title: Assigning the positional identity of spinal motor neurons: rostrocaudal patterning of Hox-c expression by FGFs, Gdf11, and retinoids.
abstract: Subclasses of motor neurons are generated at different positions along the rostrocaudal axis of the spinal cord. One feature of the rostrocaudal organization of spinal motor neurons is a position-dependent expression of Hox genes, but little is known about how this aspect of motor neuron subtype identity is assigned. We have used the expression profile of Hox-c proteins to define the source and identity of patterning signals that impose motor neuron positional identity along the rostrocaudal axis of the spinal cord. We provide evidence that the convergent activities of FGFs, Gdf11, and retinoid signals originating from Hensen's node and paraxial mesoderm establish and refine the Hox-c positional identity of motor neurons in the developing spinal cord.
authors.affiliation: Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biophysics, Columbia University, 701 West 168th Street, New York, NY 10032, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Liu
authors.forename: E
authors.initials: E
authors.lastname: Laufer
authors.forename: T M
authors.initials: TM
authors.lastname: Jessell
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D019521:Body Patterning / Q000502:physiology; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology*; D002478:Cells, Cultured; D002642:Chick Embryo; D016222:Fibroblast Growth Factor 2 / Q000494:pharmacology*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000502:physiology; D055412:Growth Differentiation Factors; D006168:Guinea Pigs; D018398:Homeodomain Proteins / Q000235:genetics*; D008648:Mesoderm / Q000502:physiology; D051379:Mice; D008969:Molecular Sequence Data; D009046:Motor Neurons / Q000166:cytology / Q000502:physiology*; D020897:Organizers, Embryonic / Q000502:physiology; D051381:Rats; D015398:Signal Transduction / Q000502:physiology; D013116:Spinal Cord / Q000166:cytology* / Q000196:embryology; D014212:Tretinoin / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D019485:Bone Morphogenetic Proteins; C119153:Gdf11 protein, mouse; C492267:Gdf11 protein, rat; D055412:Growth Differentiation Factors; D018398:Homeodomain Proteins; D016222:Fibroblast Growth Factor 2; D014212:Tretinoin