Insulin Receptor Signaling Regulates Synapse Number, Dendritic Plasticity, and Circuit Function In Vivo

Shu-Ling Chiu, Chih Ming Chen, Hollis T. Cline

Research output: Contribution to journalArticle

Abstract

Insulin receptor signaling has been postulated to play a role in synaptic plasticity; however, the function of the insulin receptor in CNS is not clear. To test whether insulin receptor signaling affects visual system function, we recorded light-evoked responses in optic tectal neurons in living Xenopus tadpoles. Tectal neurons transfected with dominant-negative insulin receptor (dnIR), which reduces insulin receptor phosphorylation, or morpholino against insulin receptor, which reduces total insulin receptor protein level, have significantly smaller light-evoked responses than controls. dnIR-expressing neurons have reduced synapse density as assessed by EM, decreased AMPA mEPSC frequency, and altered experience-dependent dendritic arbor structural plasticity, although synaptic vesicle release probability, assessed by paired-pulse responses, synapse maturation, assessed by AMPA/NMDA ratio and ultrastructural criteria, are unaffected by dnIR expression. These data indicate that insulin receptor signaling regulates circuit function and plasticity by controlling synapse density.

Original languageEnglish (US)
Pages (from-to)708-719
Number of pages12
JournalNeuron
Volume58
Issue number5
DOIs
Publication statusPublished - Jun 12 2008
Externally publishedYes

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Keywords

  • DEVBIO
  • MOLNEURO
  • SIGNALING

ASJC Scopus subject areas

  • Neuroscience(all)

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