title: Regional expression and ultrastructural localization of EphA7 in the hippocampus and cerebellum of adult rat.
abstract: EphA7 is expressed in the adult central nervous system (CNS), where its roles are yet poorly defined. We mapped its distribution using in situ hybridization (ISH) and immunohistochemistry (IHC) combined with light (LM) and electron microscopy (EM) in adult rat and mouse brain. The strongest ISH signal was in the hippocampal pyramidal and granule cell layers. Moderate levels were detected in habenula, striatum, amygdala, the cingulate, piriform and entorhinal cortex, and in cerebellum, notably the Purkinje cell layer. The IHC signal distribution was consistent with ISH results, with transport of the protein to processes, as exemplified in the hippocampal neuropil layers and weakly stained pyramidal cell layers. In contrast, in the cerebellum, the Purkinje cell bodies were the most strongly immunolabeled elements. EM localized the cell surface-expression of EphA7 essentially in postsynaptic densities (PSDs) of dendritic spines and shafts, and on some astrocytic leaflets, in both hippocampus and cerebellum. Perikaryal and dendritic labeling was mostly intracellular, associated with the synthetic and trafficking machineries. Immunopositive vesicles were also observed in axons and axon terminals. Quantitative analysis in EM showed significant differences in the frequency of labeled elements between regions. Notably, labeled dendrites were ∼3-5 times less frequent in cerebellum than in hippocampus, but they were individually endowed with ∼10-40 times higher frequencies of PSDs, on their shafts and spines. The cell surface localization of EphA7, being preferentially in PSDs, and in perisynaptic astrocytic leaflets, provides morphologic evidence that EphA7 plays key roles in adult CNS synaptic maintenance, plasticity, or function. J. Comp. Neurol. 524:2462-2478, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Département de neurosciences and Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, QC, Canada.
authors.forename: Clara A
authors.initials: CA
authors.lastname: Amegandjin
authors.affiliation: Département de neurosciences and Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, QC, Canada.
authors.forename: Wafaa
authors.initials: W
authors.lastname: Jammow
authors.affiliation: Centre hospitalier de l'Université Laval (CHUL), Québec, QC, Canada.
authors.forename: Sylvie
authors.initials: S
authors.lastname: Laforest
authors.affiliation: Département de neurosciences and Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, QC, Canada.
authors.forename: Mustapha
authors.initials: M
authors.lastname: Riad
authors.affiliation: Département de neurosciences and Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, QC, Canada.
authors.forename: Moogeh
authors.initials: M
authors.lastname: Baharnoori
authors.affiliation: Département de biochimie et médecine moléculaire, Université de Montréal, Montréal, QC, Canada.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Badeaux
authors.affiliation: Département de biochimie et médecine moléculaire, Université de Montréal, Montréal, QC, Canada.
authors.forename: Luc
authors.initials: L
authors.lastname: DesGroseillers
authors.affiliation: Department of Neurology and Neurosurgery, McGill University, and Center for Research in Neuroscience, Montréal, QC, Canada.
authors.forename: Keith K
authors.initials: KK
authors.lastname: Murai
authors.affiliation: Sanford-Burnham Medical Research Institute, La Jolla, California, and Pathology Department, University of California, San Diego, La Jolla, California, USA.
authors.forename: Elena B
authors.initials: EB
authors.lastname: Pasquale
authors.affiliation: Centre hospitalier de l'Université Laval (CHUL), Québec, QC, Canada.
authors.forename: Guy
authors.initials: G
authors.lastname: Drolet
authors.affiliation: Département de neurosciences and Groupe de recherche sur le système nerveux central (GRSNC), Université de Montréal, Montréal, QC, Canada.
authors.forename: Guy
authors.initials: G
authors.lastname: Doucet
mesh_terms: D000818:Animals; D002531:Cerebellum / Q000378:metabolism* / Q000648:ultrastructure*; D003712:Dendrites / Q000378:metabolism / Q000648:ultrastructure; D015870:Gene Expression; D006624:Hippocampus / Q000378:metabolism* / Q000648:ultrastructure*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D051381:Rats; D017207:Rats, Sprague-Dawley; D036141:Receptor, EphA7 / Q000096:biosynthesis* / Q000648:ultrastructure*
chemical_list: C093291:EPHA7 protein, rat; D036141:Receptor, EphA7
keywords: Eph receptor; astrocytes; cerebellum; dendritic spines; hippocampus; ultrastructure