PLoS Biology (Jan 2020)

SK2 channels in cerebellar Purkinje cells contribute to excitability modulation in motor-learning-specific memory traces.

  • Giorgio Grasselli,
  • Henk-Jan Boele,
  • Heather K Titley,
  • Nora Bradford,
  • Lisa van Beers,
  • Lindsey Jay,
  • Gerco C Beekhof,
  • Silas E Busch,
  • Chris I De Zeeuw,
  • Martijn Schonewille,
  • Christian Hansel

DOI
https://doi.org/10.1371/journal.pbio.3000596
Journal volume & issue
Vol. 18, no. 1
p. e3000596

Abstract

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Neurons store information by changing synaptic input weights. In addition, they can adjust their membrane excitability to alter spike output. Here, we demonstrate a role of such "intrinsic plasticity" in behavioral learning in a mouse model that allows us to detect specific consequences of absent excitability modulation. Mice with a Purkinje-cell-specific knockout (KO) of the calcium-activated K+ channel SK2 (L7-SK2) show intact vestibulo-ocular reflex (VOR) gain adaptation but impaired eyeblink conditioning (EBC), which relies on the ability to establish associations between stimuli, with the eyelid closure itself depending on a transient suppression of spike firing. In these mice, the intrinsic plasticity of Purkinje cells is prevented without affecting long-term depression or potentiation at their parallel fiber (PF) input. In contrast to the typical spike pattern of EBC-supporting zebrin-negative Purkinje cells, L7-SK2 neurons show reduced background spiking but enhanced excitability. Thus, SK2 plasticity and excitability modulation are essential for specific forms of motor learning.