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--朗沃斯，米歇尔·S。 一类长散布的Element-1s(L1s)的表达和逆转座 内源性逆转录素通过以下途径诱导上皮细胞产生I型干扰素(干扰素α和干扰素β 包括维甲酸诱导基因I在内的模式识别受体的激活 (RIG-I)样受体(RLRs)。干扰素刺激的基因驱动抑制L1的机制， 作为反馈循环的一部分，这也可能导致细胞死亡。因此，RTE/L1去- 抑制和随后的干扰素诱导(称为病毒MIMCREY)目前正在作为一种 潜在的杀死癌细胞的机制，以及更好地理解潜在的 机制将有利于癌症治疗的发展。我们的实验室发现凝集素I 和凝聚素II复合体抑制内源性和转染性L1的表达和 原代和转化的上皮细胞中的逆转录转座。凝聚素是必不可少的，多种- 亚基复合体，以其在组织基因组中的典型功能而闻名。我们的 初步数据显示凝聚素I和凝聚素II蛋白是L1介导的必需蛋白 在肿瘤来源和原代上皮细胞中诱导I型IFN，并可能起到协同作用 在细胞质中相互作用以诱导干扰素。重要的是，凝集素不足的细胞不能 诱导I型干扰素转录，即使内源性L1表达增加，放置 凝聚素蛋白在L1下游的这一途径，并提示了一个新的作用 凝集素在RTE介导的先天免疫信号中的作用。这项提案的总体目标 是确定L1的表达如何影响凝聚素促进I型干扰素的转录 并发现凝聚素在L1介导的先天免疫信号反应中的新角色。我们的 中心假说是凝聚素I和凝集素II复合体协同促进RLR 途径驱动的I型干扰素诱导对L1RNA水平增加的反应。我们将对此进行测试 通过以下目标进行假说：目的1.确定L1 RNA水平是否增加 影响凝聚素蛋白的定位、结合和活性，以及目的2。确定 凝聚素蛋白促进L1诱导I型干扰素应答的机制 表情。拟议工作的预期结果包括确定新的角色 关于凝聚素在先天性免疫信号中的作用，鉴定细胞质的潜在作用 凝聚素蛋白，以及对L1表达如何促进I型干扰素的更好理解 在肿瘤来源的细胞和原代细胞中均有诱导。这些发现将为以下工作奠定基础 调节rTE介导的干扰素诱导杀伤作用的新疗法的未来发展 癌细胞。