title: Synaptic alpha-dystrobrevin: localization of a short alpha-dystrobrevin isoform in melanin-concentrating hormone neurons of the hypothalamus.
abstract: The expression of the two members of the dystrobrevin (DB) family in the adult brain was thought to be highly specific for the two main cell types: alpha-dystrobrevin (alpha-DB) and beta-dystrobrevin (beta-DB) has been identified as glial and neuronal proteins, respectively. In the present work we show that a subset of neurons in the hypothalamus contains alpha-DB. Comparative immunohistochemical studies with two alpha-DB antibodies of different specificity indicate that the neurons contain short alpha-DB isoform(s) alpha-DB-2 and/or alpha-DB-4. Immunoreactive multipolar or spindle-shaped neurons form clusters with bilateral symmetry, localized predominantly in the lateral hypothalamic area, with extensions into the zona incerta and the dorso-medial and ventro-medial hypothalamic region. alpha-DB immunoreactivity was localized in cell processes and at postsynaptic densities, furthermore in the endoplasmic reticulum within the perikarya. alpha-DB-positive neurons are beta-dystrobrevin immunoreactive, but alpha- and beta-DB do not co-localize with their usual molecular anchors like dystrophins or high molecular weight forms of utrophin. Colocalization with nNOS was also not observed. The pattern of alpha-DB immunoreactive neurons gave a perfect colocalization with melanin-concentrating hormone (MCH) neurons throughout the whole region studied. We propose that alpha-DB plays a role in a structure or regulation mechanism unique to MCH-expressing neurons.
authors.affiliation: Faculty of Veterinary Science, Department of Anatomy and Histology, Szent István University, Budapest, Hungary.
authors.forename: Diana
authors.initials: D
authors.lastname: Hazai
authors.forename: Chun-Fu
authors.initials: CF
authors.lastname: Lien
authors.forename: Ferenc
authors.initials: F
authors.lastname: Hajós
authors.forename: Katalin
authors.initials: K
authors.lastname: Halasy
authors.forename: Dariusz C
authors.initials: DC
authors.lastname: Górecki
authors.forename: Veronika
authors.initials: V
authors.lastname: Jancsik
mesh_terms: D000818:Animals; D001931:Brain Mapping; D049029:Dystrophin-Associated Proteins / Q000737:chemistry / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D007026:Hypothalamic Area, Lateral / Q000166:cytology / Q000378:metabolism; D007028:Hypothalamic Hormones / Q000378:metabolism*; D007031:Hypothalamus / Q000166:cytology / Q000378:metabolism*; D008543:Melanins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008970:Molecular Weight; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D010907:Pituitary Hormones / Q000378:metabolism*; D020033:Protein Isoforms / Q000737:chemistry / Q000378:metabolism; D013569:Synapses / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D049029:Dystrophin-Associated Proteins; D007028:Hypothalamic Hormones; D008543:Melanins; D010907:Pituitary Hormones; D020033:Protein Isoforms; C098885:dystrobrevin; C019463:melanin-concentrating hormone