Post-Transcriptional Regulation of Cholinergic Genes

IBN-9723216果蝇胆碱能基因的转录后调控 PI：Toshihiro Kitamoto 神经元使用多种分子作为神经递质与其靶细胞进行通信。 特定神经递质表型（递质合成和释放所需的酶）的规范是神经回路有序构建和运行的基本过程，需要一组特定的神经递质特异性基因的协调表达。 本研究的目的是了解两个胆碱能神经元特异性基因的调控机制，这两个基因编码乙酰胆碱合成的胆碱乙酰转移酶（ChAT）和囊泡乙酰胆碱转运蛋白 （VAChT）用于将乙酰胆碱包装到突触囊泡中。 最近已经证明，ChAT和VAChT基因被组织成一个“胆碱能”基因座，其中后者基因嵌套在前者内。 这种独特的组织胆碱能基因座，保守的远亲物种，表明新的转录后机制参与协调调节这两个基因。 因此，该项目将特别关注以果蝇为模式生物的ChAT和VAChT基因的mRNA加工和翻译机制。 首先，将使用可用于果蝇的P元件介导的转化技术来创建携带适当报告基因的转基因动物。 ChAT和VAChT生产的机制将通过定性和定量分析转化体神经系统中的报告基因表达进行研究。 第二，果蝇VAChT突变体将被分离，其表型将被仔细表征。 VAChT突变体连同已经可用的ChAT突变体将被用来检查改变乙酰胆碱代谢对胆碱能基因的调节的影响。 使用分子和经典遗传学的拟议研究将提供一个有趣的新机制调节协调表达的两个胆碱能基因的更清晰的画面。

IBN-9723216 Post-transcriptional regulation of the Drosophila cholinergic genes PI: Toshihiro Kitamoto Neurons use a variety of molecules as neurotransmitters to communicate with their target cells. Specification of particular neurotransmitter phenotypes (enzymes required for transmitter synthesis and release) is a fundamental process for orderly construction and operation of neural circuits, and requires coordinated expression of a particular set of neurotransmitter-specific genes. The objective of this proposed research is to understand the regulatory mechanism for two cholinergic neuron-specific genes, encoding choline acetyltransferase (ChAT) for biosynthesis of acetylcholine and vesicular acetylcholine transporter (VAChT) for packaging acetylcholine into synaptic vesicles. It has recently been demonstrated that the ChAT and VAChT genes are organized into a "cholinergic" locus where the latter gene is nested within the former. This unique organization of the cholinergic locus, conserved among distantly related species, suggests that novel post-transcriptional mechanisms are involved in coordinated regulation of these two genes. The project will thus specifically focus on mRNA processing and translation mechanisms of the ChAT and VAChT genes using Drosophila melanogaster as a model organism. First, transgenic animals that carry appropriate reporter genes will be created using P-element mediated transformation technology available for Drosophila. The mechanisms for ChAT and VAChT production will be investigated by qualitative and quantitative analyses of reporter gene expression in the nervous system of the transformants. Second, Drosophila VAChT mutants will be isolated and their phenotypes will be carefully characterized. VAChT mutants together with already available ChAT mutants will be used to examine the effects of altered acetylcholine metabolism on regulation of the cholinergic genes. The proposed research using molecu lar and classical genetics will provide a clearer picture of interesting new mechanisms regulating coordinated expression of the two cholinergic genes.