title: RNA-binding protein Hermes/RBPMS inversely affects synapse density and axon arbor formation in retinal ganglion cells in vivo.
abstract: The RNA-binding protein Hermes [RNA-binding protein with multiple splicing (RBPMS)] is expressed exclusively in retinal ganglion cells (RGCs) in the CNS, but its function in these cells is not known. Here we show that Hermes protein translocates in granules from RGC bodies down the growing axons. Hermes loss of function in both Xenopus laevis and zebrafish embryos leads to a significant reduction in retinal axon arbor complexity in the optic tectum, and expression of a dominant acting mutant Hermes protein, defective in RNA-granule localization, causes similar defects in arborization. Time-lapse analysis of branch dynamics reveals that the decrease in arbor complexity is caused by a reduction in new branches rather than a decrease in branch stability. Surprisingly, Hermes depletion also leads to enhanced early visual behavior and an increase in the density of presynaptic puncta, suggesting that reduced arborization is accompanied by increased synaptogenesis to maintain synapse number.
authors.affiliation: Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, United Kingdom.
authors.forename: Hanna
authors.initials: H
authors.lastname: Hörnberg
authors.forename: Francis
authors.initials: F
authors.lastname: Wollerton-van Horck
authors.forename: Daniel
authors.initials: D
authors.lastname: Maurus
authors.forename: Maarten
authors.initials: M
authors.lastname: Zwart
authors.forename: Hanno
authors.initials: H
authors.lastname: Svoboda
authors.forename: William A
authors.initials: WA
authors.lastname: Harris
authors.forename: Christine E
authors.initials: CE
authors.lastname: Holt
mesh_terms: D000818:Animals; D001369:Axons / Q000502:physiology*; D001522:Behavior, Animal / Q000502:physiology; D015153:Blotting, Western; D002454:Cell Differentiation / Q000502:physiology; D002478:Cells, Cultured; D004247:DNA / Q000235:genetics; D018274:Electroporation; D004625:Embryo, Nonmammalian; D005260:Female; D006706:Homeostasis / Q000502:physiology; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D018613:Microscopy, Confocal; D010957:Plasmids / Q000235:genetics; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D016601:RNA-Binding Proteins / Q000502:physiology*; D012160:Retina / Q000254:growth & development / Q000502:physiology; D012165:Retinal Ganglion Cells / Q000502:physiology*; D013569:Synapses / Q000502:physiology*; D014785:Vision, Ocular / Q000502:physiology; D014981:Xenopus; D029867:Xenopus Proteins / Q000502:physiology*; D015027:Zebrafish / Q000502:physiology
chemical_list: C485602:RBPMS2 protein, Xenopus; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D029867:Xenopus Proteins; D004247:DNA