins; C101750:Sim1 protein, mouse; C114987:wolframin protein