Dissecting BRCA1-PALB2 Activity in DNA Repair and Development

剖析 BRCA1-PALB2 在 DNA 修复和发育中的活性

基本信息

批准号：
10453625
负责人：
Neil Johnson
金额：
$ 40.83万
依托单位：
RESEARCH INST OF FOX CHASE CAN CTR
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-08-05 至 2024-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10453625
关键词：
Address Alleles Amino Acids BRCA1 Mutation BRCA1 Protein BRCA1 gene BRCA2 Mutation BRCA2 gene Binding Biochemical Biological Assay Breast Cells Cessation of life Characteristics Chromatin Coiled-Coil Domain Complex DNA DNA Damage DNA Double Strand Break DNA Repair DNA Repair Pathway Defect Development Disease Embryo Embryonic Development Fanconi&apos s Anemia Filament Genetic Epistasis Genome Genomic Instability Goals Health Heterodimerization Human Cell Line Immunoprecipitation Kinetics Knock-out Laboratories Link Maintenance Malignant Neoplasms Malignant neoplasm of ovary Mediating Molecular Mus Mutant Strains Mice Mutation Nature PALB2 gene Patients Peptides Phenotype Proteins Recruitment Activity Role Site Structure System Tertiary Protein Structure United States Work base developmental disease experimental study genome integrity homologous recombination insight malignant breast neoplasm mouse genetics mouse model mutant mouse model mutation carrier neonatal mice novel postnatal development prevent protein complex recruit ubiquitin ligase ubiquitin-protein ligase

项目摘要

PROJECT SUMMARY The BRCA1 and PALB2 proteins directly heterodimerize through their respective coiled-coil (CC) domains, facilitating the formation of a larger BRCA1-PALB2-BRCA2-RAD51 complex that is required for RAD51 filament formation. Currently, little is known about the structural basis of the BRCA1-PALB2 interaction, including the residue alignment and orientation of physically interacting -helices. Elucidating CC molecular interactions is critical for understanding how mutations found in patients disrupt peptide interactions and promote disease. Protein CC domains are capable of mediating interactions with several CC domain containing partners. However, BRCA1 and PALB2 form the only known interaction that is mediated by their respective CC domains. Whether BRCA1 and PALB2 CC domains exclusively interact with one another, or if there are additional CC interactions and functions is unknown. Our laboratory has developed novel BRCA1 and PALB2 CC domain mutant mouse models to investigate the significance of this interaction in DNA repair and organismal health. We have also purified CC peptides so that biochemical assays can be performed assessing the effects of mutations on complex interactions and activity. The only known function of BRCA1 and PALB2 CC domains is to interact with one another, thus, BRCA1CC and PALB2CC homozygous mice might be expected to have identical phenotypes. However, while BRCA1CC mice are born at sub-Mendelian ratios and neo-natal mice demonstrate a range of developmental defects, PALB2CC homozygosity resulted in early embryonic lethality. Because BRCA1CC and PALB2CC mice have distinct phenotypes, we hypothesize that CC domains facilitate protein interactions beyond the BRCA1-PALB2 heterodimer that promote DNA repair and embryonic development. We will address the following Specific Aims: 1) Determine biochemical CC interactions and activity; 2) Uncover DNA repair and developmental defects in CC mutant mice; and 3) Elucidate mechanisms of BRCA1-PALB2 complex recruitment to DNA breaks. Collectively, the proposed experiments will yield new insight into the mechanism by which the BRCA1-PALB2 complex protects from genome instability.

项目概要 BRCA1 和 PALB2 蛋白通过各自的卷曲螺旋 (CC) 结构域直接异二聚化，促进 RAD51 丝所需的更大 BRCA1-PALB2-BRCA2-RAD51 复合物的形成目前，人们对 BRCA1-PALB2 相互作用的结构基础知之甚少，包括物理相互作用的 α-螺旋的残基排列和方向阐明了 CC 分子相互作用。对于理解患者中发现的突变如何破坏肽相互作用并促进疾病至关重要。蛋白质 CC 结构域能够介导与多个含有 CC 结构域的伙伴的相互作用。 BRCA1 和 PALB2 形成唯一已知的由各自 CC 结构域介导的相互作用。 BRCA1 和 PALB2 CC 结构域仅彼此相互作用，或者是否存在其他 CC 相互作用本实验室已开发出新型BRCA1和PALB2 CC结构域突变小鼠。我们还建立了模型来研究这种相互作用在 DNA 修复和生物健康中的重要性。纯化 CC 肽，以便可以进行生化测定，评估突变对复合物的影响 BRCA1 和 PALB2 CC 结构域的唯一已知功能是与其中一个相互作用。因此，BRCA1CC 和 PALB2CC 纯合小鼠可能具有相同的表型。然而，虽然 BRCA1CC 小鼠出生时的比例低于孟德尔，而且新生小鼠表现出一系列发育缺陷，PALB2CC纯合性导致早期胚胎死亡，因为BRCA1CC和。 PALB2CC 小鼠具有不同的表型，我们认为 CC 结构域促进蛋白质相互作用我们将解决促进 DNA 修复和胚胎发育的 BRCA1-PALB2 异二聚体。具体目标如下： 1) 确定生化 CC 相互作用和活性 2) 揭示 DNA 修复和活性； CC 突变小鼠的发育缺陷；3) 阐明 BRCA1-PALB2 复合物募集机制总的来说，所提出的实验将对 DNA 断裂的机制产生新的见解。 BRCA1-PALB2 复合物可防止基因组不稳定。