Structure And Mechanism In Intracellular Notch Signaling

Notch信号是一种跨膜信号转导 细胞命运决定，发育， 稳态和神经系统功能。遗传性病变 途径与人类疾病状态如癌症和神经系统疾病有关。 紊乱这一途径的一个中心组成部分是胞质~ 1000残基 Notch跨膜受体;在激活该途径后， 受体片段由蛋白酶释放，并增强下游 信号事件。这种称为NIC的可溶性片段的活性是 由至少9种细胞内效应蛋白调节， 被认为是直接的互动。因此，NIC是一个复杂网络的枢纽， 交互. 本文提出的研究目的是阐明和量化 这个网络如何调节的分子机制和结构细节 信号传导并决定细胞命运。巴里克医生将鉴定并描述 结构和功能领域沿着NIC通过分析解决方案 衍生自以下的嵌套和重叠多肽的结构和稳定性 妮珂还将确定细胞内的结构域图。 效应器然后，这些域将用于分析成对和更高阶 交互.一个系统的高通量的方法将筛选定性 对于所有可能的成对相互作用;常规溶液热力学 方法将被用来量化成对相互作用的强度。博士 巴里克将研究现有Notch途径突变对结构的影响， 稳定性和成对相互作用，以帮助将体外结果与 信号通路的生物学。多蛋白质间的变构相互作用 我们的NIC和效应域将被识别和量化;阐明 这种相互作用将有助于阐明调节 陷波信号。最后，巴里克博士将结晶结构域， 复合物，以提供域和复合物的原子级描述， X射线晶体学

DESCRIPTION: Notch signaling is a general transmembrane signal transduction pathway that is essential for cell fate determination, development, homeostasis, and nervous system function in eukaryotes. Genetic lesions in the pathway are linked to human disease states such as cancer and neurological disorders. A central component of this pathway is the cytosolic -1000 residues of the Notch transmembrane receptor; upon activation of the pathway, this receptor fragment is released by a protease, and potentiates downstream signaling events. The activity of this soluble fragment, termed NIC, is modulated by at least nine intracellular effector proteins through what is thought to be direct interactions. Thus, NIC is the hub of a complex network of interactions. The aim of the research proposed here is to elucidate and quantify the molecular mechanisms and structural details of how this network modulates signaling and determines cell fate. Dr. Barrick will identify and characterize the structural and functional domains along NIC through analysis of solution structure and stability of nested and overlapping polypeptides derived from NIC. Structural domain maps will also be determined for intracellular effectors. These domains will then be used to analyze pairwise and higher order interactions. A systematic high-throughput approach will screen qualitatively for all possible pairwise interactions; conventional solution thermodynamic methods will be used to quantify the strength of pairwise interactions. Dr. Barrick will study the effect of existing Notch pathway mutations on structural stability and pairwise interactions, to help connect in vitro results to the biology of the signaling pathway. Multi-protein allosteric interactions among our NIC and effector domains will be identified and quantified; elucidation of such interactions will help to clarify the molecular mechanisms that modulate Notch signaling. Finally, Dr. Barrick will crystallize structural domains and complexes to provide an atomic level description of domains and complexes by x-ray crystallography.