Synthetic glycosaminoglycan mimetics as regulators of megakaryopoiesis and thrombopoiesis

作为巨核细胞生成和血小板生成调节剂的合成糖胺聚糖模拟物

• 批准号: 10558574
• 负责人: Daniel Kwame Afosah
• 金额: $ 17.94万
• 依托单位: VIRGINIA COMMONWEALTH UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-02-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10558574
• 关键词: Advanced Development; Advisory Committees; Affinity; Binding; Binding Proteins; Biological; Biological Assay; Biology; Biopolymers; Blood; Blood Circulation; Blood Platelets; Bone Marrow; Career Choice; Charge; Chemicals; Coagulation Process; Complex; Coupled; Crystallography; Cytoplasm; Data; Development; Development Plans; Dimerization; Disease; Drug Targeting; Ensure; Environment; Excision; Extracellular Matrix; Flavonoids; Foundations; Funding; Generations; Glycosaminoglycans; Hematopoietic stem cells; Heparitin Sulfate; Human; ITIM; In Vitro; Inflammation; Length; Letters; Libraries; Malignant Neoplasms; Megakaryocytes; Megakaryocytopoieses; Mentored Clinical Scientist Development Program; Mentors; Mentorship; Mission; Molecular; Mus; National Heart, Lung, and Blood Institute; Nature; Organic Synthesis; Outcome; Pattern; Pharmaceutical Preparations; Photoaffinity Labels; Plasma; Platelet Count measurement; Play; Postdoctoral Fellow; Preparation; Process; Production; Proteins; Proteomics; Public Health; Records; Regulation; Research; Research Personnel; Research Proposals; Research Training; Resources; Role; Signal Transduction; Stream; Structure; Structure-Activity Relationship; Sulfate; Surface Plasmon Resonance; Therapeutic; Therapeutic Agents; Thrombocytopenia; Thrombopoiesis; Thrombosis; United States National Institutes of Health; Validation; X-Ray Crystallography; analog; analytical ultracentrifugation; biomacromolecule; biophysical analysis; biophysical techniques; career; career development; chemical property; computer studies; experience; functional mimics; high throughput screening; in vivo; innovation; member; mimetics; molecular modeling; novel; prevent; promoter; receptor; scaffold; screening; skills; small molecule; small molecule libraries; stem; sugar; therapeutic development; three dimensional structure

PROJECT SUMMARY Title: Synthetic glycosaminoglycan mimetics as regulators of megakaryopoiesis and thrombopoiesis. Key Words: Platelets, Glycosaminoglycans, thrombopoiesis, G6b-B, NSGMs The Candidate is an NIH K12 postdoctoral scholar on an academic career path. His focus is on the roles of glycosaminoglycans (GAGs) in thrombopoiesis. He has significant research experience studying GAG–protein interactions, and a strong background in organic synthesis notably, the preparation of aromatic-scaffold-based GAG mimetics known as non-saccharide GAG mimetics (NSGMs), which are functional mimics of GAGs. Career Development Plan: This proposal is well structured and involves 2 years of mentored research training, which will ensure that the candidate develops advanced research skills critical for an independent academic career. He has assembled an advisory committee of experienced and well-funded PIs, with proven track records of mentoring young academic researchers. He also has a well-resourced environment for the proposed research. Research Plan: The number of circulating platelets is tightly balanced through continuous production and removal of platelets to prevent potentially detrimental thrombosis. Platelets are produced through sequential processes, wherein hematopoietic stem cells commit to the formation of megakaryocytes (megakaryopoiesis), which release cytoplasmic extensions into the blood stream to produce platelets (thrombopoiesis). While some mechanisms and molecular regulators of these process have been identified, much remains to be elucidated. Of these, the roles of extracellular matrix and GAGs are poorly characterized. Although GAGs are regulators of various proteins, their heterogeneous nature and the challenges associated with obtaining homogeneous forms of these complex biomacromolecules remain bottlenecks for elucidating their biological roles. Our lab has developed a diverse chemical library of NSGMs which possess an aromatic scaffold carrying multiple sulfate groups mimicking the sulfated sugar scaffold of GAGs. NSGMs bind and selectively modulate several GAG- binding proteins involved in diseases, and thus serve as excellent chemical biology probes of GAG function. We have identified G4.1, a flavonoid-based NSGM as having potent thrombopoietic potential in vitro and in vivo. Our preliminary studies show that G4.1 binds with high affinity to G6b-B, an inhibitory receptor found on megakaryocytes and platelets, involved in the regulation of platelet production. Our studies also show that G4.1 promotes G6b-B dimerization, which is required for downstream signaling. Based on this data, we hypothesize that, G4.1 promotes thrombopoiesis, in part, by its highly selective interaction with G6b-B. We will determine the nature of the interaction of G4.1 with G6b-B, probe the selectivity of G4.1 for G6b-B, and elucidate the structure- activity-relationship (SAR) of this class of compounds. This research proposal benefits from; 1) the candidate’s personal track-record, 2) robust preliminary data, 3) a highly experienced advisory committee with relevant expertise to the proposed research, and 4) a supportive and well-resourced research environment. The three aims of the proposal are : I) Determine the nature of interaction of G4.1 with G6b-B, II) Evaluate the selectivity of G4.1 recognition of G6b-B, and III) Synthesize a library of G4.1 analogs and elucidate SAR.

