Role of Gremlin in embryonic development

描述（由申请人提供）： 这项研究的总体目标是更好地了解发育中的肢体和肾脏的信号事件。骨形态发生蛋白（BMPs）及其拮抗剂在发育过程中的特定模式中非常重要。Gremlin是一种BMP拮抗剂，已被证明在发育胚胎的多个区域表达，并在肢体发育中发挥重要作用。 为了测试Gremlin是否是正确胚胎发育所必需的，产生了靶向突变。 纯合子有两种主要的表型：肢体畸形和肾发育不全。 肢体模式的研究为分子信号网络如何正确产生适当的细胞命运提供了许多见解。肢体中的正确信号的失败导致肢体畸形，这是一种常见的先天性畸形。为了研究Gremlin突变小鼠的肢体畸形，将分析一系列分子标记的基因表达变化。体外肢体培养中的过度表达分析将解决Gremlin与其他图案分子的关系。 在另一组实验中，将研究肾发育不全的原因。首先，仔细分析分子标记物将试图准确地确定缺陷在肾发生中发生的位置和时间。后肾间充质和输尿管芽的体外培养物将确定哪些组织需要Gremlin，并进一步测试Gremlin作用的机制。 申请人是一名临床科学家，拥有儿科认证，目前隶属于UCSF医学中心儿科系。他在儿科科学家发展计划资助的支持下启动了这个项目，并打算在这个应用程序的支持下完成对Gremlin突变体的分析。这项研究将在理查德M.加州大学伯克利分校的哈兰德领导着一个实验室，该实验室利用多模型系统来更好地了解脊椎动物的发育。这项研究将为小鼠靶向突变的分析以及蛋白质生物化学提供重要的培训，这对申请人成为独立研究者至关重要，这是他的长期目标。

DESCRIPTION (provided by applicant): The overall goal of the proposed research is to better understand the signaling events that pattern the developing limb and kidney. The Bone Morphogenetic Proteins (BMPs) as well as their antagonists are important in specifying pattern during development. Gremlin is a BMP antagonist that has been shown to be expressed in multiple regions of the developing embryo and appears important in limb development. In order to test whether Gremlin was required for correct embryonic development, a targeted mutation was generated. Homozygotes have two main phenotypes: limb malformation and renal agenesis. The study of limb patterning has provided many insights into how molecular signaling networks might act to correctly produce appropriate cell fate. The failure of correct signaling in the limb results in limb results in limb anomalies, a common congenital malformation. To study the limb malformations in Gremlin mutant mice, an array of molecular markers will be analyzed for changes in gene expression. Over expression analysis in in vitro limb cultures will address Gremlin's relationship with other patterning molecules. In another set of experiments, the cause of the renal agenesis will be investigated. First, careful analysis of molecular markers will attempt to define exactly where and when the defect occurs in nephrogenesis. In vitro cultures of metanephric mesenchyme and ureteric buds will define in which tissue Gremlin is required and further test the mechanism of Gremlin action. The applicant is a clinician scientist who is board certified in Pediatrics and is currently affiliated with the Department of Pediatrics at UCSF Medical Center. He has initiated this project with support from the Pediatric Scientist Development Program grant and intends to complete the analysis of the Gremlin mutant with support from this application. The research will be conducted in the laboratory of Richard M. Harland at UC-Berkeley who heads a laboratory that utilizes multiple model systems to better understand vertebrate development. The research proposed will provide important training in the analysis of targeted mutations in the mouse as well as protein biochemistry which will prove crucial for the applicant when he becomes an independent investigator, his long-term goal.