Regulation of the Reelin Gene

描述（由申请人提供）：在胚胎脑发育期间， 由Cajal-Retzius（CR）细胞分泌到细胞外基质（ECM）中， 在发育过程中协调迁移神经元的定位 皮质海马和小脑在成年大鼠的大脑皮层中， 从GABA能神经元的亚群分泌到ECM中， 构成机制在成年非人类灵长类动物中，存在于 ECM与在ECM附近的含α 3的整联蛋白受体邻接。 树突棘这就提出了一种可能性，即成人的reelin-integrin 相互作用可能有助于突触可塑性通过调节表达 促进树突棘营养作用的细胞骨架蛋白。在 精神分裂症患者的死后大脑，基底树突棘密度 减少了。此外，在从被诊断患有 精神分裂症和双相情感障碍伴精神病，reelin mRNA和蛋白 水平降低了约50%。基因组胞嘧啶甲基化 DNA影响细胞过程的全貌，包括基因转录， 基因组印记和基因组稳定性。在此概述的实验 应用程序将扩展我们的初步数据，支持我们的假设 人reelin启动子受DNA甲基化调控， 通过染色质的改变决定转录因子的可及性 结构我们的目标是获得有关负责机制的信息， reelin基因表达的适当时间和空间模式。我们 将定义在调节卷绕过程中起作用的启动子的那些部分， 在原代神经元细胞培养物（皮质神经元和神经胶质， 小脑颗粒神经元）。利用这些信息，我们将 与这些调控区域相互作用的反式作用因子（Aim 1）。 其次，我们还将关注DNA甲基化在定义 reelin基因在体外神经元前体细胞分化中的表达 (Aim 2）。最后，我们将使用reelin启动子产生转基因动物 驱动lacZ报告基因的表达，并检查这些基因的作用， 调节序列在靶向神经元表达cDNAN中的作用（Aim 1）。我们将 在不同的细胞中检测人启动子转基因的甲基化模式， 来自这些转基因小鼠的原代培养物（目的2），并将比较 内源基因甲基化的模式与人类reelin 转基因。从拟议的实验中获得的信息将提供 一个框架，以制定有关机制的假设，其中缫丝 在精神疾病中表达可能在功能上受损。最后， 对负责调节reelin表达的事件的理解可以 为将来如何操纵这种基因提供了初步线索 作为一种潜在的治疗方法来治疗这些复杂的精神疾病。

DESCRIPTION (provided by applicant): During embryonic brain development, reelin is secreted by Cajal-Retzius (CR) cells into the extracellular matrix (ECM) and serves to orchestrate the positioning of migrating neurons in the developing cortex, hippocampus and cerebellum. In the cortex of adult rat, reelin is secreted from a subpopulation of GABAergic neurons into the ECM by a constitutive mechanism. In adult non-human primates, reelin, present in the ECM, is contiguous with alpha3-containing integrin receptors in the vicinity of dendritic spines. This raises the possibility that adult reelin-integrin interactions may contribute to synaptic plasticity by modulating the expression of cytoskeletal proteins that facilitate the trophism of dendritic spines. In the post-mortem brains of schizophrenia patients, basal dendritic spine density is decreased. Moreover, in brains obtained from patients diagnosed with schizophrenia and bipolar illness with psychosis, reelin mRNA and protein levels are reduced by approximately 50 percent. Cytosine methylation of genomic DNA influences a panorama of cellular processes, including gene transcription, genomic imprinting, and genome stability. Experiments outlined in this application will expand upon our preliminary data that support our hypothesis that the human reelin promoter is modulated by DNA methylation, which determines transcription factor accessibility through alterations in chromatin structure. Our goal is to obtain information relevant to mechanisms responsible for appropriate temporal and spatial patterns of reelin gene expression. We will define those parts of the promoter operative in modulating reelin expression in primary neuronal cell cultures (cortical neurons and glia and cerebellar granule neurons). Using this information, we will identify trans-acting factors that interact with these regulatory regions (Aim 1). Secondly, we will also focus on the role that DNA methylation plays in defining reelin gene (RELN) expression in neuronal precursors differentiating in vitro (Aim 2). Finally, we will generate transgenic animals using the reelin promoter to drive expression of a lacZ reporter gene and examine the role of these regulatory sequences in targeting neuronal expression of RELN (Aim 1). We will examine the methylation pattern of the human promoter transgene in various primary cultures derived from these transgenic mice (Aim 2) and will compare the patterns of methylation of the endogenous gene with the human reelin transgene. Information obtained from the proposed experiments will provide the framework for formulating hypotheses relevant to mechanisms by which reelin expression may be functionally compromised in psychiatric diseases. Ultimately, an understanding of events responsible for modulating reelin expression may provide preliminary clues as to how the gene might be manipulated in the future as one potential therapeutic approach to these complex mental disorders.