DEFECTS IN MULLERIAN DUCT REGRESSION

苗勒管回归缺陷

• 批准号: 3316647
• 负责人: VICKI N MEYERS-WALLEN
• 金额: $ 16.67万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-04-01 至 1995-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3316647
• 关键词: Mullerian duct inhibiting substance; autosomal recessive trait; confocal scanning microscopy; congenital reproductive system disorder; cytogenetics; dogs; electron microscopy; embryo /fetus; genetic regulation; genital secretion; hermaphroditism; histogenesis; histology; in situ hybridization; messenger RNA; molecular pathology; northern blottings; organ culture; pseudohermaphroditism; sex chromosomes; testicular feminization; testis disorder

In two separate hereditary syndromes in the dog, Mullerian ducts persist in the presence of testicular tissue: Persistent Mullerian Duct Syndrome (PMDS) and XX sex reversal (XXSR). These are the only known animal models with consistent and specific inherited defects in regression of the Mullerian duct system described to date. Preservation of these models for further study depends entirely upon this proposal, since there is no other funding to maintain these animals. Their significance is not only that they are models of human developmental disorders. They are an important resource for understanding the role of Mullerian Inhibiting Substance (MIS) in mammalian reproductive development and function. Although the gene for MIS has been cloned and biochemical mechanisms of its action proposed, the MIS receptor (MIS-R) has only been indirectly identified. These models should lead to a more detailed understanding of the genetic control, structure, and mechanism of action of MIS. In both syndromes, we have shown that failure of Mullerian duct regression is unlikely to result from MIS absence, since testicular tissue of affected neonatal dogs causes regression of embryonic rat Mullerian ducts in an organ culture bioassay. Our objective in the present study is to determine whether the apparent resistance of the Mullerian duct system to MIS is due to a defect in timing or amount of MIS secretion or to a defect in the MIS-R. These hypotheses will be tested by: 1) Determining whether the synthesis and timing of MIS and MIS mRNA in affected embryos is comparable to that of normal male littermates, 2) Identifying the MIS- R in normal and affected embryos during the period of Mullerian duct regression, and 3) Comparing the density, location, concentration, and MIS binding characteristics of the MIS-R in affected and normal littermates. Dogs with PMDS and XXSR will be produced by breeding known carriers of these autosomal recessive traits. Production, cellular location, and biological activity of MIS will be compared in testes of normal and affected embryos by immunohistochemical methods and bioassay. Production and cellular location of MIS mRNA in testes of normal and affected littermates will be compared by Northern blot analysis and in situ hybridization. The MIS-R will first be identified in normal embryos by confocal imaging microscopy. Characteristics of the MIS-R in affected and normal embryos will be compared by competitive binding studies with radiolabeled recombinant human MIS and radiolabeled antiidiotypic antibodies.

在狗的两种不同的遗传综合征中，苗勒管持续存在。 睾丸组织存在：持续性苗勒管综合征 (PMDS)和XX性反转(XXSR)。这是唯一已知的动物 回归中具有一致性和特定遗传缺陷的模型 迄今为止所描述的穆勒风管系统。保存这些东西 进一步研究的模型完全取决于这一建议，因为有 没有其他资金来维持这些动物。它们的意义并不是 只知道它们是人类发育障碍的模型。他们是一个 了解苗勒氏抑制作用的重要资源 哺乳动物生殖发育和功能中的物质(MIS)。 虽然目前已克隆出与管理信息系统有关的基因，并对其生化机制进行了研究。 其作用被提出后，管理信息系统受体(MIS-R)只是间接地 确认身份。这些模型应该会导致更详细的理解 对管理信息系统的遗传控制、结构和作用机制的研究。在……里面 这两个综合征，我们已经表明失败的苗勒管回归 不太可能是由于缺乏管理信息系统造成的，因为睾丸组织 受感染的新生犬导致胚胎大鼠苗勒管退化 在器官培养生物化验中。我们这项研究的目标是 确定米勒风管系统的表观阻力是否 对管理信息系统来说，是由于管理信息系统分泌的时间或数量有缺陷，或者是由于 管理信息系统的缺陷--R。这些假设将通过以下方式进行检验：1)确定 受影响胚胎中MISs和MISmRNAs的合成和时机 可与正常雄性产仔相媲美，2)识别MIS. 苗勒管时期正常胚胎和病变胚胎中的R 回归，以及3)比较密度、位置、浓度和 受影响和正常的管理信息系统-R的MIS结合特性 一窝产仔。患有PMDS和XXSR的狗将通过已知的育种方式生产出来 这些常染色体隐性性状的携带者。生产，蜂窝 将比较管理信息系统的定位和生物活性。 用免疫组织化学方法和生物测定方法检测正常胚胎和病变胚胎。 正常和正常睾丸组织中MISmRNA的产生和细胞定位 受影响的窝产仔将通过Northern杂交分析和 原位杂交。MISR将首先在正常胚胎中被鉴定 通过共聚焦成像显微镜。受影响的管理信息系统-R的特点 正常胚胎将通过竞争性结合研究与 放射性标记重组人管理信息系统及放射性标记抗独特型药物 抗体。