C/EBPβ Regulation of the Type 1 IFN Response; Sensitizing Keratinocytes to Direct Activators of Cytosolic PRRs and DNA Damage-Induced Cell Death

C/EBPβ 1 型干扰素反应的调节；

• 批准号: 10735531
• 负责人: Jonathan Russell Hall
• 金额: $ 32.04万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-15 至 2028-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10735531
• 关键词: Antiviral Response; Apoptosis; Apoptotic; Autoimmune Diseases; B-DNA; Biological; CASP3 gene; CASP8 gene; CCAAT-Enhancer-Binding Protein-beta; Cell Death; Cell Death Induction; Cellular Stress; Cessation of life; Communicable Diseases; Cutaneous; DNA; DNA Damage; Data; Disease; Double-Stranded RNA; Epidermis; Genes; Genetically Engineered Mouse; Immune; Induction of Apoptosis; Infection prevention; Infectious Skin Diseases; Inflammatory; Innate Immune Response; Interferon Type I; Interferon-beta; Interferons; Laboratories; Link; Malignant Neoplasms; Mediating; Microbe; Modification; Molecular; Mus; Nerve Degeneration; Nucleic Acids; Outcome; Pathway interactions; Pattern recognition receptor; Play; Poly I-C; Proliferating; RNA; Receptor Signaling; Regulation; Repression; Research; Role; Skin; Skin Cancer; Up-Regulation; Viral; Virus; Virus Diseases; antimicrobial; experimental study; in vivo; keratinocyte; new therapeutic target; novel; pathogen; receptor; response; senescence; transcription factor; type I interferon receptor

Cellular stress, DNA damage, pathogen insult, and immune mechanisms can activate molecular pathways that result in regulated cell death. Increasing our understanding of the pathways that regulate cell death decisions in response to cellular stress is critical as misregulated cell death is linked to cancer, neurodegeneration and autoimmune diseases. The epidermis is the first line of defense to cutaneous microbes, viruses and environmental insults, and keratinocytes play a critical role in the host innate immune response mediated by type I interferons (IFN-I). In addition to anti-microbial and anti-viral responses this same IFN-I response also mediates diverse cellular and biological responses such as proliferation, apoptosis, senescence and the DNA damage response. Recent data from out laboratory suggest that the CCAAT/enhancer-binding protein-β (C/EBPβ) transcription factor is a novel regulator the keratinocyte type IFN-I response. We observed the conditional deletion of C/EBPβ in mouse epidermis (CKOβ) resulted in increased expression of IFNb and numerous ISGs which included cytosolic pattern recognition receptors (cPRRs). cPRRs sense viral/pathogen RNA and DNA as well as damaged host cytosolic DNA and RNA to trigger a IFN-I response. CKOβ keratinocytes treated with direct activators of cytosolic PRRs displayed a greatly increased IFN-I response that surprisingly resulted in increased apoptosis via the activation of caspase-8 and caspase-3. As breifly mentioned, DNA damage can activate the innate immune response. DNA damaging agents can result in modifications and structural changes in RNA and DNA that could potentially be sensed by cytosolic PRRs. We observed that CKOβ keratinocytes challenged with DNA damage displayed increase caspase 8-mediated apoptosis that was dependent on the interferon a/b receptor (INFAR). Activation of a type IFN-I response can result in the increased expression of ISGs with apoptotic functions that activate caspase-8 mediated apoptosis via death receptor signaling. The objective of this proposal is to understand molecular basis for how C/EBPβ negatively regulates the IFN-I response and caspase-8 mediated apoptosis in response to direct activators of cytosolic PRRs and DNA damage in vivo in mouse epidermis and in primary keratinocytes. We hypothesize that C/EBPβ negatively regulates the IFN-I response in keratinocytes and the loss of C/EBPβ sensitizes keratinocytes to the direct activation of cytosolic PRRs by pathogen RNA/DNA or damaged host RNA/DNA to induce pro-apoptotic ISGs and caspase 8-mediated apoptosis. These experiments will increase our understanding of a novel pathway by which C/EBPβ regulates activation of cPRRs and the IFN-I response to control cell death decisions in response to cellular stress including DNA damage. This increased understanding could identify new therapeutic targets to restore proper regulation of cell death to treat skin cancer, skin infectious diseases, and skin autoimmune diseases.

细胞应激，DNA损伤，病原体损伤和免疫力学可以激活分子途径 导致调节细胞死亡。增加我们对调节细胞死亡决定的途径的理解 响应细胞应激至关重要，因为未调节的细胞死亡与癌症，神经退行性和 自身免疫性疾病。表皮是皮肤微生物，病毒和 环境侮辱和角质形成细胞在宿主先天免疫响应中起着至关重要的作用 类型I干扰素（IFN-I）。除了抗微生物和抗病毒反应外，同样的IFN-I反应也 介导多种细胞和生物学反应，例如增殖，凋亡，感应和DNA 伤害响应。来自OUT实验室的最新数据表明CCAAT/增强子结合蛋白-β （C/EBPβ）转录因子是一种新型调节剂角质形成型IFN-I反应。我们观察到 小鼠表皮（CKOβ）中C/EBPβ的条件缺失导致IFNB和 包括胞质模式识别受体（CPRR）的许多ISG。 CPRR感知病毒/病原体 RNA和DNA以及受损的宿主胞质DNA和RNA触发IFN-I反应。 CKOβ 用胞质PRR的直接激活剂处理的角质形成细胞显示出大大增加的IFN-I反应 出乎意料的是，通过激活caspase-8和caspase-3导致凋亡增加。像Breifly 提到的，DNA损伤可以激活先天的免疫响应。 DNA损伤剂可能导致 RNA和DNA的修饰和结构变化可能会被胞质PRR感测。我们 观察到表现出的DNA损伤挑战的CKOβ角质形成细胞增加了caspase 8介导的 取决于干扰素A/B受体（基础）的凋亡。 IFN-I响应类型的激活可以 导致ISG的表达增加，凋亡功能激活caspase-8介导的凋亡 通过死亡受体信号传导。该建议的目的是了解C/EBPβ的分子基础 负调节IFN-I反应和caspase-8介导的细胞凋亡，以响应于直接激活因子 小鼠表皮和原发性角质形成细胞中体内的胞质PRR和DNA损伤。我们假设 C/EBPβ负调节角质形成细胞中的IFN-I反应和C/EBPβ敏感性的丧失 角质形成细胞通过病原体RNA/DNA或受损的宿主RNA/DNA直接激活胞质PRR 诱导凋亡的ISG和caspase 8介导的凋亡。这些实验将增加我们的 了解C/EBPβ调节CPRR的激活和IFN-I响应的新途径的理解 控制细胞死亡对细胞应激的决定，包括DNA损伤。这增加了 理解可以识别新的治疗靶标，以恢复对细胞死亡的适当调节以治疗皮肤 癌症，皮肤传染病和皮肤自身免疫性疾病。