title: Islet Coordinately Regulates Motor Axon Guidance and Dendrite Targeting through the Frazzled/DCC Receptor.
abstract: Motor neuron axon targeting in the periphery is correlated with the positions of motor neuron inputs in the CNS, but how these processes are coordinated to form a myotopic map remains poorly understood. We show that the LIM homeodomain factor Islet (Isl) controls targeting of both axons and dendrites in Drosophila motor neurons through regulation of the Frazzled (Fra)/DCC receptor. Isl is required for fra expression in ventrally projecting motor neurons, and isl and fra mutants have similar axon guidance defects. Single-cell labeling indicates that isl and fra are also required for dendrite targeting in a subset of motor neurons. Finally, overexpression of Fra rescues axon and dendrite targeting defects in isl mutants. These results indicate that Fra acts downstream of Isl in both the periphery and the CNS, demonstrating how a single regulatory relationship is used in multiple cellular compartments to coordinate neural circuit wiring.
authors.affiliation: Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Celine
authors.initials: C
authors.lastname: Santiago
authors.affiliation: Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. Electronic address: gbashaw@mail.med.upenn.edu.
authors.forename: Greg J
authors.initials: GJ
authors.lastname: Bashaw
mesh_terms: D000818:Animals; D000071437:Axon Guidance / Q000502:physiology*; D001369:Axons / Q000378:metabolism* / Q000502:physiology; D002490:Central Nervous System / Q000378:metabolism / Q000502:physiology; D000075389:DCC Receptor / Q000378:metabolism*; D003712:Dendrites / Q000378:metabolism* / Q000502:physiology; D004330:Drosophila / Q000378:metabolism* / Q000502:physiology; D029721:Drosophila Proteins / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D009046:Motor Neurons / Q000378:metabolism* / Q000502:physiology; D000075386:Netrin Receptors / Q000378:metabolism*; D055495:Neurogenesis / Q000502:physiology; D011956:Receptors, Cell Surface / Q000378:metabolism
chemical_list: D000075389:DCC Receptor; D029721:Drosophila Proteins; D000075386:Netrin Receptors; D011956:Receptors, Cell Surface; C000617310:fra protein, Drosophila
keywords: Frazzled/DCC; Islet; Netrin; axon guidance; dendrite morphogenesis; homeodomain; motor neurons; myotopic map; transcription factor