title: A novel monoclonal antibody recognizes a previously unknown subdivision of the habenulo-interpeduncular system in zebrafish.
abstract: The habenulo-interpeduncular system is an evolutionarily conserved structure found in the brain of almost all vertebrates. We prepared a monoclonal antibody (6G11) which very specifically recognizes only a part of this system. 6G11 is a monoclonal antibody prepared from a neuronal membrane protein in adult zebrafish brain. In western blot analysis of the adult zebrafish brain, the antibody recognized a 95 kDa protein, and the class of the antibody was determined to be IgM. The 6G11 antigen was not detected in zebrafish muscle, intestine, testis or ovary. A group of neurons stained by the 6G11 antibody was located in the caudomedial part of the zebrafish habenula. The 6G11-immunopositive neurons extended their axons into the fasciculus retroflexus (FR). One group of immunopositive neurons projected toward the interpeduncular nucleus (IPN), especially to the intermediate and the central subnucleus (type 1 neuron). The other group projected to the ventral midline at the level of the raphe nucleus; these axons passed ipsilaterally beside the IPN and converged in the ventral midline under the raphe nucleus (type 2 neuron). Both type 1 and type 2 fibers are relatively minor components of the FR. Little has previously been known about this topological pattern in any species. The 6G11 monoclonal antibody could be a useful tool for expanding knowledge of the habenulo-interpeduncular system.
authors.affiliation: Department of Biology, Faculty of Science, Okayama University, 700-8530, Okayama, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Tomizawa
authors.forename: H
authors.initials: H
authors.lastname: Katayama
authors.forename: H
authors.initials: H
authors.lastname: Nakayasu
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000302:isolation & purification / Q000494:pharmacology*; D000918:Antibody Specificity; D000954:Antigens, Surface / Q000276:immunology / Q000378:metabolism; D001369:Axons / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D002232:Carbocyanines / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism; D005456:Fluorescent Dyes / Q000494:pharmacology; D019262:Habenula / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D008636:Mesencephalon / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000276:immunology / Q000378:metabolism; D009434:Neural Pathways / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D011903:Raphe Nuclei / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D013347:Subcellular Fractions; D015027:Zebrafish / Q000033:anatomy & histology / Q000276:immunology / Q000378:metabolism*
chemical_list: C035005:3,3'-dihexadecylindocarbocyanine; D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D002232:Carbocyanines; D005456:Fluorescent Dyes; D009419:Nerve Tissue Proteins