title: Dscam Proteins Direct Dendritic Targeting through Adhesion.
abstract: Cell recognition molecules are key regulators of neural circuit assembly. The Dscam family of recognition molecules in Drosophila has been shown to regulate interactions between neurons through homophilic repulsion. This is exemplified by Dscam1 and Dscam2, which together repel dendrites of lamina neurons, L1 and L2, in the visual system. By contrast, here we show that Dscam2 directs dendritic targeting of another lamina neuron, L4, through homophilic adhesion. Through live imaging and genetic mosaics to dissect interactions between specific cells, we show that Dscam2 is required in L4 and its target cells for correct dendritic targeting. In a genetic screen, we identified Dscam4 as another regulator of L4 targeting which acts with Dscam2 in the same pathway to regulate this process. This ensures tiling of the lamina neuropil through heterotypic interactions. Thus, different combinations of Dscam proteins act through distinct mechanisms in closely related neurons to pattern neural circuits.
authors: Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
authors: Wael
authors: W
authors: Tadros
authors: Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
authors: Shuwa
authors: S
authors: Xu
authors: Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
authors: Orkun
authors: O
authors: Akin
authors: Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
authors: Caroline H
authors: CH
authors: Yi
authors: School of Biomedical Sciences, The University of Queensland, Brisbane QLD 4072, Australia.
authors: Grace Ji-Eun
authors: GJ
authors: Shin
authors: School of Biomedical Sciences, The University of Queensland, Brisbane QLD 4072, Australia.
authors: S Sean
authors: SS
authors: Millard
authors: Department of Biological Chemistry, Howard Hughes Medical Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA. Electronic address: lzipursky@mednet.ucla.edu.
authors: S Lawrence
authors: SL
authors: Zipursky
mesh_terms: D000483:Alleles; D000818:Animals; D002448:Cell Adhesion / Q000235:genetics / Q000502:physiology; D003712:Dendrites / Q000502:physiology*; D029721:Drosophila Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D004331:Drosophila melanogaster; D018507:Gene Expression Regulation, Developmental / Q000502:physiology*; D009030:Mosaicism; D019006:Neural Cell Adhesion Molecules / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*
chemical_list: D029721:Drosophila Proteins; C520675:Dscam2 protein, Drosophila; D019006:Neural Cell Adhesion Molecules