Functional Anatomy of Learning and Memory in Drosophila

描述（由申请人提供）：行为水平的研究表明，在脊椎动物和无脊椎动物物种中，记忆巩固涉及通过几个不同的时间“阶段”处理信息。在解剖学层面上，记忆在许多情况下似乎是在不同的位点之间动态转移的。在相对简单的无脊椎动物大脑中，即使是基本形式的联想学习，也可以依赖于相对较大的神经元网络中的多种机制。该提议的核心是在果蝇中可获得Gal 4响应性温度敏感性（和显性负性）发动蛋白转基因（UAS-Shi/ ts），其允许神经元功能的温度依赖性和可逆性破坏。这种遗传工具提供了一个独特的机会，可以在功能上映射神经回路和记忆等复杂行为之间的关系。我们已经用这种方法破坏了果蝇大脑几个不同子区域的神经元功能，从而剖析了获取与提取以及存储麻醉敏感与麻醉耐受记忆的解剖学要求。这个提议的目的是进一步定义记忆形成、存储和提取的功能电路。 该提案的三个具体目标是： 1-“功能解剖学”-这11个非蘑菇体Gal 4增强子系中的每一个以及Gal和MB系将用于驱动Gal 4响应性UAS-Shits转基因的空间限制性表达。然后，温度变化实验将用于在记忆巩固的每个时间阶段短暂地破坏这些病灶中的神经元功能。 2-“记忆阶段的解剖学解剖”-将在目标#1中鉴定的功能相关Gal 4系与“阶段特异性”健忘症和萝卜突变体组合。这种“双突变体”的方法将允许解剖的解剖要求健忘症依赖的记忆，这是麻醉敏感，从萝卜依赖（麻醉抗性）的记忆。 3-高分辨率成像-共聚焦成像将用于构建特定目的I和2中鉴定为功能相关的每个Gal 4转座子系的GFP报告基因表达的高分辨率解剖图。 我们将利用规模经济和分子遗传学工具，研究神经活动的时间和空间模式与大脑中记忆的持续巩固之间的关系。虽然神经系统的解剖接线图似乎具有物种特异性，但这些回路中记忆的分子机制和行为特性是非常保守的。因此，理解信息在相对简单的神经系统中如何处理的“逻辑”可以为未来人类认知的研究提供极大的信息。

DESCRIPTION (provided by applicant): Studies at the behavioral level reveal that in both vertebrate and invertebrate species, memory consolidation involves processing of information through several distinct temporal "phases". At the anatomical level, memories appear in many cases to be dynamically transferred between distinct loci. Even elemental forms of associative learning in relatively simple invertebrate brains can rely on multiple mechanisms in relatively large networks of neurons. Central to this proposal is the availability in flies of a Gal4-responsive temperature-sensitive (and dominant negative) dynamin transgene (UAS-Shi/ ts), which permits temperature dependent and reversible disruption of neuronal function. This genetic tool provides a unique opportunity to functionally map the relationships between neural circuitry and a complex behavior such as memory. We already have used this method to disrupt neuronal function in several distinct sub-regions of the fly brain, thereby dissecting the anatomical requirements for acquisition versus retrieval as well as for storage of anesthesia-sensitive versus anesthesia-resistant memory. The goal of this proposal is to further define the functional circuitry underlying memory formation, storage and retrieval. The three Specific Aims of this proposal are: 1- "Functional anatomy"- Each of these 11 non-mushroom body Gal4 enhancer lines, as well as the DPM and MB lines, will be used to drive spatially restricted expression of the Gal4-responsive UAS-Shits transgene. Temperature-shift experiments then will be used to transiently disrupt neuronal function in these foci during each temporal phase of memory consolidation. 2- "Anatomical Dissection of Memory Phases" - Functionally relevant Gal4 lines identified in Aim #1 will be combined with the "phase specific" amnesiac and radish mutants. This "double mutant" approach will permit dissection of the anatomical requirements for amnesiac-dependent memory, which is anesthesia sensitive, from radish-dependant (anesthesia resistant) memory. 3- High Resolution Imaging- Confocal imaging will be used to construct a high-resolution anatomical map of GFP reporter expression for each Gal4 transposon line identified as functionally relevant in Specific Aims I and 2. We will take advantage of the economy-of-scale and molecular genetic tools available only in flies to investigate the relationships between temporal and spatial patterns of neural activity and the ongoing consolidation of memories in the brain. While the anatomical wiring diagram of nervous systems appear species specific, the molecular mechanisms and behavioral properties underlying memory within these circuits are remarkably conserved. As a result, an understanding of the "logic" of how information is processed in relatively simple nervous systems can greatly inform future investigations of human cognition.