Interplay between LINE-1 retrotransposons, condensins, and IFN

LINE-1 逆转录转座子、凝缩蛋白和 IFN 之间的相互作用

• 批准号: 10655795
• 负责人: Michelle S Longworth
• 金额: $ 42.48万
• 依托单位: CLEVELAND CLINIC LERNER COM-CWRU
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-06-01 至 2027-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10655795
• 关键词: 3' Untranslated Regions; Binding; Biological Assay; CRISPR/Cas technology; Cell Death; Cell Line; Cells; Complex; Cytoplasm; DNA Damage; Data; Development; Elements; Engineering; Epithelial Cells; Feedback; Foundations; Future; Genes; Genetic Transcription; Genome; Human Genome; Immune checkpoint inhibitor; Immune signaling; Innate Immune Response; Interferon Type II; Interferon alpha; Interferons; Knowledge; Ligation; Long Interspersed Elements; Malignant Neoplasms; Mediating; Nuclear; Nucleic Acids; Outcome; Pathway interactions; Pattern recognition receptor; Proteins; RNA; Receptor Signaling; Repression; Retroelements; Retrotransposition; Retrotransposon; Role; Signal Induction; Signal Transduction; Solid Neoplasm; Testing; Transfection; Translations; Tretinoin; Tumor-Derived; Up-Regulation; Viral; Work; cancer cell; cancer therapy; candidate selection; cell type; condensin; derepression; inhibitor; knock-down; microbial products; mutant; novel; novel therapeutics; receptor; repaired; response; therapeutic development

Project summary- Longworth, Michelle S. The expression and retrotransposition of Long Interspersed Element-1s (L1s), a type of endogenous retroelement (RTE), induces Type I IFN (IFNα and IFNβ) in epithelial cells through activation of Pattern Recognition Receptors (PRRs) including retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs). Interferon stimulated genes drive mechanisms which repress L1, as part of a feedback loop, and which can also lead to cell death. Therefore, RTE/L1 de- repression and subsequent IFN induction (termed viral mimcry) is currently being studied as a potential mechanism to kill cancer cells, and a better understanding of the underlying mechanisms will benefit cancer therapeutic development. Our lab discovered that condensin I and condensin II complexes inhibit endogenous and transfected L1 expression and retrotransposition in primary and transformed epithelial cells. Condensins are essential, multi- subunit complexes that are known for their canonical functions in organizing the genome. Our preliminary data show that condensin I and condensin II proteins are necessary for L1-mediated induction of Type I IFNs in both cancer-derived and primary epithelial cells, and may cooperate with one another in the cytoplasm to induce IFN. Importantly, condensin insufficient cells fail to induce transcription of Type I IFN, even though endogenous L1 expression is increased, placing condensin proteins downstream of L1 in this pathway and suggesting a novel role for condensins in RTE-mediated innate immune signaling. The overall objectives of this proposal are to determine how L1 expression influences condensins to promote Type I IFN transcription and uncover novel roles for condensins in L1-mediated innate immune signaling responses. Our central hypothesis is that condensin I and condensin II complexes cooperate to promote RLR pathway-driven Type I IFN induction in response to increased levels of L1 RNA. We will test this hypothesis through the following aims: AIM 1. Determine whether increased L1 RNA levels impact condensin protein localization, association, and activity, and AIM 2. Identify the mechanisms by which condensin proteins facilitate Type I IFN induction in response to L1 expression. The expected outcomes of the proposed work include the identification of new roles for condensins in innate immune signaling, identification of potential roles for cytoplasmic condensin proteins, and a better understanding of how L1 expression facilitates Type I IFN induction in both tumor-derived and primary cells. These findings will lay the foundation for future development of novel therapeutics that modulate RTE-mediated IFN induction to kill cancer cells.

项目摘要- Longworth，Michelle S. 长散布元件-1s（L1 s）是一种基因型， 内源性逆转录因子（RTE）通过以下途径在上皮细胞中诱导I型IFN（IFNα和IFNβ）： 包括视黄酸诱导基因I的模式识别受体（PRR）的激活 （RIG-I）样受体（RLR）。干扰素刺激基因驱动抑制L1的机制， 作为反馈回路的一部分，这也会导致细胞死亡。因此，RTE/L1 de- 抑制和随后的干扰素诱导（称为病毒mimcry）目前正在研究作为一种 杀死癌细胞的潜在机制，以及更好地了解 机制将有利于癌症治疗的发展。我们的实验室发现凝聚素I 和缩合蛋白II复合物抑制内源性和转染的L1表达， 原代和转化上皮细胞中的逆转录转座。冷凝是必不可少的，多- 亚基复合物，已知其在组织基因组中的典型功能。我们 初步数据表明，凝聚素I和凝聚素II蛋白是L1介导的 在癌源性和原代上皮细胞中诱导I型IFN，并且可以协同 在细胞质中相互作用以诱导IFN。重要的是，凝结不足的细胞不能 诱导I型IFN转录，即使内源性L1表达增加， 在这一途径中，L1下游的缩合蛋白，并提出了一种新的作用， 凝集素在RTE介导的先天免疫信号传导中的作用。本提案的总体目标 是为了确定L1表达如何影响凝聚素，以促进I型IFN转录 并揭示了凝聚素在L1介导的先天免疫信号应答中的新作用。我们 中心假设是缩合蛋白I和缩合蛋白II复合物协同促进RLR 响应于L1 RNA水平增加的途径驱动的I型IFN诱导。我们将测试这个 假设通过以下目的：目的1.确定L1 RNA水平是否增加 影响凝聚素蛋白定位、结合和活性，以及AIM 2。识别 凝集素蛋白促进I型IFN诱导的机制 表情拟议工作的预期成果包括确定新的作用 对于先天免疫信号传导中的凝聚素，细胞质的潜在作用的鉴定 凝聚素蛋白，以及更好地理解L1表达如何促进I型IFN 在肿瘤衍生细胞和原代细胞中的诱导。这些发现将为 调节RTE介导的IFN诱导杀伤的新疗法的未来发展 癌细胞