BIOLOGY OF THE UTERINE OXYTOCIN RECEPTOR

分娩障碍目前构成了唯一最重要的 儿童健康问题。 事实上，据估计，早产 仅这一项就占围产期发病率的75%以上， 死亡率每年都在这个国家。 的长期目标 本申请旨在阐明分娩的机制， 在孕妇中开始，并制定方法， 过早开始分娩。 本提案的具体目标 旨在定义细胞和分子机制， 一种被充分表征的激素催产素调节子宫收缩力。 我们建议分离和纯化子宫催产素受体， 产生针对所述受体的高亲和力多克隆抗体， 受体功能的生物化学、形态学和分子分析。 利用生物化学和免疫电镜技术， 应定义受体的细胞生命周期，包括其 生物合成、加工、细胞内运输和膜拓扑学 我们将定义催产素结合的动力学和药理学， 信号转导和降解。 我们还建议克隆 子宫催产素受体，从而确定受体序列， 分子结构 我们将在哺乳动物中表达克隆的受体 并使用定点突变来定义分子 受体结构和功能的解剖学， 受体细胞生物学的分子细节。 最后，我们将使用 受体克隆以鉴定表达催产素的细胞类型 受体在妊娠子宫和阐明的机制， 受体基因在妊娠和分娩过程中的表达。 这些研究的数据应该可以让我们建立一个工作模型 影响子宫收缩力的基本机制 催产素 结合其他激素的新信息， 调节子宫收缩力的药物，我们预计这项工作将 使我们更清楚地了解人类分娩的生物学， 允许制定合理的科学方法， 早产

Disorders to parturition currently constitute the single most important problem in child health. Indeed, it is estimated that preterm labor alone accounts for greater than 75% of the perinatal morbidity and mortality seen in this country each year. The long-term objectives of this application are to elucidate the mechanisms by which labor is initiated in pregnant women and to develop methods to prevent the premature initiation of parturition. The specific aims in this proposal are intended to define the cellular and molecular mechanism s by which a well-characterized hormone, oxytocin, mediates uterine contractility. WE propose to isolate and purify the uterine oxytocin receptor and to generate high-affinity polyclonal antibodies to the receptor for use in biochemical, morphological and molecular analysis of receptor function. Using both biochemical and immunoelectron microscopic techniques we shall define the cellular life cycle of the receptor including its biosynthesis, processing, intracellular traffic and membrane topology and we shall define the kinetics and pharmacology of oxytocin binding, signal transduction and degradation. We further propose to clone the uterine oxytocin receptor and thus determine the receptor sequence and molecular structure. We shall express the cloned receptor in mammalian fibroblasts and use site-directed mutagenesis to define the molecular anatomy of receptor structure and function and to characterize the molecular details of receptor cell biology. Finally, we shall use the receptor clones to identify the cell-type(s) expressing the oxytocin receptor in the gravid uterus and to elucidate the mechanisms of receptor gene expression in the uterus during gestation and parturition. The data from these studies should allow us to construct a working model of the basic mechanisms by which uterine contractility influenced by oxytocin. Taken together with new information on other hormones and agents mediating uterine contractility we anticipate that this work will lead to a clearer understanding of the biology of human parturition and allow the development of rationale scientific methods to prevent premature labor.