Abstract
Netrins are bifunctional guidance molecules, attracting some axons and repelling others. They act through receptors of the DCC and UNC5 families. DCC receptors have been implicated in both attraction and repulsion by Netrins. UNC5 receptors are required only for repulsion. In Drosophila, Netrins are expressed by midline cells of the CNS and by specific muscles in the periphery. They attract commissural and motor axons expressing the DCC family receptor Frazzled. Here we report the identification of the Drosophila Unc5 receptor, and show that it is a repulsive Netrin receptor likely to contribute to motor axon guidance. Ectopic expression of Unc5 on CNS axons can elicit either short- or long-range repulsion from the midline. Both short- and long-range repulsion require Netrin function, but only long-range repulsion requires Frazzled.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Amino Acid Sequence
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Animals
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Animals, Genetically Modified
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Axons / physiology*
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Caenorhabditis elegans Proteins*
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Drosophila
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Drosophila Proteins / genetics*
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Drosophila Proteins / metabolism*
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Gene Expression Regulation, Developmental
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Growth Cones / physiology
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Helminth Proteins / genetics
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Interneurons / physiology
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Interneurons / ultrastructure
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Membrane Proteins / genetics
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Molecular Sequence Data
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Motor Neurons / physiology
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Motor Neurons / ultrastructure
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Netrin Receptors
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Receptors, Cell Surface / genetics*
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Receptors, Cell Surface / metabolism*
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Receptors, Growth Factor / genetics
Substances
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Caenorhabditis elegans Proteins
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Drosophila Proteins
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Helminth Proteins
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Membrane Proteins
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Netrin Receptors
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Receptors, Cell Surface
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Receptors, Growth Factor
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fra protein, Drosophila
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unc-5 protein, Drosophila
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UNC-5 protein, C elegans