Characterization of the p53-CBP/p300 Transcriptional Activator-Coactivator Complex

p53-CBP/p300 转录激活剂-辅激活剂复合物的表征

• 批准号: 10077857
• 负责人: Melody Sanders
• 金额: $ 0.83万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-01-01 至 2021-02-01
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10077857
• 关键词: Acetyltransferase; Affinity; Apoptosis; Architecture; Avidity; Behavior; Binding; Biochemical; Biological Assay; Biological Process; Biophysics; CREBBP gene; Calorimetry; Cell Proliferation; Chromatin; Complex; Cryoelectron Microscopy; DNA Damage; DNA Repair; Disease; E1A-associated p300 protein; EP300 gene; Electron Microscopy; Event; Gene Expression; Genes; Genetic Transcription; Goals; Histones; Investigation; Length; Ligands; Link; Measures; Mediating; Methods; Modeling; Molecular; Molecular Conformation; Mutagenesis; Oncogenic; Play; Proteins; Reaction; Regulation; Resolution; Roentgen Rays; Role; Signal Pathway; Stress; Structural Models; Structure; TP53 gene; Thermodynamics; Titrations; Transcription Coactivator; Transcriptional Activation; Transcriptional Activation Domain; Transferase; Tumor Suppressor Proteins; Variant; Work; biophysical analysis; biophysical techniques; experimental study; histone acetyltransferase; holistic approach; insight; paralogous gene; particle; protein protein interaction; reconstitution; recruit; response; transcription factor

PROJECT SUMMARY The CREB-binding protein (CBP) and its paralog p300 are master transcriptional coactivators that integrate numerous signaling pathways and play critical roles in cell proliferation, differentiation, apoptosis, and DNA repair. The biological functions of CBP and p300 are largely exerted through multiple transcription factor interaction domains as well as a histone acetyl transferase (HAT) domain. However, a structural model of how transcription factor complexes with CBP and p300 modulate coactivator function is lacking. A well-studied cellular partner of CBP and p300 is the tumor suppressor protein p53. Several studies suggest that upon DNA damage CBP/p300 is recruited by p53 to modify chromatin and aid in transcriptional activation of p53 target genes. It has been hypothesized that each of the four transcriptional activation domains of an active p53 tetramer bind to four separate domains of a single CBP/p300 molecule, resulting in increased avidity that further stabilizes the p53-CBP/p300 complex and enhances p53-mediated transcription. However, the influence of p53 binding on local and global conformational changes in CBP/p300 and its effect on histone acetyltransferase activity has yet to be defined. Using a combination of single particle electron microscopy, solution biophysical and biochemical methods, the goal of the proposed work is to develop a comprehensive structure-function model of CBP/p300 in p53-mediated transcriptional activation.

项目概要 CREB ​​结合蛋白 (CBP) 及其旁系同源物 p300 是主转录共激活因子 整合众多信号通路，在细胞增殖、分化、 细胞凋亡、DNA 修复。 CBP和p300的生物学功能很大程度上是通过 多个转录因子相互作用结构域以及组蛋白乙酰转移酶 (HAT) 领域。然而，转录因子如何与 CBP 和 p300 复合的结构模型 缺乏调节共激活子功能。 CBP 和 p300 的一个经过充分研究的细胞伙伴是 肿瘤抑制蛋白p53。多项研究表明，在 DNA 损伤时，CBP/p300 由 p53 招募来修饰染色质并帮助 p53 靶基因的转录激活。它 据推测，活性 p53 的四个转录激活域中的每一个 四聚体与单个 CBP/p300 分子的四个独立结构域结合，导致 亲合力进一步稳定 p53-CBP/p300 复合物并增强 p53 介导的 转录。然而，p53 结合对局部和整体构象变化的影响 CBP/p300 及其对组蛋白乙酰转移酶活性的影响尚未确定。使用 结合单粒子电子显微镜、溶液生物物理和生化方法， 拟议工作的目标是开发一个全面的结构功能模型 p53 介导的转录激活中的 CBP/p300。