Non-apoptotic functions of caspase-2 in cell division and genomic stability

Caspase-2 在细胞分裂和基因组稳定性中的非凋亡功能

基本信息

批准号：
10394864
负责人：
Lisa Bouchier-Hayes
金额：
$ 32.53万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2018
资助国家：
美国
起止时间：
2018-05-01 至 2023-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10394864
关键词：
Aging Aneuploidy Apoptosis Apoptotic CASP2 gene Caspase Cell Cycle Cell Cycle Checkpoint Cell Cycle Progression Cell Cycle Regulation Cell Death Cell Line Cell Nucleolus Cell Proliferation Cell Survival Cell division Cell physiology Cells Chromosome abnormality Co-Immunoprecipitations Complement Complex Cytoplasm Cytosol DNA DNA Damage DNA Repair DNA replication fork Data Defect Disease Engineering Ensure Exposure to Fluorescence Foundations Fractionation Frequencies GOLGA3 gene Genes Genome Genome Stability Genomic Instability Human Image Impairment Kinetics Knowledge Laboratories Lesion Life Lymphoma MDM2 gene Malignant Neoplasms Malignant neoplasm of liver Malignant neoplasm of lung Measurable Measures Mission Molecular Mutate NPM1 gene National Institute of General Medical Sciences Nucleolar Proteins Pathway interactions Peptide Hydrolases Phenotype Phosphoproteins Physiological Play Prevention Process Prognosis Proliferating Proteins Public Health Publishing Regulation Research Role Site Stimulus TP53 gene Techniques Testing Tumor Suppression Tumor Suppressor Proteins Visualization base cell type design disease diagnosis experimental study functional outcomes homologous recombination imaging modality innovation insight irradiation malignant breast neoplasm mouse model novel nucleophosmin prevent recruit repaired replication stress response tumorigenesis

项目摘要

PROJECT SUMMARY/ABSTRACT Several groups have shown a strong association between caspase-2 deficiency and accelerated tumorigenesis in murine models of lymphoma, breast, and lung cancer. Such phenotypes are often accompanied by enhanced cell proliferation and increased genomic instability with minimal measurable apoptotic defects. Therefore caspase-2 appears to play a crucial role in maintaining genomic stability and may do so independent of its role in apoptosis. To test this, this proposal will study the mechanisms of caspase-2 is activation during the DNA damage response with a focus on the upstream caspase-2 regulator PIDD. The central hypothesis is that DNA damage induces two distinct caspase-2 activation platforms – a cytoplasmic platform that is PIDD independent and a nucleolar platform that requires PIDD – each providing access to distinct substrates that regulate genomic instability by both pro-apoptotic and non-apoptotic mechanisms. This hypothesis has been formulated based on published and preliminary data produced in the applicant’s laboratory showing that caspase-2 is activated in the cytoplasm and in the nucleolus and that the nucleolar activation is dependent on the nucleolar phosphoprotein nucleophosmin (NPM1) for both assembly and function. This hypothesis will be tested by pursuing two specific aims: 1) Determine the mechanisms of caspase-2 activation in the nucleolus versus the cytosol; and 2) Identify the relative contributions of the nucleolar and cytoplasmic complexes to downstream caspase-2 functions and how these protect from genomic instability. Under the first aim, an already proven imaging-based method for measuring caspase-2 activation, will be used to investigate the distinct mechanisms of differential caspase-2 activation in the nucleolus and in the cytosol. These experiments will specifically probe the roles of PIDD and NPM1. Under the second aim, based on preliminary data that shows that caspase-2-deficient cells, proliferate faster and accumulate more DNA damage following replication stress, the requirement of the nucleolar and cytoplasmic complexes for apoptotic and non-apoptotic caspase-2 functions will be explored in the context of apoptosis, cell cycle regulation, substrate cleavage and DNA repair mechanisms. The approach is innovative because it utilizes novel imaging-based techniques that are designed to assess caspase-2 activation in single cells so that the relationship between the localization of caspase-2 activation with apoptosis, DNA damage, and cell division will be directly explored on a per cell basis. It also provides a new paradigm of caspase activation in the nucleolus. The proposed research is significant because it is proposed that site-specific activation of caspase-2 in the cytosol and nucleolus governs distinct functions of this protease that cooperate to protect from genomic instability. These mechanisms may underlie the known physiological roles of caspase-2 in tumor suppression and in protecting against accelerated aging. Ultimately, such knowledge has the potential to inform how diseases where caspase pathways are disrupted can be treated or prevented.

项目概要/摘要多个研究小组已表明 caspase-2 缺乏与加速肿瘤发生之间存在密切关联在淋巴瘤、乳腺癌和肺癌的小鼠模型中，这种表型通常伴随着增强。细胞增殖和基因组不稳定性增加，可测量的细胞凋亡缺陷最小化。 caspase-2 似乎在维持基因组稳定性方面发挥着至关重要的作用，并且可能与其作用无关为了测试这一点，本提案将研究 DNA 过程中 caspase-2 的激活机制。损伤反应集中于上游 caspase-2 调节因子 PIDD 的中心假设是 DNA。损伤诱导两个不同的 caspase-2 激活平台——一个独立于 PIDD 的细胞质平台以及需要 PIDD 的核仁平台——每个平台都提供对调节基因组的不同底物的访问该假设是基于促凋亡和非凋亡机制而提出的。申请人实验室已发表的数据和初步数据表明 caspase-2 在细胞质和核仁中，核仁激活依赖于核仁磷蛋白核磷蛋白 (NPM1) 的组装和功能将通过追求两个特定的条件来检验。目标：1) 确定核仁与细胞质中 caspase-2 的激活机制；2) 识别核仁和细胞质复合物对下游 caspase-2 功能的相对贡献和这些如何防止基因组不稳定。第一个目标是一种已经经过验证的基于成像的方法。测量 caspase-2 激活，将用于研究差异 caspase-2 的不同机制这些实验将专门探讨 PIDD 和细胞质中的激活。 NPM1。根据初步数据显示，caspase-2 缺陷的细胞会增殖。复制压力、核仁和细胞的需要后，DNA损伤会更快地积累将在以下背景下探索凋亡和非凋亡 caspase-2 功能的细胞质复合物该方法在细胞凋亡、细胞周期调节、底物裂解和 DNA 修复机制方面具有创新性。因为它利用了新颖的基于成像的技术，旨在评估单次 caspase-2 激活细胞中 caspase-2 激活的定位与细胞凋亡、DNA 损伤和细胞分裂将直接在每个细胞的基础上进行探索，它还提供了 caspase 激活的新范例。所提出的研究意义重大，因为它提出了位点特异性激活。细胞质和核仁中的 caspase-2 控制着该蛋白酶的不同功能，这些功能协同作用以防止这些机制可能是 caspase-2 在肿瘤中已知的生理作用的基础。最终，这些知识有可能提供信息。如何治疗或预防半胱天冬酶途径被破坏的疾病。