Immune control and genomic instability at micronuclei

微核的免疫控制和基因组不稳定性

基本信息

批准号：
10365554
负责人：
JOHN MACIEJOWSKI
金额：
$ 50.29万
依托单位：
SLOAN-KETTERING INST CAN RESEARCH
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-01-01 至 2026-12-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10365554
关键词：
Address Anaphase Automobile Driving Biochemical Cell Nucleus Cell division Cells Cellular biology Chromatin Chromosomal Instability Chromosome Segregation Chromosomes Chronic Collaborations Complex Crows Cytoplasm DNA DNA Binding DNA Damage DNA Sequence Rearrangement DNA-Binding Proteins Data Defect Digestion Disease Docking Electron Transport Complex III Endoplasmic Reticulum Environment Etiology Evolution Exhibits Functional disorder Genes Genome Genomic DNA Genomic Instability Goals Health Human Immune Immune System Diseases Immune signaling Incentives Individual Laboratories Lead Letters Malignant Neoplasms Membrane Methods Missense Mutation Mitosis Modeling Molecular Mutagenesis Mutate Mutation N-terminal Nuclear Nuclear Envelope Pathway interactions Pattern Phase Play Positioning Attribute Process Prognosis Proteins Proteomics Recruitment Activity Role Rupture Site Source Stimulator of Interferon Genes Structural Chromosomal Abnormality Structure TREX1 gene TREX2 gene Testing Therapeutic Three Prime Repair Exonuclease 1 Topoisomerase Tumor Immunity Vesicle Viral Work base cancer genome chromosome missegregation chromothripsis endonuclease genome integrity immune activation immunoregulation improved insight mutation carrier novel polyproline prevent protein protein interaction pseudotoxoplasmosis syndrome recruit repaired response segregation sensor tumor

项目摘要

PROJECT SUMMARY Chromosomal instability (CIN) is a hallmark of cancer characterized by high rates of chromosome mis-segre- gation during cell division. CIN can generate nuclear aberrations termed micronuclei when a chromosome or chromosome fragment lags during anaphase and fails to join the main chromatin mass that will form the prima- ry nucleus. Micronuclei recruit nuclear envelopes but defects in construction lead to frequent rupturing, loss of compartmentalization, and an unregulated exchange of proteins and small vesicles with the cytoplasm. Mi- cronuclear envelope rupturing causes broad dysfunction and is associated with extensive DNA damage and genomic rearrangements, including clustered mutational phenomena such as chromothripsis and kataegis, which are commonly observed in cancer genomes. Ruptured micronuclei can also activate the pro-inflammato- ry cGAS-STING pathway, which plays essential roles in anti-tumor immunity. These observations suggest that micronuclei may represent key platforms for genome evolution and immune activation in cancer. The mecha- nisms driving DNA damage and immune activation at micronuclei are poorly understood. The laboratory dis- covered that the endoplasmic reticulum (ER)-associated exonuclease TREX1, which is mutated in a variety of human immune diseases including Aicardi-Goutières Syndrome, accumulates at micronuclei upon micronu- clear envelope rupture where it resects micronuclear DNA and limits cGAS-STING activation. Therefore, TREX1 occupies central positions in key pathways with diverse roles in human health and disease. Conse- quently, there is strong rationale to understand mechanisms of TREX1 activity and engagement with cytosolic DNA. The long-term goals of the laboratory are to determine mechanisms of DNA damage, clustered mutage- nesis, and immune activation at sites of nuclear envelope rupture. The specific Aims of this proposal are to 1) Elucidate mechanisms of TREX1 structure and function, 2) Determine how TREX1 is recruited to micronuclei, and 3) Dissect pathways of micronuclear DNA damage. Each objective is supported by extensive preliminary data. Aim 1 will focus on a previously uncharacterized region in TREX1, which is essential for its ability to de- grade cytosolic DNA and inhibit cGAS activation. Aim 2 will build on results showing that TREX1 DNA binding function is dispensable for its localization to micronuclei, while its association with the ER is essential. Aim 3 will use a new method to purify micronuclei to dissect sources of micronuclear DNA damage. Taken together, these data will provide fundamental insights into cancer genome evolution, explain how previously uncharac- terized TREX1 mutations cause Aicardi-Goutières syndrome, and may identify new strategies to improve anti- tumor immunity.

项目概要染色体不稳定性（CIN）是癌症的一个标志，其特征是染色体错误分离率高。当染色体或细胞分裂时，CIN 会产生称为微核的核畸变。染色体片段在后期滞后并且无法加入将形成初级的主要染色质质量微核招募核膜，但结构缺陷导致频繁破裂、丢失。区室化，以及蛋白质和小囊泡与细胞质的不受控制的交换。核膜破裂会导致广泛的功能障碍，并与广泛的 DNA 损伤和基因组重排，包括簇状突变现象，例如染色体碎裂和卡塔吉斯，在癌症基因组中常见的破裂微核也可以激活促炎细胞。 ry cGAS-STING 通路在抗肿瘤免疫中发挥重要作用。微核可能代表癌症中基因组进化和免疫激活的关键平台。实验室发现，驱动 DNA 损伤和免疫激活的机制知之甚少。报道称，内质网 (ER) 相关的核酸外切酶 TREX1 在多种细胞中发生突变人类免疫疾病，包括 Aicardi-Goutières 综合征，在微核上积累透明包膜破裂，切除微核 DNA 并限制 cGAS-STING 激活因此， TREX1 在人类健康和疾病中发挥多种作用的关键通路中占据核心地位。因此，有充分的理由来理解 TREX1 活性及其与胞质结合的机制。 DNA。实验室的长期目标是确定 DNA 损伤、聚集突变的机制。 nesis 和核膜破裂部位的免疫激活该提案的具体目标是 1) 阐明 TREX1 结构和功能的机制，2) 确定 TREX1 如何被招募到微核， 3) 剖析微核 DNA 损伤的途径每个目标都有广泛的初步支持。目标 1 将重点关注 TREX1 中以前未表征的区域，这对于其去特征化的能力至关重要。级胞质 DNA 并抑制 cGAS 激活目标 2 将基于 TREX1 DNA 结合的结果。其定位于微核的功能是可有可无的，而其与 ER 的关联则是必不可少的。将使用一种新的方法来纯化微核来剖析微核 DNA 损伤的来源。这些数据将为癌症基因组进化提供基本见解，解释以前不寻常的现象是如何发生的。特化的 TREX1 突变会导致 Aicardi-Goutières 综合征，并且可能会确定新的策略来改善抗- 肿瘤免疫。