Structural Determination and Design of Drug Interactions with Ribonucleotide Reductase

药物与核糖核苷酸还原酶相互作用的结构测定和设计

• 批准号: 10471817
• 负责人: KELSEY Rose MILLER
• 金额: $ 6.76万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10471817
• 关键词: Active Sites; Address; Affinity; Anabolism; Binding; Binding Sites; Biological Assay; Catalysis; Cells; Characteristics; Cladribine; Clinical; Clofarabine; Complex; Cryoelectron Microscopy; DNA; DNA Repair; DNA biosynthesis; Data; Deoxyribonucleotides; Development; Drug Design; Drug Interactions; Drug Targeting; Effectiveness; Electron Microscopy; Electrons; Enzymes; Equilibrium; FDA approved; Failure; Goals; Halogens; Health; Human; Image; Impairment; Knowledge; Lead; Libraries; Literature; Location; Malignant Neoplasms; Methods; Molecular Conformation; Mutagenesis; Negative Staining; Nucleotides; Organism; Pharmaceutical Preparations; Play; Property; Reaction; Resolution; Ribonucleotide Reductase; Ribonucleotide Reductase Inhibitor; Ribonucleotides; Roentgen Rays; Role; Site; Source; Specificity; Structure; Testing; Ultrafiltration; Work; base; cancer therapy; cancer type; cofactor; comparative; deoxyribonucleoside triphosphate; design; experimental study; fludarabine; genome integrity; inhibitor; insight; metal chelator; nucleoside analog; nucleoside inhibitor; prevent; response; small molecule; therapeutic target; trend; tripolyphosphate

PROJECT SUMMARY/ABSTRACT The equilibrium of deoxyribonucleoside triphosphates (dNTPs), the building blocks of DNA, is critical for maintaining human health. Known as the regulator of dNTP biosynthesis, ribonucleotide reductases (RNRs) are essential enzymes found in all organisms that catalyze the reduction of ribonucleotides to deoxyribonucleotides, an essential reaction for DNA replication and repair. Failure of cells to maintain appropriate dNTP concentrations can lead to increased mutagenesis and uncontrolled proliferation, characteristics that promote cancer development. RNR inhibition has been implicated in several types of cancers and is a target for drug design. Although current drugs in clinical use are effective, our understanding of the inhibition mechanism is incomplete. Specifically, nucleoside analogs are used as α-inhibitors and have been shown to cause a distinct conformational change upon addition to the RNR α-subunit. Upon addition of nucleoside analogs, α-hexamer rings are formed. α-hexamerization has been observed with three triphosphorylated nucleoside analogs, clofarabine, cladribine and fludarabine; however, there are no near- atomic resolution structures available. The work described in this proposal aims to obtain high resolution structures of each α-inhibitor with Human RNR and to design and evaluate new RNR α-inhibitors. Cryo- electron microscopy will be used to examine the structures of α-hexamers after addition of triphosphorylated cladribine, clofarabine, and fludarabine to determine α-inhibitor binding locations, possible conformational changes and noncovalent interactions that could explain α-hexamer stability, and how α-hexamerization prevents RNR activity. Furthermore, new nucleoside analogs will be designed with the goal of increasing binding affinity of the nucleoside analogs to study the effects of electronic properties on the stability of α- hexamers. Together, this work aims to deepen our understanding of the mechanism of RNR inhibition by understanding the formation of α-hexamers and utilize structure-based drug design to expand the library of nucleoside analogs that can induce α-hexamerization.

项目总结/文摘