AMINO ACID REGULATION OF GENE EXPRESSION IN NEURAL CELLS

充足的氨基酸(AA)营养对健康和健康是必不可少的 属于人类和动物一样的。由于AA没有存储池，因此 严重的AA缺乏症发生得很快，尤其是 如果蛋白质缺乏的轻度状态已经存在。自AA以来 补充剂已经变得流行起来，尤其可能被 节食者，AA失衡应被认为是一种潜在的健康危害。 此外，癌症恶病质、AA代谢障碍、 而其他代谢异常也可能出现AA比例失调。AA 已有研究表明，缺陷会影响生长和身体功能。 这取决于蛋白质合成，比如伤口愈合。然而， 由于AA失衡导致的增长减速实际上是次要的 食物摄入量减少，这是对AA缺乏的厌食反应。这个 该实验室工作的长期目标是了解AA如何 身体识别缺陷，以及这种缺陷是如何表现出来的 在一个现成的行为测量中，食物摄入量。给定 AA营养的重要性，我们必须获得更好的 对AA失衡影响的基本机制的理解 进食行为。 使用AA不平衡(IMB)饮食的一个定义良好的营养模型是 可用于这些研究。大脑的梨状皮质(PC)有 被认为是氨基酸缺乏的感受器的主要候选者 IMB饮食模式。摄入IMB后PC中的主要事件是 极限AA浓度的下降。我们还确定了 去甲肾上腺素、cAMP、一氧化氮、5-羟色胺和RNA的变化 蛋白质合成可能参与了对IMB的神经反应。 然而，尽管我们已经确定这些不同的系统是 ，我们不知道它们是如何与限制AA相互作用的 对IMB的初始分子和细胞反应。因此，少校 本研究的目的是确定其分子机制。 对饮食的认可和拒绝负责 AA缺乏症。具体地说，我们将确定氨基酸如何调节 PC区神经元的基因表达。以下三个具体目标 将解决这些问题：特定目标1：获得基因和基因组 与受氨基酸缺乏调控的基因相对应的克隆 PC，使用差异显示和消减文库。 特异性目的2：进一步发展一种体外分析系统 PC中的氨基酸使用初级氨基酸进行的复杂调节 神经元培养。特异目的3：确定tRNA氨酰化 PC神经元对氨基酸缺乏的反应水平发生变化。

Adequate amino acid (AA) nutrition is essential for the health and well- being of humans and animals alike. Because AAs have no storage pool, the development of an essential AA deficiency can occur rapidly, particularly if a mild state of protein deficiency already exists. Since AA supplements have become fashionable, and may especially be used by dieters, AA imbalance should be recognized as a potential health hazard. Moreover, individuals with cancer cachexia, disorders of AA metabolism, and other metabolic aberrancies may also suffer AA disproportion. AA deficiencies have been shown to compromise growth and any bodily function that depends on protein synthesis, such as wound healing. However, the growth reduction attributed to AA imbalance is actually secondary to the decreased food intake, an anorectic response to the AA deficiency. The long-term goal of the work in this laboratory is to understand how AA deficiency is recognized by the body, and how this deficiency is expressed in a readily available behavioral measure, food intake. Given the importance of AA nutrition, it is imperative that we gain a better understanding of the basic mechanisms by which AA imbalance affects feeding behavior. A well defined nutritional model using AA imbalanced (IMB) diets is available for these studies. The piriform cortex (PC) of the brain has been implicated as the prime candidate for the sensor of AA deficiency in the IMB-diet model. The primary event in the PC after ingestion of IMB is a drop in the concentration of the limiting AA. We have also determined that norepinephrine, cAMP, nitric oxide, serotonin and alterations in RNA and protein synthesis may be involved in the neural responses to IMB. However, although we have identified these different systems as being involved, we do not understand how they interact with the limiting AA in the initial molecular and cellular responses to IMB. Therefore, the major objective of this research is to determine the molecular mechanisms responsible for the recognition and rejection of diets that result in an AA deficiency. Specifically, we will determine how amino acids regulate gene expression in neurons of the PC. The following three Specific Aims will address these questions: SPECIFIC AIM 1: To obtain cDNA and genomic clones that correspond to genes regulated by amino acid deficiency in the PC, using both differential display and a subtracted cDNA library. SPECIFIC AIM 2: To further develop an in vitro system to dissect the complex regulation that occurs by amino acids in the PC using primary neuron cultures. SPECIFIC AIM 3: To determine if tRNA aminoacylation levels change in response to amino acid deficiency in PC neurons.