These authors contributed equally to this work.
Protein degradation, as with protein synthesis, is required during not only long-term spatial memory consolidation but also reconsolidation
Article first published online: 28 JUN 2008
© The Authors (2008). Journal Compilation © Federation of European Neuroscience Societies and Blackwell Publishing Ltd
European Journal of Neuroscience
Volume 27, Issue 11, pages 3009–3019, June 2008
How to Cite
Artinian, J., McGauran, A.-M. T., De Jaeger, X., Mouledous, L., Frances, B. and Roullet, P. (2008), Protein degradation, as with protein synthesis, is required during not only long-term spatial memory consolidation but also reconsolidation. European Journal of Neuroscience, 27: 3009–3019. doi: 10.1111/j.1460-9568.2008.06262.x
- Issue published online: 28 JUN 2008
- Article first published online: 28 JUN 2008
- Received 19 October 2007, revised 9 April 2008, accepted 11 April 2008
- spatial learning
The formation of long-term memory requires protein synthesis, particularly during initial memory consolidation. This process also seems to be dependant upon protein degradation, particularly degradation by the ubiquitin-proteasome system. The aim of this study was to investigate the temporal requirement of protein synthesis and degradation during the initial consolidation of allocentric spatial learning. As memory returns to a labile state during reactivation, we also focus on the role of protein synthesis and degradation during memory reconsolidation of this spatial learning. Male CD1 mice were submitted to massed training in the spatial version of the Morris water maze. At various time intervals after initial acquisition or after a reactivation trial taking place 24 h after acquisition, mice received an injection of either the protein synthesis inhibitor anisomycin or the protein degradation inhibitor lactacystin. This injection was performed into the hippocampal CA3 region, which is specifically implicated in the processing of spatial information. Results show that, in the CA3 hippocampal region, consolidation of an allocentric spatial learning task requires two waves of protein synthesis taking place immediately and 4 h after acquisition, whereas reconsolidation requires only the first wave. However, for protein degradation, both consolidation and reconsolidation require only one wave, taking place immediately after acquisition or reactivation, respectively. These findings suggest that protein degradation is a key step for memory reconsolidation, as for consolidation. Moreover, as protein synthesis-dependent reconsolidation occurred faster than consolidation, reconsolidation did not consist of a simple repetition of the initial consolidation.