Two waves of proteasome-dependent protein degradation in the hippocampus are required for recognition memory consolidation

Neurobiol Learn Mem. 2015 Apr:120:1-6. doi: 10.1016/j.nlm.2015.02.005. Epub 2015 Feb 14.

Abstract

Healthy neuronal function and synaptic modification require a concert of synthesis and degradation of proteins. Increasing evidence indicates that protein turnover mediated by proteasome activity is involved in long-term synaptic plasticity and memory. However, its role in different phases of memory remains debated, and previous studies have not examined the possible requirement of protein degradation in recognition memory. Here, we show that the proteasome inhibitor, lactacystin (LAC), infused into the CA1 area of the hippocampus at two specific time points during consolidation, impairs 24-retention of memory for object recognition in rats. Administration of LAC after retrieval did not affect retention. These findings provide the first evidence for a requirement of proteasome activity in recognition memory, indicate that protein degradation in the hippocampus is necessary during selective time windows of memory consolidation, and further our understanding of the role of protein turnover in memory formation.

Keywords: Hippocampus; Lactacystin; Object recognition; Proteasome; Protein degradation; Recognition memory.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcysteine / analogs & derivatives
  • Acetylcysteine / pharmacology
  • Animals
  • CA1 Region, Hippocampal / drug effects
  • CA1 Region, Hippocampal / metabolism
  • CA1 Region, Hippocampal / physiology
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Hippocampus / physiology*
  • Infusions, Intraventricular
  • Male
  • Memory Consolidation / physiology*
  • Proteasome Endopeptidase Complex / drug effects
  • Proteasome Endopeptidase Complex / metabolism
  • Proteasome Endopeptidase Complex / physiology*
  • Proteolysis
  • Rats
  • Rats, Wistar
  • Recognition, Psychology / physiology*
  • Retention, Psychology / physiology

Substances

  • lactacystin
  • Proteasome Endopeptidase Complex
  • Acetylcysteine