MOLECULAR BIOLOGY OF THE MENKES SYNDROME GENE

描述：铜是原核生物和 真核细胞 它的氧化潜力是正常的 超过30种已知酶在电子传递中的功能， 神经递质、结缔组织和自由基清除系统。 然而，虽然铜是生命所必需的，但它在存在时具有高度毒性 过量。 因此，生物体已经进化出精确的机制， 调节铜稳态。 然而，人们对它知之甚少。 哺乳动物的基因来调节这种微妙的平衡。 理解本 基因的克隆大大增强了这一复杂过程， 两种遗传性疾病，门克斯病和威尔逊病， 分布不均是主要的代谢缺陷。 两者都被发现是 与P-型具有强同源性的铜结合跨膜ATP酶 细菌的ATP酶，并在库珀运输中起作用。 于本 项目期间，克隆了门克斯病基因（ATP 7A;MNK）， 人们开始研究它的结构、功能和在铜中的作用 体内平衡 在发现该基因后， MNK基因的结构已被确定，并发现非常相似 与Wilson病基因（ATP 7 B; WND）的同源性。 MNK蛋白已经被 通过免疫荧光定位于高尔基体网络。 此外该 同源小鼠基因已经被克隆出来，并被用来证明斑驳的 突变小鼠为门克斯氏病的研究提供了有价值的动物模型 疾病 在这种应用中，研究建议扩展 MNK基因及其蛋白产物的表征，并鉴定 哺乳动物中参与铜稳态的新相关基因。 具体 目的：（1）证实MNK的细胞内定位 在正常和铜负载条件下通过电子显微镜观察蛋白质; (2)进行一项比较研究， 正常和突变小鼠MNK和WND基因的表达;（3）利用 用于分析结构组分的MNK基因的表达构建体 参与表达、铜通道和蛋白定位;和（4） 鉴定和分离与铜转运相关的新基因， 在哺乳动物细胞中的稳态。 这些研究将以取得的进展为基础， 在过去的5年里，将大大增加对 哺乳动物的铜稳态和MNK基因在这种平衡中的作用 以及门克斯氏病

DESCRIPTION: Copper is an essential trace element in both prokaryotic and eukaryotic cells. Its oxidative potential is required for the normal function of over 30 known enzymes in the electron transport, neurotransmitter, connective tissue and free-radical scavenger systems. However, while copper is essential for life, it is highly toxic when present in excess. Therefore, organisms have evolved exact mechanisms for regulating copper homeostasis. Little is known, however, about the mammalian genes that regulate this fine balance. The understanding of this complex process has been greatly enhanced by the cloning of genes causing two genetic disorders, Menkes and Wilson's diseases, in which copper maldistribution is the major metabolic defect. Both have been found to be copper-binding transmembrane ATPases with strong homology to the P-type ATPases of bacteria and to function in cooper transport. During the current project period, the gene (ATP7A;MNK) for Menkes disease was cloned and studies were begun to investigate its structure, function and role in copper homeostasis. Among the findings since identifying the gene, the basic structure of the MNK gene has been determined and found to be very similar to that of the Wilson s disease gene (ATP7B; WND). The MNK protein has been localized to the Golgi network by immunofluorescence. In addition, the homologous mouse gene has been cloned and used to show that the mottled mouse mutants provide valuable animal models for the study of Menkes disease. In this application, studies are proposed to extend characterization of the MNK gene and its protein product and to identify novel related genes involved in copper homeostasis in mammals. Specific aims are: (1) to demonstrate the intracellular localization of the MNK protein by electron microscopy under normal and copper loading conditions; (2) to perform a comparative study of the developmental expression patterns of the MNK and WND genes in normal and mutant mice; (3) to utilize expression constructs of the MNK gene for analysis of structural components involved in expression, copper channeling and protein localization; and (4) to identify and isolate novel related genes involved in copper transport and homeostasis in mammalian cells. These studies will build upon progress made over the past 5 years and will significantly add to the understanding of copper homeostasis in mammals and the role of the MNK gene in this balance and in Menkes disease.