title: Changes of phospho-growth-associated protein 43 (phospho-GAP43) in the zebrafish retina after optic nerve injury: a long-term observation.
abstract: The major model animal of optic nerve regeneration in fish is goldfish. A closely related zebrafish is the most popular model system for genetic and developmental studies of vertebrate central nervous system. A few challenging works of optic nerve regeneration have been done with zebrafish. However, knowledge concerning the long term of optic nerve regeneration apparently lacks in zebrafish. In the present study, therefore, we followed changes of zebrafish behavior and phosphorylated form of growth-associated protein 43 (phospho-GAP43) expression in the zebrafish retina over 100 days after optic nerve transection. Optomotor response was fast recovered by 20-25 days after axotomy whereas chasing behavior (a schooling behavior) was slowly recovered by 80-100 days after axotomy. The temporal pattern of phospho-GAP43 expression showed a biphasic increase, a short-peak (12 folds) at 1-2 weeks and a long-plateau (4 folds) at 1-2 months after axotomy. The recovery of optomotor response well correlated with projection of growing axons to the tectum, whereas the recovery of chasing behavior well correlated with synaptic refinement of retinotectal topography. The present data strongly suggest that phospho-GAP43 plays an active role in both the early and late stages of optic nerve regeneration in fish.
authors.affiliation: Department of Molecular Neurobiology, Graduate School of Medicine, Kanazawa University, 13-1 Takara-machi, Kanazawa, Ishikawa 920-8640, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Kaneda
authors.forename: Mikiko
authors.initials: M
authors.lastname: Nagashima
authors.forename: Tomoya
authors.initials: T
authors.lastname: Nunome
authors.forename: Takanori
authors.initials: T
authors.lastname: Muramatsu
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Yamada
authors.forename: Mamoru
authors.initials: M
authors.lastname: Kubo
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Muramoto
authors.forename: Toru
authors.initials: T
authors.lastname: Matsukawa
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Koriyama
authors.forename: Kayo
authors.initials: K
authors.lastname: Sugitani
authors.forename: Ivan H
authors.initials: IH
authors.lastname: Vachkov
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Mawatari
authors.forename: Satoru
authors.initials: S
authors.lastname: Kato
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D019771:Axotomy / Q000379:methods; D001522:Behavior, Animal; D019922:GAP-43 Protein / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000502:physiology*; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D009416:Nerve Regeneration / Q000502:physiology; D020221:Optic Nerve Injuries / Q000378:metabolism / Q000473:pathology*; D012333:RNA, Messenger / Q000378:metabolism; D012160:Retina / Q000378:metabolism*; D013997:Time Factors; D014795:Visual Pathways / Q000378:metabolism / Q000473:pathology; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate / Q000378:metabolism; D015027:Zebrafish / Q000378:metabolism; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D019922:GAP-43 Protein; D005904:Glial Fibrillary Acidic Protein; D012333:RNA, Messenger; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D029961:Zebrafish Proteins