EphA7 receptor: Regional expression in the brain and ultrastructural localisation hippocampus of adult rats mice

EphA7 is a member of the Eph tyrosine kinase receptor family, which regulates cell adhesion and motility. EphA7 is highly conserved in vertebrates and is widely expressed during embryogenesis, particularly during the development of the central nervous system. In the adult brain, EphA7 is transcribed primarily in the hippocampus, with low levels of expression elsewhere. We have mapped its distribution in the adult rat and mouse brain using in situ hybridisation and immunohistochemistry under light and electron microscopy. Both methods show a highly consistent pattern of labelling. The strongest signal was observed in the hippocampus, with lower levels in the habenula, striatum, amygdala, cingulate, piriform and entorhinal cortices, as well as the cerebellum. At the ultrastructural level, in the hippocampus, EphA7 immunoreactivity was localised in the cytoplasm of granule cells (dentate gyrus) and pyramidal cells (CA1 and CA3). The preferential localisation of EphA7 in dendritic spines and perisynaptic astrocytic processes is consistent with its role in synaptic plasticity.