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（L1s）的表达和逆转录转座 内源性逆转录因子 (RTE)，通过以下方式在上皮细胞中诱导 I 型干扰素（IFNα 和 IFNβ） 激活模式识别受体 (PRR)，包括视黄酸诱导基因 I (RIG-I) 样受体 (RLR) 刺激基因驱动机制，抑制 L1， 作为反馈循环的一部分，这也可能导致细胞死亡。 目前正在研究抑制和随后的干扰素诱导（称为病毒拟声） 杀死癌细胞的潜在机制，以及更好地了解潜在的机制 我们的实验室发现 condensin I 的机制将有利于癌症治疗的发展。 和凝缩蛋白 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是必需的、多方面的。 以其在组织基因组中的典型功能而闻名的亚基复合体。 初步数据表明，凝缩蛋白 I 和凝缩蛋白 II 蛋白是 L1 介导的必需蛋白 在癌源性上皮细胞和原代上皮细胞中诱导 I 型干扰素，并且可能协同作用 重要的是，凝集素不足的细胞无法诱导 IFN。 诱导 I 型 IFN 的转录，即使内源性 L1 表达增加， 该途径中 L1 下游的凝缩蛋白蛋白，表明其具有新的作用 RTE 介导的先天免疫信号传导中的凝缩蛋白 该提案的总体目标。 目的是确定 L1 表达如何影响凝缩蛋白以促进 I 型 IFN 转录 并揭示凝缩蛋白在 L1 介导的先天免疫信号反应中的新作用。 中心假设是凝缩蛋白 I 和凝缩蛋白 II 复合物协同促进 RLR 针对 L1 RNA 水平增加的途径驱动的 I 型 IFN 诱导我们将对此进行测试。 通过以下目标进行假设： AIM 1. 确定 L1 RNA 水平是否增加 影响凝缩蛋白定位、关联和活性，以及​​ AIM 2. 识别 凝缩蛋白促进 I 型 IFN 响应 L1 诱导的机制 拟议工作的预期成果包括确定新的角色。 对于先天免疫信号传导中的凝缩蛋白，鉴定细胞质的潜在作用 凝缩蛋白，以及更好地了解 L1 表达如何促进 I 型 IFN 这些发现将为肿瘤来源细胞和原代细胞的诱导奠定基础。 未来开发调节 RTE 介导的 IFN 诱导杀死细胞的新型疗法 癌细胞。