Inhibition and Catalytic Degradation of Promutagenic DNA Deaminases

促诱变 DNA 脱氨酶的抑制和催化降解

基本信息

批准号：
10729968
负责人：
Rahul Manu Kohli
金额：
$ 18.99万
依托单位：
UNIVERSITY OF PENNSYLVANIA
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-07-06 至 2025-06-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10729968
关键词：
Address Binding Biology Breathing Catalogs Cell Line Cell Nucleus Cells Characteristics Chemicals Chimera organism Clinical Cyclization Cytidine Deaminase Cytoplasm Cytosine DNA DNA Damage DNA biosynthesis Deaminase Deamination Dinucleoside Phosphates Disease Distant Engineering Enzymes Exonuclease Family Family member Frequencies Future Genome Genomics Goals HIV Host Defense Immune In Vitro Knowledge Ligands Link Malignant - descriptor Malignant Neoplasms Mediating Molecular Molecular Probes Mutagenesis Mutate Mutation Nature Outcome Pathogenesis Pathologic Pathologic Mutagenesis Physiological Play Positioning Attribute Process Proteins Proteolysis Resistance Retroelements Retroviridae Risk Role Route Shapes Single-Stranded DNA Somatic Mutation Specificity Structural Models Structure Structure-Activity Relationship Technology Testing Therapeutic Time Ubiquitination Uracil Viral Virus Work Zebularine amino group antagonist base cancer cell cancer genome cancer initiation cancer type cellular engineering cytosine analog density design genetic approach improved inhibitor insight interest member meter mimicry multicatalytic endopeptidase complex nanomolar novel novel strategies nucleic acid delivery nucleic acid inhibitor preference protein degradation recruit response small molecule stem therapeutic target tool tumor tumor initiation tumor progression ubiquitin-protein ligase whole genome

项目摘要

PROJECT SUMMARY This proposal aims to develop the first potent and specific antagonists of the pro-mutagenic effects of APOBEC DNA deaminase enzymes in cells. Access to whole genome sequences has helped reveal common mutational signatures across various cancers. One such prominent mutational signature, termed SBS2, includes hypermutated clusters containing a high density of C to T/G substitutions on the same strand, a phenomenon known as kataegis. These features, in addition to the enrichment of the mutations in 5’-TC motifs, point to a causative role for APOBEC3 (A3) family enzymes. While these enzymes normally mutate and restrict retroviruses or retroelements, studies have confirmed that two family members, APOBEC3A (A3A) and APOBEC3B (A3B), have a prominent role in pathological mutagenesis targeting the host genome. The relative contributions of each enzyme remain a matter of vigorous debate, as genetic approaches specifically targeting A3A or A3B are limited by their high homology to one another and juxtaposition on the genome. Furthermore, no molecular tools currently exist that can disrupt A3 function. There is therefore a pressing need for molecular probes that can either inhibit or deplete A3 enzymes from cells. This proposal builds on the hypothesis that insights into the mechanism and substrate selectivity of A3 enzymes can be leveraged to design potent and specific antagonists. Specifically, we have demonstrated that mechanism-based inhibitor moieties can be presented in preferred secondary structures and engineered into exonuclease-resistant DNA molecules to yield potent nanomolar inhibitors of A3A. These molecules present the opportunity for facile functionalization, which can be utilized to convert classical inhibitors into molecules capable of inducing the catalytic degradation of the target APOBEC enzymes in cells, via an unprecedented combination of nucleic acid inhibitors and proteasome targeting (PROTAC) technology. Taken together, this proposal aims to fill a critical gap in the field by introducing tools to perturb APOBEC function in cells in order to reveal their underlying biology and offer a roadmap for potential therapeutics.

项目摘要该提案旨在发展Apobec的亲武力影响的第一个潜力和特定的拮抗剂细胞中的DNA脱氨酶。访问整个基因组序列有助于揭示常见的突变各种癌症的签名。一个这样的突出的突变签名称为SBS2，包括在同一链上包含高密度C到T/G取代的高密度的群集，这是一种现象被称为kataegis。这些特征，除了在5'-TC图案中富集突变外，还指向 APOBEC3（A3）家族酶的致病作用。这些酶通常会突变和限制逆转录病毒或追溯元素，研究证实了两个家庭成员Apobec3a（A3a）和 APOBEC3B（A3B）在靶向宿主基因组的病理诱变中具有重要作用。亲戚每个酶的贡献仍然是有力争议的问题，因为遗传方法专门针对 A3A或A3B受其高同源性的限制，并在基因组上并置。此外，目前没有任何可以破坏A3功能的分子工具。因此，对分子有压力可以抑制或替代细胞中A3酶的问题。该提议以这样的假设为基础可以利用对A3酶的机制和底物选择性的见解，以设计潜力和特定的拮抗剂。具体而言，我们已经证明了基于机制的抑制剂部分可以是以优选的二级结构呈现，并设计为耐核酸的DNA分子以产生 A3A的有效纳摩尔抑制剂。这些分子为便捷功能化提供了机会，可以用来将经典抑制剂转化为能够诱导催化降解的分子通过核酸抑制剂和蛋白酶体的前所未有的组合，细胞中的APOBEC酶靶向（PROTAC）技术。综上为了揭示其潜在的生物学并提供路线图潜在的治疗学。