MOLECULAR STUDIES OF MONOAMINE OXIDASES

本项目的总体目标是了解 两种单胺氧化酶（MAO A和B）的分子基础， 基因水平。 单胺氧化酶（MAO）是儿茶酚胺的重要酶 新陈代谢. 异常水平的单胺氧化酶活性已显示在一个 精神障碍的数量。 用全长人肝毛 本实验室克隆的A和B cDNA， 并研究这些基因的表达。 这些 研究对基础和临床研究都很重要。 这个为期五年的研究科学家奖的具体目标 应用如下所述。 使用已建立的细菌 和哺乳动物细胞表达质粒载体， 肝MAO A和B cDNA将被表达，并且催化 将表征所表达蛋白质的性质。 以单胺氧化酶A和B cDNA为探针进行北方印迹分析， 这些基因表达之间的相关性， 各种人体组织中的mRNA、蛋白质和催化活性 将被审查。 这项研究将表明， MAO A和B的特异性被控制在 转录或翻译。 使用Southern印迹分析， 细胞含有人类染色体-小鼠DNA杂交以及 原位杂交技术对人肝单胺氧化酶的染色体定位 将确定A和B基因。 这些基本知识是 对于研究MA 0基因在精神障碍中的作用至关重要。 将分析MAO A和B的基因组DNA。 几种人 将使用MAO筛选基因组文库（cosmic和LAMBDA） A和B cDNA探针，编码人肝MAO A的基因组DNA 克隆B基因。 基因组的限制性图谱 然后构建MAO A和B克隆。 此外，MAO A 通过链终止法对B基因进行测序， 将分析它们的启动子区。 将研究MAO A和B的异质性。 MAO A、B 相关的cDNA将从其他人体组织中克隆出来， 将比较它们的DNA和氨基酸序列。 因此 不同组织中单胺氧化酶A（或B）的异同 将被清楚地理解。 这些信息将提供一个 关于使用血小板单胺氧化酶B作为 脑MAO B的标记物，并将对 未来的临床研究

The overall objective of this project is to understand the molecular basis of two types of monoamine oxidase (MAO A and B) at the gene level. MAO is an important enzyme in catecholamine metabolism. Abnormal levels of MAO activity have been shown in a number of mental disorders. With the full-length human liver MAO A and B cDNAs cloned in this laboratory, the genomic organizations and the expressions of these genes will be investigated. These studies have great importance for both basic and clinical research. The specific aims of this five-year Research Scientist Award application are described below. Using the established bacterial and mammalian cell expression plasmid vectors, the cloned human liver MAO A and B cDNAs will be expressed and the catalytic properties of the expressed proteins will be characterized. Using Northern blot analysis with MAO A and B cDNA as probes, the correlation among the expressions of these genes at the levels of mRNA, protein and catalytic activities in various human tissues will be examined. This study will indicate whether the tissue specificity of MAO A and B is controlled at the level of transcription or translation. Using Southern blot analysis of cells containing human chromosomes - mouse DNA hybrid as well as in situ hybridization, the chromosomal location of human liver MAO A and B genes will be determined. This fundamental knowledge is essential for studying the role of MA0 genes in mental disorders. The genomic DNAs For MAO A and B will be analyzed. Several human genomic libraries (cosmic and LAMBDA) will be screened using MAO A and B cDNA probes, the genomic DNAs encoding human liver MAO A and B genes will be cloned. The restriction maps of the genomic MAO A and B clones will then be constructed. Further, the MAO A and B genes will be sequenced by the chain termination method, and their promoter regions will be analyzed. The heterogeneity of MAO A and B will be investigated. MAO A, B and related cDNAs will be cloned from other human tissues, and their DNA and amino acid sequences will be compared. Thus, the similarities and differences of MAO A (or B) from various tissues will be clearly understood. This information will provide a conclusive answer on the validity of using platelet MAO B as a marker for brain MAO B and will have significant implications on future clinical studies.