Role of the extracellular matrix during Wolffian/epididymal duct morphogenesis

项目摘要 附睾提供了一个独特的管腔流体微环境，允许精子成熟和存活， 这种功能的破坏会导致男性不育。此外，还可能出现附睾功能的破坏 由于胎儿发育异常，虽然很少有人知道沃尔夫的过程， 导管/附睾发育或导致男性不育的先天性缺陷的性质和原因。的 本申请的中心假设是沃尔夫氏管的伸长和卷曲对于 由此产生的附睾的功能，以及不能伸长和卷曲导致男性不育。 总体目标是双重的，检查：（a）细胞移动以延长导管的机制和（B） 来剖析调节这些细胞运动的潜在细胞和分子机制。虽然我们 有证据表明，上皮细胞通过插入移动，我们将测试的假设，插入型 围绕导管的间充质细胞的运动和间充质细胞的增强运动 导管中的细胞有助于导管的伸长和卷曲。一种基因改造的老鼠， 先进的显微镜，包括共聚焦，二次谐波双光子，和原子力显微镜，在体外 器官培养和现代软件分析将被用来检验下面概述的假设 三个具体目标：（1）检验ECM的刚度（模量）经历动态变化的假设， 在沃尔夫氏管形态发生期间的变化，从而提供生物力学环境， 上皮细胞和间充质细胞的嵌入以及间充质细胞在组织内的增强运动。 interstitium. (2)为了验证间充质细胞的径向嵌入和细胞团 间充质细胞在胼胝体内的运动是沃尔夫管伸长的主要驱动力， 盘绕。(3)为了验证Ptk 7和Rac 1调节放射状嵌入和整体运动的假设 间充质细胞通过改变其沉积来调节ECM生物力学特性， 在沃尔夫氏管发育过程中的组装，这反过来又对男性生育力很重要。因此本 应用集中于ECM在沃尔夫管形态发生期间的作用，特别注意 它的组装，分布和刚度的重要性，以及如何协调，以调节内外侧和 上皮细胞和间充质细胞分别呈放射状嵌入， 间充质细胞在胎盘内。这些事件的协调对于Wolffian/附睾管至关重要 发展，因此，男性生育能力。这项研究的预期成果不仅将有一个重大的 对生殖生物学的一个领域的影响，一直知之甚少，但也将有助于我们的 了解肾小管形态发生的基本过程。具体来说，他们将提供一个 了解附睾在发育过程中的生长调节在临床上是重要的。

PROJECT SUMMARY The epididymis provides a unique luminal fluid microenvironment that allows for sperm maturation and survival, and disruptions to this function lead to male infertility. Further, disruptions to epididymal function may also arise as a consequence of abnormal fetal development, although very little is known either of the process of Wolffian duct/epididymal development or of the nature and causes of congenital defects that lead to male infertility. The central hypothesis of this application is that elongation and coiling of the Wolffian duct is crucial for the function of the resulting epididymis, and that failure to elongate and coil leads to male infertility. The overall goal is two-fold, to examine: (a) the mechanisms by which cells move to elongate the duct and (b) to dissect the underlying cellular and molecular mechanisms that regulate those cell movements. Although we have evidence that epithelial cells move by intercalating, we will test the hypothesis that intercalation-type movements of the mesenchyme cells that surround the duct and the en masse movement of mesenchymal cells in the interstitium contribute to ductal elongation and coiling. A combination of genetically modified mice, advanced microscopy including confocal, second harmonic two-photon, and atomic force microscopy, in vitro organ culture and contemporary software analyses will be used to test the hypotheses outlined in the following three specific aims: (1) To test the hypothesis that the stiffness (modulus) of the ECM undergoes dynamic changes during Wolffian duct morphogenesis thereby providing a biomechanical environment that promotes epithelial and mesenchymal cell intercalation and en masse movement of mesenchymal cells within the interstitium. (2) To test the hypothesis that radial intercalation of mesenchymal cells and the en mass movements of mesenchymal cells within the interstitium are major drivers of Wolffian duct elongation and coiling. (3) To test the hypothesis that Ptk7 and Rac1 regulate radial intercalation and en masse movement of mesenchymal cells via regulating ECM biomechanical properties through changes in its deposition and assembly during Wolffian duct development, which in turn are important for male fertility. Therefore, this application focuses on the role of the ECM during Wolffian duct morphogenesis paying special attention to the importance of its assembly, distribution and stiffness, and how this is coordinated to regulate mediolateral and radial intercalation of epithelial and mesenchymal cells respectively, and the en masse movement of mesenchymal cells within the interstitium. Coordination of these events is critical for Wolffian/epididymal duct development, and therefore, male fertility. The anticipated outcomes of this study will not only have a major impact on an area of reproductive biology that has been poorly understood, but will also contribute to our understanding of the fundamental process of tubular morphogenesis. Specifically they will provide an understanding as to how the regulation of growth of the epididymis during development is important clinically.