Elucidation of Novel Post-Translational Mechanisms That Regulate Notch Activity

描述（由申请人提供）：Notch信号传导的失调与许多生物体和人类疾病的发育缺陷有关，最明显的是T细胞急性淋巴细胞白血病（T-ALL）。这项研究将表征的调节激活形式的Notch在发展背景下使用秀丽隐杆线虫。具体来说，这项研究将研究两种潜在的新形式的负调控，不理解的机制水平。这两种形式的监管块C。LIN-12/Notch在细胞核中的功能。在一种情况下，与Ras-MAP激酶途径的串扰阻断了组成型活性LIN-12/Notch的作用，特别是在Ras-MAP激酶被激活的情况下。在第二种情况下，新的DNA结合蛋白，LIN-14，它调节发育时间，阻断组成型活性LIN-12/Notch在特定组织。LIN-12阻断的组成型活性形式类似于在某些癌症如T-ALL中发现的突变。在这项研究的过程中，我将描述两个所需的Notch辅助蛋白，一个保守的转录因子（LAG-1）和一个辅激活因子（SEL-8）的调控，以及它们与LIN-12形成的转录复合物。此外，这些方法将被扩展到表征通过操纵LIN-12靶报告基因发现的其他形式的调节。通过表征这两种机制，该提案旨在增加对关键Notch通路如何调节的理解，并可能为T-ALL等疾病提供新的治疗策略。

DESCRIPTION (provided by applicant): The misregulation of Notch signaling has been implicated in developmental defects in many organisms and in human diseases, most notably T-Cell Acute Lymphoblastic Leukemia (T-ALL). This research will characterize the regulation of activated forms of Notch in developmental contexts using Caenorhabditis elegans. Specifically, this research will examine two potentially novel forms of negative regulation that are not understood at the mechanistic level. Both forms of regulation block C. elegans LIN-12/Notch function in the nucleus. In one case, crosstalk with the Ras-MAP kinase pathway blocks the effect of constitutively active LIN-12/Notch specifically where Ras-MAP kinase is activated. In the second case, the novel DNA-binding protein, LIN-14, which regulates developmental timing, blocks constitutively active LIN-12/Notch in a particular tissue. The constitutively active forms o LIN-12 blocked is analogous to mutations found in certain cancers such as T-ALL. In the course of this research, I will characterize the regulation of two required Notch accessory proteins, a well-conserved transcription factor (LAG-1) and a coactivator (SEL-8), and the transcriptional complex they form with LIN-12. Additionally, these methods will be expanded to characterize additional forms of regulation found through manipulation of LIN-12 target reporters. By characterizing these two mechanisms, this proposal aims to increase the understanding of how the critical Notch pathway is regulated and potentially provide novel therapeutic strategies for diseases such as T-ALL.