近日,,國際著名雜志Science在線刊登了臺灣研究人員的最新研究成果“Visualizing Long-Term Memory Formation in Two Neurons of the Drosophila Brain,,”,,文章中,作者通過研究發(fā)現(xiàn)果蠅記憶形成中的新的腦部成分,。
研究人員報告說,,在果蠅中,對長期記憶儲存至關(guān)重要的神經(jīng)元位于與記憶實際儲存的腦部位不同的地方,。 在剛經(jīng)歷某一事件后,,我們的記憶是豐富且鮮明的,,但這些記憶會隨著時間的推移而消退。 然而,,由于有一個叫做記憶鞏固的過程,,我們通常會記住重要的細節(jié)。 在一些物種中,,其中包括哺乳動物,,人們已經(jīng)證明,記憶鞏固依賴于神經(jīng)元產(chǎn)生的新的蛋白質(zhì),。 然而,,這一過程在此之前還沒有在任何的實驗系統(tǒng)中被觀察到。
人們長期以來認為,,在果蠅中,,這一蛋白質(zhì)的產(chǎn)生發(fā)生在被稱為蘑菇體的腦結(jié)構(gòu)中,該結(jié)構(gòu)常常被認為是昆蟲中聯(lián)想學習和記憶形成的部位,。 應(yīng)用熒光蛋白觀察控制這些蛋白合成的基因的表達,,Chun-Chao Chen及其在臺灣和美國的同事現(xiàn)在報告說,在果蠅的腦中,,這些新的蛋白質(zhì)是由2個背前外側(cè)神經(jīng)元產(chǎn)生的,,而不是在蘑菇體中的神經(jīng)元產(chǎn)生的。 在一則相關(guān)的《觀點欄目》中,,Josh Dubnau說,,這一發(fā)現(xiàn)改變了研究人員認為的有關(guān)記憶鞏固過程的途徑。(生物谷Bioon.com)
doi:10.1126/science.1212735
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Visualizing Long-Term Memory Formation in Two Neurons of the Drosophila Brain
Chun-Chao Chen1, Jie-Kai Wu1, Hsuan-Wen Lin1, Tsung-Pin Pai1, Tsai-Feng Fu3, Chia-Lin Wu2, Tim Tully4, Ann-Shyn Chiang1,2,5,6,*
Long-term memory (LTM) depends on the synthesis of new proteins. Using a temperature-sensitive ribosome-inactivating toxin to acutely inhibit protein synthesis, we screened individual neurons making new proteins after olfactory associative conditioning in Drosophila. Surprisingly, LTM was impaired after inhibiting protein synthesis in two dorsal-anterior-lateral (DAL) neurons but not in the mushroom body (MB), which is considered the adult learning and memory center. Using a photoconvertible fluorescent protein KAEDE to report de novo protein synthesis, we have directly visualized cyclic adenosine monophosphate (cAMP) response element–binding protein (CREB)–dependent transcriptional activation of calcium/calmodulin-dependent protein kinase II and period genes in the DAL neurons after spaced but not massed training. Memory retention was impaired by blocking neural output in DAL during retrieval but not during acquisition or consolidation. These findings suggest an extra-MB memory circuit in Drosophila: LTM consolidation (MB to DAL), storage (DAL), and retrieval (DAL to MB).