Wnt-10A and Thyrotrope Cells

描述（由候选人提供）： Wnt信号在正常和异常垂体功能中的基础科学是令人兴奋的内分泌学研究领域。这项研究的目的是表征Wnt-10A对促甲状腺细胞的影响。利用小鼠TtT-97促甲状腺肿瘤模型的增生，我以前证明，治疗TtT-97肿瘤与甲状腺激素减少肿瘤大小与Wnt-10A配体的表达减少。这项拨款提案的目的是阐明Wnt-10A在促甲状腺激素中的作用，具体而言：1）表征Wnt-10A对Wnt信号传导、细胞周期基因和促甲状腺细胞生长的影响，2）鉴定调节TtT-97细胞中Wnt-10A表达的顺式作用启动子元件，3）建立Wnt-10A表达的垂体定位和体内甲状腺激素反应性; 4）阐明Wnt-10A过表达对促甲状腺细胞的影响。为了更好地表征调节Wnt-10A基因表达的因素，将比较调节的（TtT-97）和未调节的（α-TSH）促甲状腺细胞生长的模型系统。 为了实现这些科学目标，将进行利用Wnt-10A功能丧失和过度表达的研究方法。具体而言，siRNA技术将用于研究Wnt-10A敲低对TtT-97和α-TSH细胞中细胞周期基因和生长的影响。接下来，将进行Wnt-10A过表达研究，以表征Wnt信号传导途径和被Wnt-10A激活的细胞周期基因，并进一步确定重要的调控元件。进一步的研究，然后提出定义的Wnt-10A启动子，调节基础活动和甲状腺激素的反应性的顺式作用元件。为了建立Wnt-10A在小鼠垂体中的促甲状腺激素定位及其甲状腺激素反应性，然后提出原位杂交研究。最后，为了确定Wnt-10A过表达对促甲状腺细胞的体内影响，提出了转基因小鼠模型。 这项基础研究的主要目标是促进对促甲状腺细胞生理学的理解。主要研究者Janice Kerr是一名医生，博士后研究员，致力于基础科学研究和学术医学事业。主要研究者的短期目标是提高她在分子生物学和Wnt信号传导领域的研究技能。她的长期目标是成为内分泌学领域训练有素的独立科学家。 这项研究与公共卫生有关，因为Wnt信号传导是正常发育和人类恶性肿瘤中公认的因素，进一步了解Wnt-10A可能会阐明其在正常和异常垂体过程中的作用。

DESCRIPTION (provided by candidate): The basic science of Wnt signaling in normal and abnormal pituitary gland function is an area of exciting endocrinology research. The goal of this research proposal is to characterize the effects of Wnt-10A on thyrotrope cells. Utilizing the murine TtT-97 thyrotropic tumor model of hyperplasia, I previously demonstrated that treatment of TtT-97 tumors with thyroid hormone reduced tumor size in association with decreased expression of the Wnt-10A ligand. The purpose of this grant proposal is to elucidate the role of Wnt-10A in thyrotropes, specifically: 1) to characterize the effects of Wnt-10A on Wnt signaling, cellcycle genes, and growth in thyrotrope cells, 2) to identify the cis-acting promoter elements that regulate Wnt-10A expression in TtT-97 cells, 3) to establish the pituitary localization and thyroid hormone responsiveness of Wnt-10A expression, in vivo, and 4) to elucidate the effects of Wnt-10A over-expression on thyrotrope cells. To better characterize factors that regulated Wnt-10A gene expression, model systems of regulated (TtT-97) and unregulated (alpha-TSH) thyrotrope cell growth will be compared. In order to achieve these scientific objectives, research methods that utilize Wnt-10A loss-of-function and over-expression will be performed. Specifically, siRNA technology will be utilized to study the effects of Wnt-10A knock-down on cell-cycle genes and growth in TtT-97 and alpha-TSH cells. Next, Wnt-10A over- expression studies will then be performed to characterize the Wnt signaling pathway and cell-cycle genes that are activated by Wnt-10A and further define important regulatory elements. Further studies are then proposed to define the cis-acting elements of the Wnt-10A promoter that regulate basal activity and thyroid-hormone responsiveness. To establish the thyrotrope localization of Wnt-10A and its thyroid hormone responsiveness in the murine pituitary gland, in situ hybridization studies are then proposed. Lastly, to determine the in vivo effects of Wnt-10A over-expression on thyrotrope cells, a transgenic mouse model is proposed. The primary goal of this basic research study is to advance the understanding of thyrotrope cell physiology. The principle investigator, Janice Kerr, is a physician, post-doctoral fellow with a strong commitment to basic science research and a career in academic medicine. The short-term goals of the principle investigator are to advance her research skills in the area of molecular biology and Wnt signaling. Her long-term goals are to become a well-trained, independent-scientist in the field of endocrinology. The research proposed is relevant to public health in that Wnt signaling is a well-recognized factor in normal development and human malignancies, and further understanding of Wnt-10A may elucidate its role in normal and abnormal pituitary processes.