The function of Topoisomerase I SUMOylation in transcription and chemoresistance

拓扑异构酶 I SUMO 化在转录和化疗耐药中的作用

• 批准号: 9901592
• 负责人: Yilun Liu
• 金额: $ 34.6万
• 依托单位: BECKMAN RESEARCH INSTITUTE/CITY OF HOPE
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-05-01 至 2022-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9901592
• 关键词: Acute; Angelman Syndrome; Biochemical; Cell Culture Techniques; Cell Death; Cell Line; Cell physiology; Cells; Chemotherapy-Oncologic Procedure; Chromatin; Coupling; DNA; DNA Damage; DNA Repair; Disease; Enzymes; Event; Excision; Exhibits; Exons; FDA approved; Gene Activation; Gene Expression; Genetic Transcription; Genome Stability; High-Throughput DNA Sequencing; Human; Infection; Inflammation; Inflammatory Response; Introns; Link; Lysine; Malignant Neoplasms; Maps; Mediating; Messenger RNA; Modeling; Modification; Molecular; Movement; Pathogenesis; Pathogenicity; Pathway interactions; Pattern; Pharmaceutical Preparations; Play; Poison; Positioning Attribute; RNA; RNA Polymerase II; RNA Processing; RNA Splicing; Reaction; Regulation; Research; Resistance; Role; Sepsis; Sepsis Syndrome; Source; Specificity; Spliced Genes; Spliceosomes; Superhelical DNA; Survival Rate; Testing; Therapeutic; Topoisomerase; Topoisomerase I inhibition; Topoisomerase-I Inhibitor; Topotecan; Transcription Initiation Site; Transcriptional Activation; Transcriptional Regulation; Type I DNA Topoisomerases; Variant; autism spectrum disorder; base; cancer cell; cancer therapy; carcinogenicity; cell killing; chromatin immunoprecipitation; cytotoxic; cytotoxicity; drug candidate; drug development; genome-wide; inhibitor/antagonist; innovation; insight; mutant; novel; novel strategies; novel therapeutics; prevent; promoter; protein protein interaction; recruit; therapeutic candidate; therapeutic target; tissue culture; tool; transcriptome sequencing; treatment strategy; virtual

Project Summary Topoisomerase I (TOP1) is a FDA-approved therapeutic target for late-stage cancers with a recently expanded therapeutic potential. Canonical TOP1 poisons, such as topotecan, kill rapidly dividing cells by preventing the release of TOP1 from DNA during its topoisomerase reaction to relax supercoiled DNA, leading to DNA breaks. However, it was recently discovered that TOP1 poisons also alter gene expression linked to autism spectrum disorders (ASD) and acute inflammatory response, among others, via a mechanism that is independent of DNA damage. Indeed, in addition to relaxing supercoiled DNA, TOP1 also regulates mRNA splicing and gene expression through its interaction with RNA polymerase II (RNAPII) and splicing factors. Therefore, new drugs that modulate the transcriptional function of TOP1 without causing DNA damage could greatly increase the therapeutic scope of TOP1, and provide treatment options for difficult diseases. However, the mechanisms linking TOP1 to mRNA regulation are not well established. Our recent discovery that SUMOylation of the lysine (K) residues 391 and 436 of TOP1 regulates its transcriptional function provides a crucial insight that will accelerate mechanistic advances. Due to this new insight, we are well-positioned to uncover the detailed molecular mechanism linking TOP1 and mRNA regulation. This proposal will first test a novel hypothesis that TOP1 K391/K436 SUMOylation regulates RNAPII movement and the coupling of RNAPII and spliceosome to facilitate gene transcription (Aim 1). We will evaluate the transcriptional landscape and splicing patterns, including the presence of splice variants that are dependent on TOP1 K391/K436 SUMOylation. We will identify additional cellular processes that may be altered by the inhibition of the TOP1 transcriptional function to uncover its full potential for new disease treatments (Aim 2). We will also develop a novel molecular strategy to disrupt the effects of TOP1 on mRNA regulation. This novel strategy will facilitate drug development for a wide range of disorders, including inflammation-induced sepsis and ASD. Finally, in addition to facilitating transcription, K391/K436 SUMOylation also suppresses TOP1 topoisomerase activity. Because the sensitivity to TOP1 poisons positively correlates with the level of TOP1 topoisomerase activity in cells, we will test an exciting possibility that transiently blocking TOP1 SUMOylation by this SUMOylation inhibitor could hypersensitize cells to TOP1 poisons during cancer chemotherapy (Aim 3).

项目摘要 拓扑异构酶I(TOP1)是FDA批准的晚期癌症的治疗靶点，最近扩大了 治疗潜力。典型的TOP1毒药，如拓扑替康，通过阻止细胞分裂而迅速杀死细胞 TOP1在其拓扑异构酶反应中从DNA中释放，以松弛超螺旋DNA，从而产生DNA 休息一下。然而，最近发现TOP1毒素也会改变与自闭症有关的基因表达 谱系障碍(ASD)和急性炎症反应等，通过一种 与DNA损伤无关。事实上，TOP1除了松弛超螺旋DNA外，还调节mRNAs 通过与RNA聚合酶II(RNAPII)和剪接因子的相互作用进行剪接和基因表达。 因此，在不造成DNA损伤的情况下调节TOP1转录功能的新药可能 大大扩大TOP1的治疗范围，为疑难疾病提供治疗选择。然而， TOP1与mRNA调控之间的联系机制还不是很清楚。我们最近的发现是 TOP1赖氨酸(K)残基391和436的总甲基化调节其转录功能提供了一种 关键的洞察力将加速机械化的进步。由于这一新的见解，我们处于有利地位， 揭示TOP1和mRNA调控之间的详细分子机制。这项提案将首先测试一个 TOP1 K391/K436糖基化调控RNAPII运动和RNAPII偶联的新假说 和剪接体以促进基因转录(目标1)。我们将评估转录情况，并 剪接模式，包括依赖于TOP1 K391/K436的剪接变体的存在 相扑化。我们将确定可能通过抑制TOP1而改变的其他细胞过程 转录功能，以揭示其在新疾病治疗方面的全部潜力(目标2)。我们还将开发一种 新的分子策略来破坏TOP1对mRNA调控的影响。这一新颖的战略将促进 针对多种疾病的药物开发，包括炎症引起的脓毒症和自闭症。最后，在 除了促进转录，K391/K436的SUMO化也抑制TOP1拓扑异构酶的活性。 因为对TOP1毒物的敏感性与TOP1拓扑异构酶活性水平呈正相关 细胞，我们将测试一种令人兴奋的可能性，即通过这种SUMO化暂时阻断TOP1的SUMO化 在癌症化疗过程中，抑制剂可使细胞对TOP1毒物超敏(Aim 3)。