Embryonic Development of the Mammalian Epididymis

哺乳动物附睾的胚胎发育

• 批准号: 8442925
• 负责人: Barry T. Hinton
• 金额: $ 29.96万
• 依托单位: UNIVERSITY OF VIRGINIA
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-04-01 至 2017-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8442925
• 关键词: Actins; Apical; Apoptosis; Area; Cell Polarity; Cell Proliferation; Cell Shape; Cell division; Cells; Cochlea; Congenital Abnormality; Cytoskeleton; DNA Sequence Rearrangement; Defect; Development; Duct (organ) structure; Ductal; Embryo; Embryonic Development; Epididymis; Event; Failure; Fertility; Fetal Development; Gene-Modified; Goals; Growth; Imaging Techniques; Individual; Lead; Liquid substance; Male Infertility; Molecular; Morphogenesis; Mus; Nature; Neural Tube Development; Neural tube; Organ; Organ Culture Techniques; Outcome; Outcome Study; Pathway interactions; Play; Polycystic Kidney Diseases; Positioning Attribute; Process; Regulation; Reproductive Biology; Role; Sperm Maturation; Structure of mesonephric duct; Testing; Time; Tube; cell motility; gastrulation; innovation; intercalation; interest; kidney cell; male; member; nephrogenesis; novel; public health relevance; rho

DESCRIPTION (provided by applicant): The epididymis is critical to the process of sperm maturation because it provides a unique luminal fluid microenvironment that allows for sperm maturation and survival, and disruptions to this function lead to male infertility. However, disruptions to epididymal function may also arise as a consequence of abnormal fetal development, although very little is known either of the process of epididymal development or of the nature and causes of congenital defects that lead to male infertility. A major event during Wolffian/ epididymal duct embryonic development is elongation and coiling, presumably as a result of cell proliferation. However, in this application we hypothesize that an additional mechanism, cell intercalation contributes to elongation and coiling. Elongation and coiling is not a trivial event but must be highly coordinated with its specialized function of providing a unique luminal fluid microenvironment that is so important for sperm maturation. We have chosen the embryonic time period because cell proliferation and ductal coiling are initiated and it is a time when potential defects can occur. Examining the mechanism(s) of cell intercalation as a means to elongate and coil the Wolffian duct is novel, and we are especially interested in examining the contribution of a member of the planar cell polarity pathway (PCP), Ptk7, as a regulator of this important event during Wolffian duct morphogenesis. A combination of genetically modified mice, modern imaging techniques, in vitro organ culture techniques, and gene modifying approaches will be used to test the hypotheses outlined in the following three specific aims: (1) To test the hypothesis that Ptk7 plays an important role in cell shape and cell positioning, which in turn allow the Wolffian duct to undergo the morphogenic events of elongation and coiling. (2) To test the hypothesis that Ptk7 regulates specific cell rearrangements by modulating the basolateral protrusive activity and the orientation of cell division yet maintaining cell proliferaion during Wolffian duct embryonic development. (3) To test the hypothesis that cell intercalation during Wolffian duct elongation and coiling is driven by polarized changes in cytoskeleton organization, and is regulated by Ptk7 through activation of the Wnt/PCP pathway. In summary, the hypothesis that the Wolffian duct can elongate via cell intercalation is highly novel and innovative because it has always been assumed that elongation of the epididymal duct is via cell proliferation only. In addition, we have uncovered an unusual regulatory molecule, Ptk7, which is hypothesized to play a role in Wolffian duct elongation and coiling. 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 tube morphogenesis. Specifically they will provide an understanding as to how the regulation of growth of the epididymis during development is important clinically.

描述（由申请人提供）：附睾对于精子成熟过程至关重要，因为它提供了独特的管腔液体微环境，使精子成熟和存活，而该功能的破坏会导致男性不育。然而，胎儿发育异常也可能导致附睾功能受损，尽管人们对附睾发育过程或导致男性不育的先天缺陷的性质和原因知之甚少。沃尔夫/附睾管胚胎发育过程中的一个主要事件是伸长和卷曲，可能是细胞增殖的结果。然而，在本申请中，我们假设一种额外的机制，即细胞嵌入有助于伸长和卷曲。伸长和卷曲不是一件小事，但必须与其提供独特的管腔液体微环境的特殊功能高度协调，这对精子的成熟非常重要。我们选择胚胎时期是因为细胞增殖和导管卷曲开始，并且这是可能发生潜在缺陷的时期。检查细胞嵌入的机制作为拉长和卷曲沃尔夫管的一种手段是新颖的，我们特别感兴趣的是检查平面细胞极性途径（PCP）成员 Ptk7 作为调节剂的贡献沃尔夫管形态发生过程中的这一重要事件。结合转基因小鼠、现代成像技术、体外器官培养技术和基因修饰方法，将用于检验以下三个具体目标中概述的假设：（1）检验Ptk7在细胞形状和细胞定位，这反过来又使沃尔夫管经历伸长和卷曲的形态发生事件。 (2)检验Ptk7在沃尔夫管胚胎发育过程中通过调节基底外侧突出活性和细胞分裂方向并维持细胞增殖来调节特定细胞重排的假设。 (3) 检验以下假设：沃尔夫管伸长和卷曲过程中的细胞嵌入是由细胞骨架组织的极化变化驱动的，并由 Ptk7 通过激活 Wnt/PCP 途径进行调节。总之，沃尔夫管可以通过细胞嵌入伸长的假设是非常新颖和创新的，因为人们一直认为附睾管的伸长仅通过细胞增殖来实现。此外，我们还发现了一种不寻常的调节分子 Ptk7，假设它在沃尔夫导管伸长和卷曲中发挥作用。这项研究的预期结果不仅会对人们知之甚少的生殖生物学领域产生重大影响，而且还将有助于我们了解管形态发生的基本过程。具体来说，他们将让人们了解发育过程中附睾生长的调节在临床上的重要性。