In vivo role of BTK-mediated inhibition of Wnt/b-catenin signaling during hematop

描述（由申请人提供）：目前我正在使用化学遗传学，siRNA筛选和基于质谱的蛋白质组学来探测Wnt/b-catenin信号通路。利用这些技术，我们确定了Tec激酶是Wnt/b-连环蛋白信号传导的负调节因子。由于Tec激酶BTK的突变是导致x连锁无球蛋白血症的原因，我们试图在B细胞中证实我们的原始发现。我们发现Tec激酶在培养的B细胞中也负向调节Wnt/ B -catenin信号。这项工作使我提出了Tec激酶和Wnt信号传导的相互作用将在体内造血中发挥重要作用的假设。我申请独立之路奖是为了延长我的博士后培训，学习疾病和造血的动物模型，学习如何解剖小鼠和采集骨髓，如何进行小鼠骨髓移植实验，如何用流式细胞术分析这些实验。正如提案中概述的那样，我将使用所有这些方法来验证我的假设。作为一名独立研究者，我计划利用我在蛋白质组学和造血交叉领域的独特地位，探索细胞分化过程中信号转导的分子机制。这个方向不仅可以让我充分利用我所学到的知识，还可以让我进入一个具有重要临床意义的领域，比如脐带血移植、骨髓移植和癌症治疗。

DESCRIPTION (provided by applicant): Currently I am using chemical genetics, siRNA screens and mass spectrometry- based proteomics to probe the Wnt/b-catenin signaling pathway. Using these techniques we identified Tec kinases as negative regulators of Wnt/b-catenin signaling. Because mutations in the Tec kinase BTK are responsible for X-linked agammaglobulinemia, we sought to corroborate our original findings in B cells. We found that Tec kinases also negatively regulate Wnt/b-catenin signaling in B cells in culture. This work has led me to the hypothesis that the interplay of Tec kinases and Wnt signaling will have a significant role in hematopoiesis in vivo. I am applying for the Pathway to Independence Award in order to extend my postdoctoral training so that I can learn about animal models of disease and hematopoiesis and gain practical knowledge of how to dissect mice and collect bone marrow, how to perform murine bone marrow transplantation experiments and how to analyze these experiments by flow cytometry. As outlined in the proposal, I will use all of these methods in order to test my hypothesis. As an independent investigator I plan to exploit my unique position at the intersection of proteomics and hematopoiesis to explore the molecular mechanisms of signal transduction in cellular differentiation. Not only would this direction allow me to fully utilize my training to date, it would allow me to enter a field that has important clinical implications, such as cord blood engraftment, bone marrow transplant and cancer treatments. PUBLIC HEALTH RELEVANCE: In addition to testing an interesting basic science hypothesis, the results of this proposal are likely to be relevant to the mission of the NHLBI in two areas: 1) informing clinicians treating patients diagnosed with X-linked agammaglobulinemia to focus attention to Wnt/b-catenin related symptoms such as colorectal carcinoma, and 2) using Tec kinase inhibition to increase the efficacy of human cord blood in clinical engraftment.