摘要
長期記憶之形成需要新的蛋白質合成，我們透過使用溫度敏感型核糖體失活毒素蛋白準確抑制新蛋白質生成，來篩選果蠅腦中特定神經元，負責合成新蛋白並且儲存經過嗅覺關聯性學習後產生的長期記憶。意外發現抑制果蠅腦中的一對dorsal-anterior-lateral (DAL)神經元的新蛋白生成會使長期記憶損壞，而在一般認為是學習與記憶的中心的蕈狀體細胞中抑制新蛋白生成，則不影響長期記憶的形成。而經由使用光轉換變色螢光蛋白KAEDE來監測新生成的蛋白，我們在DAL神經元內直接觀察到受cyclic adenosine monophosphate (cAMP) response element–binding protein (CREB)調控下的calcium/calmodulin-dependent protein kinase II 與 period 二個基因基因轉錄活性增加，而這樣的現象只發生在果蠅經過可形成長期記憶間斷式的學習之後，而非無法形成長期記憶的連續性的學習過程之後。透過在記憶的讀取時阻斷抑制DAL神經細胞的傳導，會影響長期記憶，而在記憶的獲得或記憶的固化階段抑制則不影響長期記憶。這些發現支持在果蠅腦中存在有蕈狀體以外的記憶線路：長期記憶的固化(蕈狀體 DAL神經細胞)，儲存記憶（DAL神經細胞）和提取記憶(DAL神經細胞蕈狀體)。

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