Cerebellar long-term synaptic depression requires PKC-mediated activation of CPI-17, a myosin/moesin phosphatase inhibitor

Masumi Eto, Roland Bock, David L. Brautigan, David J Linden

Research output: Contribution to journalArticle


Cerebellar LTD requires brief activation of PKC and is expressed as a functional downregulation of AMPA receptors. Modulation of vascular smooth-muscle contraction by G protein-coupled receptors (called Ca2+ sensitization) also involves PKC phosphorylation and activation of a specific inhibitor of myosin/moesin phosphatase (MMP). This inhibitor, called CPI-17, is also expressed in brain. Here, we tested the hypothesis that LTD, like Ca2+ sensitization, employs a PKC/CPI-17 cascade. Introduction of activated recombinant CPI-17 into cells produced a use-dependent attenuation of glutamate-evoked responses and occluded subsequent LTD. Moreover, the requirement for endogenous CPI-17 in LTD was demonstrated with neutralizing antibodies plus gene silencing by siRNA. These interventions had no effect on basal synaptic strength but blocked LTD induction. Thus, a biochemical circuit that involves PKC-mediated activation of CPI-17 modulates the distinct physiological processes of vascular contractility and cerebellar LTD.

Original languageEnglish (US)
Pages (from-to)1145-1158
Number of pages14
Issue number6
Publication statusPublished - Dec 19 2002


ASJC Scopus subject areas

  • Neuroscience(all)

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