Regulation of the Cell Death Program by DFNA5

DFNA5 对细胞死亡程序的调节

基本信息

批准号：
10531607
负责人：
Emad S Alnemri
金额：
$ 53.75万
依托单位：
THOMAS JEFFERSON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-01-01 至 2024-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10531607
关键词：
Amplifiers Animal Model Apoptosis Apoptotic Autoimmune Autoimmune Diseases Autoimmunity Biochemical Biological CASP1 gene CASP3 gene Caspase Cell Death Cell Membrane Permeability Cell Proliferation Cell membrane Cells Cessation of life Colorectal Cancer Cytolysis DNA Methylation Data Defect Dependence Development Disease Excision Extracellular Space Extravasation Family member Fever Fire - disasters Generations Greek Growth Homeostasis Homo Human Immune Immunologics Impairment In Vitro Induction of Apoptosis Infection Inflammasome Inflammation Inflammatory Innate Immune Response Knockout Mice Light Lymphocyte Lysosomal Storage Diseases Lytic Macrophage Malignant - descriptor Malignant Neoplasms Mammals Membrane Mitochondria Mus N-terminal Natural Immunity Nature Necrosis Osmosis Outcome Outer Mitochondrial Membrane Pathway interactions Permeability Phagocytes Phagocytosis Phase Physiological Play Post-Translational Protein Processing Process Proteins Ptosis Regulation Research Role Secondary to Septic Shock Signal Pathway Signal Transduction Stimulus Swelling Testing Tissues Tumor Suppression Tumor Suppressor Genes Vesicular stomatitis Indiana virus Virus Diseases cancer cell cell type cytochrome c deafness experimental study falls in vivo insight novel novel therapeutic intervention pathogen pathogenic microbe pathogenic virus programs public health relevance receptor response tissue culture tumor

项目摘要

Abstract Apoptosis and pyroptosis play key physiological roles in growth, survival, homeostasis and innate immunity of all mammals. Disregulation of these pathways could lead to many diseases including autoimmune, inflammatory, atherosclerotic and malignant diseases. While apoptosis is an immunologically “silent” form of programmed cell death executed by activation of the effector caspases 3, 6 and 7, pyroptosis is an inflammatory form of programmed cell death executed by activation of the inflammatory caspases 1, 4, and 5 in humans. These inflammatory caspases cleave the gasdermin protein, GSDMD, to generate a pore- forming N-terminal fragment that permeabilizes the plasma membrane leading, to cellular swelling, osmotic cell lysis and leakage of intracellular contents. If apoptotic cells are not scavenged, such as seen under in vitro culture conditions or conditions of impaired phagocytosis in vivo, they progress to a lytic and inflammatory phase called secondary necrosis. Secondary necrosis shares several features with pyroptosis including plasma membrane permeabilization, swelling, and lysis, and therefore it could represent a form of pyroptosis. Indeed, we discovered recently that activated caspase-3 cleaves the gasdermin-related protein DFNA5 during apoptosis to generate a necrotic DFNA5-N fragment that targets the plasma membrane to permeabilize it and induce secondary necrosis/pyroptosis. Interestingly, unlike WT cells, DFNA5-deficient cells do not roundup and swell, but extensively fragment into small apoptotic bodies suggesting that DFNA5 is a regulator of cellular disassembly during apoptosis. As cellular disassembly during apoptosis may impact clearance of dying cells by phagocytes, we propose to test the hypothesis that DFNA5 cleavage during apoptosis induces pores in the plasma membrane to release “find me” and other phagocyte activation signals to clear apoptotic cells and to temper down disassembly of apoptotic cells into small apoptotic bodies. In this application we propose aims to gain further insight into the physiological function of DFNA5 in vivo, and its role in autoimmunity, inflammation and innate immunity. We will study the clearance of apoptotic cells in DFNA5-deficient mice and further assess the pathophysiological consequences of DFNA5 deficiency in the development of autoimmunity. We will also characterize another novel function of DFNA5 involved in the regulation of the mitochondrial apoptotic pathway and how this activity might impact cell proliferation and sensitivity to apoptotic stimuli. Finally, we will investigate the role of DFNA5 in the host innate immunity against viral pathogens, septic shock and inflammation-induced malignancy. Results from this research should have a high impact on the field and increase our understanding of the signaling pathways activated during the apoptotic program leading to cell permeabilization and their impact on tissue homeostasis, and autoimmune and inflammatory diseases.

抽象的凋亡和凋亡在生长，生存，稳态和先天免疫中起关键的生理作用在所有哺乳动物中。疏离这些途径可能导致许多疾病，包括自身免疫性，炎症，动脉粥样硬化和恶性疾病。凋亡是一种免疫学上的“沉默”形式的通过激活效应子胱天蛋白酶3、6和7执行的程序性细胞死亡，凋亡是一种通过激活炎症胱天蛋白酶1、4和 5在人类中。这些炎症性胱天蛋白酶清除了Gasdermin蛋白GSDMD，以产生孔隙形成N末端片段，使质膜通透，导致细胞肿胀，渗透细胞裂解和细胞内含量的泄漏。如果未清除凋亡细胞，例如在体内吞噬作用受损的体外培养条件或条件，它们会发展为裂解和炎症阶段称为继发性坏死。继发性坏死具有多种特征，包括质膜透化，肿胀和裂解，因此可以代表一种凋亡的形式。确实，我们最近发现激活的caspase-3裂解了与加油机相关的蛋白DFNA5在凋亡产生坏死的DFNA5-N片段，该片段靶向质膜，以使其透化，并且诱导继发性坏死/凋亡。有趣的是，与WT细胞不同，DFNA5缺陷细胞不会综述和膨胀，但广泛地碎片成小凋亡人物，表明dfna5是细胞的调节剂凋亡期间拆卸。由于细胞凋亡期间的细胞拆卸可能会影响垂死细胞的清除通过吞噬细胞，我们建议检验以下假设：凋亡过程中DFNA5裂解会诱导孔中的毛孔释放“找到我”和其他吞噬细胞激活信号的质膜以清除凋亡细胞和将凋亡细胞拆卸成小凋亡人士。在此应用中，我们提出了目标为了进一步了解体内DFNA5的物理功能及其在自身免疫性中的作用，炎症和先天免疫。我们将研究DFNA5缺陷小鼠中凋亡细胞的清除率并进一步评估DFNA5缺乏在发展中的病理生理后果自身免疫性。我们还将表征参与调节的DFNA5的另一个新功能线粒体凋亡途径以及该活性如何影响细胞增殖和对凋亡的敏感性刺激。最后，我们将研究DFNA5在宿主先天免疫中的作用，以抗病毒病原体，败血性休克和炎症引起的恶性肿瘤。这项研究的结果应该对该领域并增加了我们对凋亡程序中激活的信号通路的理解导致细胞通透性及其对组织稳态的影响，以及自身免疫性和炎症疾病。