|Title||Netrin-1 is required for commissural axon guidance in the developing vertebrate nervous system.|
|Publication Type||Journal Article|
|Year of Publication||1996|
|Authors||Serafini T, Colamarino SA, Leonardo ED, Wang H, Beddington R, Skarnes WC, Tessier-Lavigne M|
|Date Published||1996 Dec 13|
|Keywords||Alleles, Animals, Axons, Blotting, Southern, Gene Expression Regulation, Developmental, Homozygote, Immunohistochemistry, Mice, Mice, Mutant Strains, Motor Neurons, Mutation, Nerve Growth Factors, Pons, Spinal Cord, Trochlear Nerve, Tumor Suppressor Proteins, Vertebrates|
During nervous system development, spinal commissural axons project toward floor plate cells and trochlear motor axons extend away from these cells. Netrin-1, a diffusible protein made by floor plate cells, can attract spinal commissural axons and repel trochlear axons in vitro, but its role in vivo is unknown. Netrin-1 deficient mice exhibit defects in spinal commissural axon projections that are consistent with netrin-1 guiding these axons. Defects in several forebrain commissures are also observed, suggesting additional guidance roles for netrin-1. Trochlear axon projections are largely normal, predicting the existence of additional cues for these axons, and evidence is provided for a distinct trochlear axon chemorepellent produced by floor plate cells. These results establish netrin-1 as a guidance cue that likely collaborates with other diffusible cues to guide axons in vivo.