Neural development requires the generation of a remarkable diversity of neural cell types and the stereotyped and often highly ordered specification of synaptic connections between these cells. A large number of studies have demonstrated that receptor-configured protein-tyrosine kinases (PTKs) play central roles in both of these events. Recent work from our laboratory and others has provided strong circumstantial evidence that several members of what is the largest sub-family of receptor PTKs in vertebrates-the Eph receptors-function to pattern topographic axonal projects that map ordered synaptic activity in one set of neurons onto another. Perhaps the best studied of such maps connects the retinal ganglion cells of the eye to their targets in the superior colliculus (SC) of the midbrain. In this map, a gradient of EphA receptors in the retina is hypothesized to interact with a complementary gradient of axon-repellant ephrin-A ligands in the SC. We propose to experimentally manipulate and analyze a batter of recently generated mouse lines that carry both loss-of-function and gain-of-functions mutations in the genes encoding many of these receptors and ligands, and to thereby assess in vivo the validity of previously advanced but largely untested hypotheses as to the mechanism of action of the EphA signaling system. We will also use these same mouse mutants to experimentally assess the functional relevance of this signaling system to the specificity of synaptic innervation from motor neurons in the spinal cord to their muscle targets in the limbs and the body wall.

Project Start
1993-01-01
Project End
2006-03-31
Budget Start
Budget End
Support Year
9
Fiscal Year
2001
Total Cost
$197,422
Indirect Cost
Name
Salk Institute for Biological Studies
Department
Type
DUNS #
005436803
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Zhang, Jingming; Lanuza, Guillermo M; Britz, Olivier et al. (2014) V1 and v2b interneurons secure the alternating flexor-extensor motor activity mice require for limbed locomotion. Neuron 82:138-50
Borowska, Joanna; Jones, Christopher T; Zhang, Han et al. (2013) Functional subpopulations of V3 interneurons in the mature mouse spinal cord. J Neurosci 33:18553-65
Levine, Ariel J; Lewallen, Kathryn A; Pfaff, Samuel L (2012) Spatial organization of cortical and spinal neurons controlling motor behavior. Curr Opin Neurobiol 22:812-21
Bonanomi, Dario; Chivatakarn, Onanong; Bai, Ge et al. (2012) Ret is a multifunctional coreceptor that integrates diffusible- and contact-axon guidance signals. Cell 148:568-82
Wang, Biao; Moya, Noel; Niessen, Sherry et al. (2011) A hormone-dependent module regulating energy balance. Cell 145:596-606
Bevins, Nicholas; Lemke, Greg; Reber, Michael (2011) Genetic dissection of EphA receptor signaling dynamics during retinotopic mapping. J Neurosci 31:10302-10
Alaynick, William A; Jessell, Thomas M; Pfaff, Samuel L (2011) SnapShot: spinal cord development. Cell 146:178-178.e1
Bai, Ge; Chivatakarn, Onanong; Bonanomi, Dario et al. (2011) Presenilin-dependent receptor processing is required for axon guidance. Cell 144:106-18
Garcia-Campmany, Lidia; Stam, Floor J; Goulding, Martyn (2010) From circuits to behaviour: motor networks in vertebrates. Curr Opin Neurobiol 20:116-25
Grossmann, Katja S; Giraudin, Aurore; Britz, Olivier et al. (2010) Genetic dissection of rhythmic motor networks in mice. Prog Brain Res 187:19-37

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