title: Afferent Connectivity of the Zebrafish Habenulae.
abstract: The habenulae are bilateral nuclei located in the dorsal diencephalon that are conserved across vertebrates. Here we describe the main afferents to the habenulae in larval and adult zebrafish. We observe afferents from the subpallium, nucleus rostrolateralis, posterior tuberculum, posterior hypothalamic lobe, median raphe; we also see asymmetric afferents from olfactory bulb to the right habenula, and from the parapineal to the left habenula. In addition, we find afferents from a ventrolateral telencephalic nucleus that neurochemical and hodological data identify as the ventral entopeduncular nucleus (vENT), confirming and extending observations of Amo et al. (2014). Fate map and marker studies suggest that vENT originates from the diencephalic prethalamic eminence and extends into the lateral telencephalon from 48 to 120 hour post-fertilization (hpf). No afferents to the habenula were observed from the dorsal entopeduncular nucleus (dENT). Consequently, we confirm that the vENT (and not the dENT) should be considered as the entopeduncular nucleus "proper" in zebrafish. Furthermore, comparison with data in other vertebrates suggests that the vENT is a conserved basal ganglia nucleus, being homologous to the entopeduncular nucleus of mammals (internal segment of the globus pallidus of primates) by both embryonic origin and projections, as previously suggested by Amo et al. (2014).
authors.affiliation: Department of Cell and Developmental Biology, University College London (UCL) London, UK.
authors.forename: Katherine J
authors.initials: KJ
authors.lastname: Turner
authors.affiliation: Department of Cell and Developmental Biology, University College London (UCL) London, UK.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Hawkins
authors.affiliation: Neurover Group, Centro de Investigacións Científicas Avanzadas (CICA) and Department of Cell and Molecular Biology, University of A Coruña (UDC) A Coruña, Spain.
authors.forename: Julián
authors.initials: J
authors.lastname: Yáñez
authors.affiliation: Department of Cell Biology and Ecology, Faculty of Biology, University of Santiago de Compostela Santiago de Compostela, Spain.
authors.forename: Ramón
authors.initials: R
authors.lastname: Anadón
authors.affiliation: Department of Cell and Developmental Biology, University College London (UCL) London, UK.
authors.forename: Stephen W
authors.initials: SW
authors.lastname: Wilson
authors.affiliation: Department of Cell and Developmental Biology, University College London (UCL)London, UK; Neurover Group, Centro de Investigacións Científicas Avanzadas (CICA) and Department of Cell and Molecular Biology, University of A Coruña (UDC)A Coruña, Spain.
authors.forename: Mónica
authors.initials: M
authors.lastname: Folgueira
mesh_terms: D000344:Afferent Pathways / Q000502:physiology*; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D030801:Animals, Genetically Modified; D001479:Basal Ganglia; D001931:Brain Mapping; D064032:Calbindin 2 / Q000235:genetics / Q000378:metabolism; D004625:Embryo, Nonmammalian; D007839:Functional Laterality; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology*; D018698:Glutamic Acid / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D019262:Habenula / Q000166:cytology / Q000254:growth & development / Q000502:physiology*; D007814:Larva; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D009830:Olfactory Bulb; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D000596:Amino Acids; D064032:Calbindin 2; D009419:Nerve Tissue Proteins; D029961:Zebrafish Proteins; C098463:dolaisoleucine; D049452:Green Fluorescent Proteins; D018698:Glutamic Acid
keywords: afferents; basal ganglia; connections; entopeduncular nucleus; habenula; posterior tuberculum; zebrafish