果蝇蘑菇体亚结构在嗅觉长时记忆固化中的门控作用

发布时间：2018-11-24 14:03

【摘要】：记忆是神经系统最基本的功能之一。对于不同经历，记忆可强可弱，可长可短，这可能是因为神经系统需要确保只有最重要的信息才被长期的储存。目前，这其中的调控机制还很不清楚。果蝇学习记忆的相关研究发现，惩罚性长时记忆的形成需要经过多次间隔的训练，，而与觅食相关的奖赏性记忆则只需要一次训练就能形成长时记忆。虽然在强大的遗传学操作和工具的帮助下，大量与果蝇长时记忆相关的基因和脑区被揭示出来，但是要真正了解长时程记忆调控的原理，仍然需要不断发现新的分子和深入的研究神经回路机制。本研究发现在果蝇Hiw蛋白的活性下调的情况下，单次惩罚性训练便可诱导长时记忆的形成。Hiw通过其E3泛素连接酶活性生理性的参与到长时记忆的调控当中。而且，Hiw蛋白可以特异的在蘑菇体α/β core神经元内调控下游Wnd/JNK信号通路，并最终影响长时记忆的形成。研究还发现蘑菇体α/β core亚结构在长时记忆的获取和取回过程中不发挥作用，但是却参与调控了惩罚性和奖赏性长时记忆的固化过程。同时，蘑菇体α/β surface亚结构特异的参与调控两种长时记忆的取回过程。这些结果使我们提出了果蝇长时记忆的门控假说：蘑菇体α/β core亚结构的功能就像是一道闸门，能够决定长时记忆是否形成，而任何能开启这一门控机制的经历都能形成长时程记忆。
[Abstract]:Memory is one of the most basic functions of the nervous system. For different experiences, memory can be strong or weak, long or short, probably because the nervous system needs to ensure that only the most important information is stored for a long time. At present, the regulation and control mechanism is not clear. Studies on learning and memory of Drosophila have found that the formation of punitive long term memory requires multiple interval training while reward memory associated with foraging requires only one training to form long term memory. Although a large number of genes and brain regions related to the long term memory of Drosophila have been revealed with the help of powerful genetic techniques and tools, it is important to really understand the mechanism of the regulation of long term memory. New molecules and further studies of neural circuit mechanisms are still needed. In this study, it was found that under the condition of down-regulation of Hiw protein activity in Drosophila melanogaster, a single punitive training could induce the formation of long-term memory. Hiw physiologically participated in the regulation of long-term memory through its E3 ubiquitin ligase activity. Moreover, Hiw protein can specifically regulate the downstream Wnd/JNK signaling pathway in the 伪 / 尾 core neurons of mushroom body, and ultimately affect the formation of long-term memory. It was also found that the 伪 / 尾 core substructure of mushroom body did not play a role in the acquisition and retrieval of long-term memory, but it was involved in the process of punitive and rewarding long-term memory solidification. At the same time, the 伪 / 尾 surface substructure of mushroom body was specifically involved in regulating the retrieval of two kinds of long term memory. These results have led us to propose a gating hypothesis for Drosophila's long-term memory: the function of the 伪 / 尾 core substructure of the mushroom body is like a gate that determines whether long-term memory is formed or not. Any experience that opens this gated mechanism can form long-term memory.
【学位授予单位】：清华大学
【学位级别】：博士
【学位授予年份】：2012
【分类号】：R338

【共引文献】