DEFECTS IN MULLERIAN DUCT REGRESSION

在狗的两种不同的遗传综合征中，苗勒氏二重奏 坚持存在睾丸组织：XX性反转和 持续性苗勒管综合征(PMDS)。这是唯一的 具有一致和特定遗传缺陷的已知动物模型 在对迄今为止描述的穆勒管道系统的压制中。 保存这些模型以供进一步研究完全取决于 根据这项提议，由于没有其他资金可供维持 这些动物。它们的意义不仅在于它们是 人类发育障碍的模型。他们是一个重要的 了解苗勒氏抑制作用的资源 哺乳动物生殖发育和功能中的物质(MIS)。 虽然目前已克隆和生化了管理信息系统的基因 其作用机制已被提出，其受体已 没有被确认身份。这些模型应该会导致更详细的 对基因控制、结构和机制的理解 管理信息系统的作用。在这两种综合征中，我们都已经证明了 穆勒回归不太可能是由于没有管理信息系统而导致的 因为我们最近发现受影响的睾丸组织 狗导致胚胎大鼠器官中米勒管的退化 培养生物测定。我们这项研究的目标是 确定穆勒式的明显不敏感 系统转到管理信息系统是由于管理信息系统的时间或数量上的缺陷。 分泌物或与MIS受体的缺陷有关。这些假设 将通过以下方式进行测试：1)确定是否合成和定时 感染犬的MISmRNA和MIS值与正常组相当 正常雄性产仔，以及2)比较位置， MISR的浓度和结合特性的研究 在受影响的狗和正常的产仔犬身上。 患有XX性反转(可卡犬)和经前综合症(迷你型)的狗 将通过培育已知的这些携带者来生产 常染色体隐性性状。生产和蜂窝定位 正常和患病仔鼠睾丸中的Mis mRNA将是 用Northern印迹、原位杂交等方法进行定量比较， 和免疫组织化学技术。正常人群睾丸组织中的Mis水平 和受影响的窝产仔将通过蛋白质印迹法确定 分析。MLS受体将首先通过以下方式鉴定 抗独特型抗体，随后通过结合 稳定细胞系产生代谢标记的管理信息系统 将重组人MIS1基因导入小鼠体内。

In two separate hereditary syndromes in the dog, Mullerian duets persist in the presence of testicular tissue: XX sex reversal and the persistent Mullerian Duct Syndrome (PMDS). These are the only known animal models with consistent and specific inherited defects in repression 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 have been proposed, the MIS receptor has not been identified. These models should lead to a more detailed understanding of the genetic control, structure, and mechanisms of action of MIS. In both syndromes, we have shown that failure of Mullerian regression is unlikely to result from an absence of MIS since we have recently shown that testicular tissue of affected 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 insensitivity of the Mullerian system to MIS is due to a defect in timing or amount of MIS. secretion or to a defect in the MIS receptor. These hypotheses will be tested by: 1) Determine whether the synthesis and timing of MIS mRNA and MIS in affected dogs is comparable to that in normal male littermates, and 2) Comparing the location, concentration, and MIS binding characteristics of the MIS receptor in affected dogs and normal littermates. Dogs with XX sex reversal (Cocker Spaniels) and PMDS (Miniature Schnauzers) will be produced by breeding known carriers of these autosomal recessive traits. Production and cellular location of MIS mRNA in testes of normal and affected littermates will be quantitated and compared by Northern blot, in situ hybridization, and immunohistochemical techniques. MIS levels in testes of normal and affected littermates will be determined by Western blot analysis. The MlS receptor will first be identified by antiidiotypic antibodies and subsequently by binding to metabolically-labelled MIS produced by stable cell lines transfected with the recombinant human MIS gene.