Delayed wave of c-Fos expression in the dorsal hippocampus involved specifically in persistence of long-term memory storage

Proc Natl Acad Sci U S A. 2010 Jan 5;107(1):349-54. doi: 10.1073/pnas.0912931107. Epub 2009 Dec 14.

Abstract

Memory formation is a temporally graded process during which transcription and translation steps are required in the first hours after acquisition. Although persistence is a key characteristic of memory storage, its mechanisms are scarcely characterized. Here, we show that long-lasting but not short-lived inhibitory avoidance long-term memory is associated with a delayed expression of c-Fos in the hippocampus. Importantly, this late wave of c-Fos is necessary for maintenance of inhibitory avoidance long-term storage. Moreover, inhibition of transcription in the dorsal hippocampus 24 h after training hinders persistence but not formation of long-term storage. These findings indicate that a delayed phase of transcription is essential for maintenance of a hippocampus-dependent memory trace. Our results support the hypothesis that recurrent rounds of consolidation-like events take place late after learning in the dorsal hippocampus to maintain memories.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Avoidance Learning / physiology
  • Conditioning, Classical
  • Hippocampus* / anatomy & histology
  • Hippocampus* / metabolism
  • Hippocampus* / physiology
  • Male
  • Memory / physiology*
  • Protein Biosynthesis
  • Proto-Oncogene Proteins c-fos / genetics
  • Proto-Oncogene Proteins c-fos / metabolism*
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats
  • Rats, Wistar
  • Transcription, Genetic

Substances

  • Proto-Oncogene Proteins c-fos
  • RNA, Messenger