title: Neurexin Restricts Axonal Branching in Columns by Promoting Ephrin Clustering.
abstract: Columnar restriction of neurites is critical for forming nonoverlapping receptive fields and preserving spatial sensory information from the periphery in both vertebrate and invertebrate nervous systems, but the underlying molecular mechanisms remain largely unknown. Here, we demonstrate that Drosophila homolog of α-neurexin (DNrx) plays an essential role in columnar restriction during L4 axon branching. Depletion of DNrx from L4 neurons resulted in misprojection of L4 axonal branches into neighboring columns due to impaired ephrin clustering. The proper ephrin clustering requires its interaction with the intracellular region of DNrx. Furthermore, we find that Drosophila neuroligin 4 (DNlg4) in Tm2 neurons binds to DNrx and initiates DNrx clustering in L4 neurons, which subsequently induces ephrin clustering. Our study demonstrates that DNrx promotes ephrin clustering and reveals that ephrin/Eph signaling from adjacent L4 neurons restricts axonal branches of L4 neurons in columns.
authors.affiliation: Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Liu
authors.affiliation: Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China.
authors.forename: Xiao-Yan
authors.initials: XY
authors.lastname: Zhang
authors.affiliation: Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China.
authors.forename: Xinwang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xie
authors.affiliation: Institute of Life Sciences, Key Laboratory of Developmental Genes and Human Disease, Southeast University, 2 Sipailou Road, Nanjing 210096, China; Co-innovation Center of Neuroregeneration, Nantong University, Nantong 226001, China. Electronic address: junhaihan@seu.edu.cn.
authors.forename: Junhai
authors.initials: J
authors.lastname: Han
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism*; D015816:Cell Adhesion Molecules, Neuronal / Q000378:metabolism*; D029721:Drosophila Proteins / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D011679:Pupa / Q000378:metabolism
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D029721:Drosophila Proteins; C467458:Ephrin protein, Drosophila; D008565:Membrane Proteins; C584506:Nlg4 protein, Drosophila; C491321:Nrx protein, Drosophila
keywords: Drosophila; axon projection; axonal branching; clustering; columnar restriction; eph; ephrin; neurexin; neuroligin; vision