title: Epidermis-Derived Semaphorin Promotes Dendrite Self-Avoidance by Regulating Dendrite-Substrate Adhesion in Drosophila Sensory Neurons.
abstract: Precise patterning of dendritic arbors is critical for the wiring and function of neural circuits. Dendrite-extracellular matrix (ECM) adhesion ensures that the dendrites of Drosophila dendritic arborization (da) sensory neurons are properly restricted in a 2D space, and thereby facilitates contact-mediated dendritic self-avoidance and tiling. However, the mechanisms regulating dendrite-ECM adhesion in vivo are poorly understood. Here, we show that mutations in the semaphorin ligand sema-2b lead to a dramatic increase in self-crossing of dendrites due to defects in dendrite-ECM adhesion, resulting in a failure to confine dendrites to a 2D plane. Furthermore, we find that Sema-2b is secreted from the epidermis and signals through the Plexin B receptor in neighboring neurons. Importantly, we find that Sema-2b/PlexB genetically and physically interacts with TORC2 complex, Tricornered (Trc) kinase, and integrins. These results reveal a novel role for semaphorins in dendrite patterning and illustrate how epidermal-derived cues regulate neural circuit assembly.
authors: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
authors: Shan
authors: S
authors: Meltzer
authors: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
authors: Smita
authors: S
authors: Yadav
authors: Department of Biology, University of Washington, Seattle, WA 98195, USA.
authors: Jiae
authors: J
authors: Lee
authors: Center for Molecular Neurobiology (ZMNH), University of Hamburg Medical School, Falkenried 94, 20251 Hamburg, Germany.
authors: Peter
authors: P
authors: Soba
authors: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
authors: Susan H
authors: SH
authors: Younger
authors: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
authors: Peng
authors: P
authors: Jin
authors: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
authors: Wei
authors: W
authors: Zhang
authors: Department of Biology, University of Washington, Seattle, WA 98195, USA.
authors: Jay
authors: J
authors: Parrish
authors: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA.
authors: Lily Yeh
authors: LY
authors: Jan
authors: Howard Hughes Medical Institute, Departments of Physiology, Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94158, USA. Electronic address: yuhnung.jan@ucsf.edu.
authors: Yuh-Nung
authors: YN
authors: Jan
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002450:Cell Communication; D003712:Dendrites / Q000502:physiology*; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004817:Epidermis / Q000502:physiology*; D051417:Focal Adhesion Kinase 1 / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D047468:Immunoprecipitation; D007814:Larva; D000076225:Mechanistic Target of Rapamycin Complex 2; D008967:Molecular Biology; D046912:Multiprotein Complexes / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D039961:Semaphorins / Q000235:genetics / Q000378:metabolism*; D011984:Sensory Receptor Cells / Q000166:cytology*; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism; D014162:Transfection
chemical_list: D029721:Drosophila Proteins; D046912:Multiprotein Complexes; D009419:Nerve Tissue Proteins; D011956:Receptors, Cell Surface; D039961:Semaphorins; C116484:plexB protein, Drosophila; D049452:Green Fluorescent Proteins; C496049:Fak protein, Drosophila; D051417:Focal Adhesion Kinase 1; D000076225:Mechanistic Target of Rapamycin Complex 2; D058570:TOR Serine-Threonine Kinases