Dynamic aspects of long-term memory: A comparative study of mouse and Aplysia

Abstract

Short-term memory can be transformed to more stable long-term memory via so called consolidation process. A great body of evidence, however, indicates that the retrieval process of consolidated memory is quite dynamic. Long-term memory becomes labile particularly during the retrieval process. Thus, memory retrieval is believed to be an updating process required to incorporate new information into preexisting memories. I will discuss how it occurs by showing that postsynaptic proteins are degraded in the hippocampus by the ubiquitin/proteasome system after retrieval of contextual fear memory. In addition, our data show that synaptic protein degradation also plays a critical role in memory extinction, suggesting that memory retrieval and extinction could share a common mechanism in the process of memory reorganization. Finally, I will discuss evidence suggesting that the key molecular mechanisms involved in memory reconsolidation are evolutionally conserved between the marine snail Aplysia and mammals. Bong-Kiun Kaang博士は長期記憶の形成・固定・再固定・消去の分子機構研究の第1人者で、Molecular Brain誌の編集長としても目覚しい活躍をされています。この度、日本神経科学学会年会ならびにアジ ア分子細胞認知学会ご出席のために来日された折に、ご講演いただく機会を得ましたので、興味のあ る方はどうか奮ってご参加下さい。