Structure & Expression of Mammal ALC Dehydrogenase Genes

描述(申请人提供)：这项研究的长期目标是了解调节人类酒精脱氢酶(ADH)基因表达的机制，以及ADH表达变化的生理和病理后果。我们假设ADH基因表达的差异影响酒精的新陈代谢、酒精中毒的风险以及酒精消费的生理和病理后果。为了验证这一假说，我们将确定控制ADH表达的区域，确定这些区域的多态，然后分析这些多态是否影响基因表达。我们将确定在人类ADH基因调控中重要的顺式作用元件，主要集中在I类基因和ADH7。它们有不同的表达模式，并产生影响重要代谢过程的酶，包括乙醇和视黄醇的代谢。顺式作用元件将通过功能研究(转基因)和蛋白质结合分析(DNaseI足迹和凝胶延迟)相结合来确定。我们将鉴定与这些序列结合的转录因子。ADH基因聚集在4号染色体上，我们假设距离较远的侧翼序列对调节这组基因很重要。我们将通过研究更远的序列来检验这一假设，从编码区延伸至少10kb。我们还将分析携带ADH基因组的大染色体片段(BAC)的调节，以检测染色体环境中潜在的相互作用。我们假设个体间调控序列的差异导致ADH基因表达的差异。我们将识别和表征调控区域的多态，并测试它们对体外基因表达的影响。这两个目标将紧密结合在一起，顺式作用元件的本地化指导我们寻找多态，而我们对功能多态的检测有助于优先进行顺式作用元件的进一步研究。这些研究将有助于我们理解个体在饮酒的代谢、药理和病理影响方面存在差异的遗传因素。它们还将增加我们对基因调控的基本理解。

DESCRIPTION (provided by applicant): The long-term goals of this research are to understand the mechanisms that regulate human alcohol dehydrogenase (ADH) gene expression, and the physiological and pathological consequences of alterations in ADH expression. We hypothesize that differences in the expression of the ADH genes affect the metabolism of alcohol, the risk for alcoholism and the physiological and pathological consequences of alcohol consumption. To begin testing this hypothesis we will identify the regions that control ADH expression, identify polymorphisms in these regions, and then analyze whether these polymorphisms affect gene expression.We will identify cis-acting elements important in the regulation of the human ADH genes, with primary focus on the class I genes and ADH7. These have different patterns of expression, and produce enzymes that influence important metabolic processes including metabolism of ethanol and retinol. Cis-acting elements will be identified by a combination of functional studies (transfections) and protein-binding analyses (DNaseI footprinting and gel retardation). We will identify transcription factors that bind to these sequences. The ADH genes are clustered on chromosome 4, and we hypothesize that distant flanking sequences are important in regulating this group of genes. We will test this hypothesis by studying more distant sequences, extending at least 10 kb from the coding regions. We will also analyze the regulation of large chromosomal segments (BACs) carrying groups of ADH genes to detect potential interactions in a chromosomal context. We hypothesize that inter-individual differences in regulatory sequences cause differences in ADH gene expression. We will identify and characterize polymorphisms in the regulatory regions and test their effects on gene expression in vitro. These two aims will be closely coupled, with the localization of cis-acting elements directing our search for polymorphisms, and our detection of functional polymorphisms helping to prioritize further study of the cis-acting elements.These studies will contribute to our understanding of the genetic factors underlying differences among individuals in the metabolic, pharmacological and pathological effects of alcohol consumption. They will also increase our basic understanding of gene regulation.