Activation and Signaling Mechanism of the RET Tyrosine Kinase Receptor

描述（申请人提供）：该奖学金将支持波士顿大学Adrian Whitty教授实验室的一名研究生的研究目标和培训。许多形式的癌症是由生长因子（GF）受体的异常信号引起的。因此，对GF受体激活和功能的进一步了解将继续促进癌症治疗方法的改进。然而，关于GF受体激活和信号传导的分子机制的许多基本问题仍未得到解答。我们建议以转染过程中多组分重排（RET）受体为例，开发GF受体信号转导定量机制研究的新方法。RET是一种受体酪氨酸激酶，是神经营养因子家族神经营养因子的受体。RET信号的失调与多种类型的癌症有关，包括多发性内分泌肿瘤（MEN） 2A和-2B、甲状腺髓样癌、甲状旁腺增生和嗜铬细胞瘤。我们提出通过以下三个目标来表征RET激活和信号转导的分子机制：1)利用遗传编码荧光共振能量转移（FRET）构建一个报告系统，利用流式细胞术监测活细胞表面的RET关联事件。2)在Aim 1中开发的FRET报告结构将用于解决有关活细胞上RET激活机制的关键问题。这些问题包括解决关于GF受体是通过配体诱导的受体二聚化，还是通过在预相关受体二聚体或低聚体中引起结构重排而起作用的困难和长期存在的不确定性。3)探讨RET与血管内皮生长因子受体2 （VEGFR2）之间串扰的机制和影响，以确定RET信号串扰发生在什么水平，以及对RET功能的影响如何依赖于VEGFR2刺激水平。总的来说，这三个目标将建立新的方法来阐明GF受体的激活机制，并将建立两个不同的GF受体家族之间串扰的机制和影响。这项研究将帮助她实现她的职业目标，即领导一个学术研究小组，研究与人类健康有关的重要生物学问题。她计划通过在分子、细胞和体内系统复杂性水平上的工作来解决这些问题，主要采用假设驱动和（适当时）定量的观点。研究生阶段的培训计划将使她能够专注于培养自己在分子和细胞方法方面的知识和能力，并在合适的实验室进行博士后研究，从而涵盖在体内的技术和观点。候选人和她的赞助商一起制定了一个非常有效的计划，以实现她需要的培训，以实现她的长期职业目标。

DESCRIPTION (provided by applicant): This fellowship will support the research aims and training of a graduate student in the laboratory of Professor Adrian Whitty at Boston University. Many forms of cancer are caused by aberrant signaling of growth factor (GF) receptors. Consequently, achieving an improved understanding of GF receptor activation and function continues to give rise to improved approaches to cancer treatment. However, many basic questions about the molecular mechanisms of GF receptor activation and signaling remain unanswered. We propose to develop new methods for the quantitative mechanistic study of GF receptor signaling, using the multicomponent RE-arranged during Transfection (RET) receptor as a test case. RET is a receptor tyrosine kinase that is the receptor for the glial cell-line deried neurotrophic factor (GDNF) family of neurotrophins. Deregulation of RET signaling is causally involved in several types of cancer, including multiple endocrine neoplasias (MEN) 2A and -2B, medullary thyroid carcinoma, parathyroid hyperplasia, and phaeochromocytoma. We propose to characterize the molecular mechanisms of RET activation and signaling by pursuing following three aims: 1) genetically encoded fluorescence resonance energy transfer (FRET) constructs will be used to develop a reporter system for monitoring RET association events on the surface of live cells using flow cytometry. 2) The FRET reporter constructs developed in Aim 1, will be used to address key questions concerning the mechanism of RET activation on live cells. These questions include addressing the difficult and longstanding uncertainty concerning whether GF receptors function by ligand-induced receptor dimerization, or alternatively by causing a structural rearrangement within pre-associated receptor dimers or oligomers. 3) The mechanisms and impact of crosstalk between RET and vascular endothelial growth factor receptor 2 (VEGFR2) will be explored, to establish at what levels in RET signaling crosstalk occurs and how the effects on RET function depend on the level of VEGFR2 stimulation. Collectively, these three aims will establish new methods to elucidate mechanisms of GF receptor activation, and will establish the mechanisms and impact of crosstalk between two different families of GF receptors. This research will help the fellow achieve her career goal, which is to lead an academic research group that addresses important biological problems relating to human health. She plans to address these problems by working at the molecular, cellular and in vivo levels of systems complexity, employing primarily a hypothesis-driven and (where appropriate) a quantitative perspective. The training plan in her graduate work will enable her to focus on developing her knowledge and capabilities of molecular and cellular approaches, with the idea that she will go on to encompass in vivo techniques and perspectives through post doctoral study in a suitable laboratory. Working together, the candidate and her sponsor have developed a highly effective plan for how to achieve the training she will need to meet her long-term career objectives.