STRUCTURAL BIOLOGY OF NOTCH SIGNAL TRANSDUCTION

NOTCH 信号转导的结构生物学

• 批准号: 8361627
• 负责人: STEPHEN C BLACKLOW
• 金额: $ 0.37万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8361627
• 关键词: Acute T Cell Leukemia; Binding Sites; Biochemical; Cell Death; Cell Differentiation process; Cell Nucleus; Cell membrane; Cells; Complex; DNA; Development; Dimerization; Elements; Event; Foundations; Funding; Gene Expression Regulation; Genetic Transcription; Goals; Grant; Head; Ligands; Malignant Neoplasms; Mediating; Mutate; National Center for Research Resources; Organism; Patients; Principal Investigator; Proteins; Research; Research Infrastructure; Resources; Role; Signal Transduction; Site; Source; Surface; T cell differentiation; Techniques; United States National Institutes of Health; Work; cell growth; cost; dimer; human disease; leukemia; mouse model; mutant; notch protein; receptor; structural biology

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Notch proteins are conserved surface receptors that regulate development through cell-cell contact in multicellular organisms. Notch signaling triggers cell growth, cell differentiation, or cell death, in a context dependent manner. Upon activation by ligand engagement, Notch is released from the cell membrane by two proteolytic events, allowing the intracellular portion (ICN) to move to the nucleus. ICN associates with two other proteins, CSL and Mastermind, in the nucleus to form the Notch transcription complex (NTC), which activates gene transcription. Aberrant Notch signals have been implicated in cancer and a number of human diseases. More than half of T-cell acute lymphoblastic leukemia (T-ALL) patients have mutated forms of Notch that are constitutively active, resulting in aberrant transcription of Notch targets. Trimer NTCs can self-associate on specialized DNA elements with two CSL-binding sites oriented head-to-head with a defined spacer between the two sites, referred to as an SPS (for Sequence Paired Site or Supressor of Hairless Paired Site). A mutant form of ICN (R1985A) is able to assemble into NTC complexes and perform some known Notch functions, including promotion of T cell differentiation. However this mutant form of ICN is not able to form dimers and does not promote leukemia in a mouse model for T-ALL in which wild-type ICN is leukemogenic. The goal of this work is to determine the structural and energetic foundations underlying Notch mediated dimerization and explore its role in gene regulation using biophysical, biochemical and cellular techniques.

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 Notch蛋白是保守的表面受体，通过多细胞生物中的细胞与细胞接触调节发育。Notch信号传导以环境依赖性方式触发细胞生长、细胞分化或细胞死亡。在通过配体接合激活后，Notch通过两个蛋白水解事件从细胞膜释放，允许细胞内部分（ICN）移动到细胞核。ICN与细胞核中的另外两种蛋白CSL和Mastermind结合形成Notch转录复合物（NTC），其激活基因转录。异常Notch信号与癌症和许多人类疾病有关。超过一半的T细胞急性淋巴细胞白血病（T-ALL）患者具有组成型活性的Notch突变形式，导致Notch靶点的异常转录。三聚体NTC可以在具有头对头定向的两个CSL结合位点的特化DNA元件上自缔合，在两个位点之间具有限定的间隔区，称为SPS（用于序列配对位点或无毛配对位点的抑制子）。 ICN的突变形式（R1985A）能够组装成NTC复合物并执行一些已知的Notch功能，包括促进T细胞分化。然而，这种突变形式的ICN不能形成二聚体，并且在野生型ICN是致白血病的T-ALL小鼠模型中不会促进白血病。这项工作的目标是确定Notch介导的二聚化的结构和能量基础，并利用生物物理，生物化学和细胞技术探索其在基因调控中的作用。