Molecular Substrates of Translation in Specific Neuronal Compartments During Memory Storage

 描述(申请人提供)：尽管我们理解长期记忆(LTM)的巩固需要新的蛋白质合成，但翻译的特定分子底物仍有待详细了解。最近的研究已经描述了几种神经精神障碍的蛋白质合成异常。重要的是，在特定脑区抑制翻译的治疗潜力已被描述为治疗创伤后应激障碍(PTSD)。因此，更好地了解翻译的分子底物将有助于开发治疗创伤后应激障碍等疾病的新疗法。从我们自己的研究中得出的这一建议的中心假设是，建立LTM需要激活突触前和突触后神经元特定隔区中特定mRNAs的翻译。为了验证这一假说，我们将通过探索最近描述的多聚核糖体标记(TRAP：翻译核糖体亲和力纯化)的优势和海螺撤鳃反射(GWR)的神经电路来确定特定突触前和突触后神经元区室中翻译的分子底物。具体地说，我们将(1)分离和鉴定从GWR的突触前和突触后神经元的体细胞和突触区段中标记的多核糖体免疫共沉淀，这些多核糖体是海螺学习中的一种重要神经递质；(2)通过敲除特定候选基因和电生理分析来表征它们在记忆存储中的功能。我们预计，这些研究将首次描述神经回路特定突触前和突触后区段的翻译分子底物及其在记忆存储过程中的时间调节。此外，这些研究还将为研究翻译过程中的翻译动态提供新的视角。这些研究将对我们对神经回路功能和记忆储存的基本理解产生重要的积极影响，并有可能为记忆障碍的预防和治疗干预找到新的靶点。

 DESCRIPTION (provided by applicant): Despite our understanding that consolidation of long-term memories (LTM) require new protein synthesis, the specific molecular substrates of translation are yet to be understood in detail. Recent studies have described abnormal protein synthesis in several neuropsychiatric disorders. Importantly, therapeutic potential of inhibition o translation in specific brain regions for treating Post-traumatic stress disorder (PTSD) have been described. Thus, better understanding of the molecular substrates of translation will help develop novel therapeutic treatments for disorders such as PTSD. The central hypothesis of this proposal derived from our own studies is that activation of translation of specific mRNAs in specific compartments of pre and postsynaptic neurons is required for establishing LTM. To test this hypothesis, we will identify molecular substrates of translation in specific neuronal compartments of pre and postsynaptic neurons by exploring the advantages of recently described tagging of polyribosomes (TRAP: Translating ribosome affinity purification) and well- characterized neural circuitry of gill-withdrawal reflex (GWR) of marine snail, Aplysia californica Specifically we will (1) isolate and characterize tagged polyribosomes immunoprecipitated from somatic and synaptic compartments of pre and post synaptic neurons of GWR that are exposed 5HT, a neurotransmitter important for learning in Aplysia and (2) characterize their function in memory storage by knockdown of specific candidates and electrophysiological analysis. We anticipate that these studies will provide the first ever description of molecular substrates of translation in specific pre and postsynaptic compartments of a neural circuitry and their temporal regulation during memory storage. Furthermore these studies will bring novel insights into dynamics of translation during LTM. These studies will have an important positive impact on our fundamental understanding of neural circuit function and memory storage and likely lead to identification of new targets for preventive and therapeutic interventions of memory disorders.