Postsynaptic CPG15 promotes synaptic maturation and presynaptic axon arbor elaboration in vivo

Nat Neurosci. 2000 Oct;3(10):1004-11. doi: 10.1038/79823.

Abstract

The formation of CNS circuits is characterized by the coordinated development of neuronal structure and synaptic function. The activity-regulated candidate plasticity gene 15 (cpg15) encodes a glycosylphosphatidylinositol (GPI)-linked protein whose in vivo expression increases the dendritic arbor growth rate of Xenopus optic tectal cells. We now demonstrate that tectal cell expression of CPG15 significantly increases the elaboration of presynaptic retinal axons by decreasing rates of branch retractions. Whole-cell recordings from optic tectal neurons indicate that CPG15 expression promotes retinotectal synapse maturation by recruiting functional AMPA receptors to synapses. Expression of truncated CPG15, lacking its GPI anchor, does not promote axon arbor growth and blocks synaptic maturation. These results suggest that CPG15 coordinately increases the growth of pre- and postsynaptic structures and the number and strength of their synaptic contacts.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Afferent Pathways / growth & development*
  • Afferent Pathways / metabolism
  • Afferent Pathways / ultrastructure
  • Age Factors
  • Animals
  • Axons / metabolism*
  • Axons / ultrastructure
  • Cell Communication / physiology
  • Dendrites / metabolism
  • Dendrites / ultrastructure
  • Gene Expression Regulation, Developmental
  • Genes, Reporter / physiology
  • Growth Cones / metabolism*
  • Growth Cones / ultrastructure
  • Larva
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Nerve Tissue Proteins*
  • Receptors, AMPA / metabolism
  • Receptors, N-Methyl-D-Aspartate / metabolism
  • Retina / growth & development*
  • Retina / metabolism
  • Retina / ultrastructure
  • Superior Colliculi / growth & development*
  • Superior Colliculi / metabolism
  • Superior Colliculi / ultrastructure
  • Synapses / metabolism*
  • Synapses / ultrastructure
  • Synaptic Transmission / physiology
  • Xenopus laevis
  • beta-Galactosidase / genetics

Substances

  • Membrane Proteins
  • NRN1 protein, Xenopus
  • Nerve Tissue Proteins
  • Receptors, AMPA
  • Receptors, N-Methyl-D-Aspartate
  • beta-Galactosidase