Premium
37 Axon guidance by diffusible attract ants and repellents
Author(s) -
Serafini Tito,
Colarmarino Sophia A.,
Galko Michael J.,
Kennedy Timothy E.,
Leonardo E. David,
Mirzayan Christine,
Torre José R.,
Wang Hao,
Beddington Rosa S.,
Jessell Thomas M.,
Skarnes William C.,
TessierLavigne Marc
Publication year - 1996
Publication title -
international journal of developmental neuroscience
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.761
H-Index - 88
eISSN - 1873-474X
pISSN - 0736-5748
DOI - 10.1016/0736-5748(96)80232-2
Subject(s) - art history , humanities , art , library science , philosophy , environmental ethics , classics , computer science
CommissuraJ sons pioneer a clrcumferenbal pathway to the floor plate at the venual midline of the spinal cord. Floor plate cells secrete a diffusible factor that attracts these axons tn VIITO. suggesting that then ventral growth IS directed by cbemotropism We have purified from embryomc chick bram two proteins. netnn -I and netrin-2. that each mimic the activity of the iloor plate Cloning of cDNAs encoding the netnns shows lhat they are vertebrate bomologues of UNC-6, a lamlmn-related protein required for the circumferenbal dorsal and ventral rmgration of cells and i~xons in the nematode C. elegant. The netnnI gene 1s expressed by floor plate cells, and beterologous cells secreung recombinant netrin1 munic the long-range cbemotropic activity of floor plate cells Moreover, axons that grow dorsally away from the floor plate are repelled by netrin-1. Thus. nelnn-1 is a bifunctional guidance cue that may serve to attract some axons LO the floor plate while steering others away Enamma(lon of the trajectories of conunissural axons in race lackmg nebin-l imhcates that netnn-1 is required in V~L’O for the growth of most commissnral axons to the floor plate. Netinis also required 1~1 ~110 for the proper development of other commissures such as the hppocampal c~mm~~urc and rhe corpus callosum Faissner, A., A. Scholze, B. G&z, A. Joester, 0. Schngdelbach, F. Wigger, K. Schiitte, and A. Clement. Department of Neurobiology, INF 364, D-69120 Heidelberg, FRG.