项目摘要 标题：合成糖胺聚糖模拟物作为巨核细胞生成和血小板生成的调节剂。 关键词：血小板，糖胺聚糖，血小板生成，G6 b-B，NSGMs 候选人是NIH K12博士后学者，正在走学术生涯道路。他的重点是以下角色： 糖胺聚糖（GAG）在血小板生成中的作用。他在研究GAG蛋白方面有着丰富的研究经验 相互作用，以及有机合成的强大背景，特别是芳香族支架的制备， GAG模拟物称为非糖GAG模拟物（NSGM），其是GAG的功能模拟物。职业生涯 发展计划：该提案结构合理，涉及2年的指导研究培训， 将确保候选人发展先进的研究技能，这对独立的学术生涯至关重要。 他组建了一个由经验丰富、资金充足的私人侦探组成的咨询委员会， 指导年轻的学术研究人员。他还为拟议的研究提供了一个资源充足的环境。 研究计划：通过连续生产， 去除血小板以防止潜在的有害血栓形成。血小板是通过连续的 过程，其中造血干细胞致力于形成巨核细胞（巨核细胞生成）， 其将细胞质延伸物释放到血流中以产生血小板（血小板生成）。虽然一些 这些过程的机制和分子调节剂已被确定，仍有许多有待阐明。的 因此，细胞外基质和糖胺聚糖的作用还不清楚。虽然GAGs是监管机构， 各种蛋白质，它们的异质性以及与获得同质形式相关的挑战 这些复杂的生物大分子仍然是阐明其生物学作用的瓶颈。我们的实验室 开发了具有携带多个硫酸根的芳香族支架的NSGMs的多样化化学文库 模拟GAG的硫酸化糖支架的基团。NSGM结合并选择性调节几种GAG- 结合蛋白，因此可作为GAG功能的优良化学生物学探针。我们 已经鉴定了G4.1，一种基于类黄酮的NSGM，在体外和体内具有有效的血小板生成潜力。我们 初步研究表明，G4.1与G6 b-B结合具有高亲和力，G6 b-B是在 巨核细胞和血小板，参与血小板产生的调节。我们的研究还表明，G4.1 促进下游信号传导所需的G6 b-B二聚化。基于这些数据，我们假设 G4.1促进血小板生成，部分是通过其与G6 b-B的高度选择性相互作用。康贝特人将以 G4.1与G6 b-B相互作用的性质，探测G4.1对G6 b-B的选择性，并阐明结构- 活性关系（SAR）这类化合物。本研究计划受益于：1）候选人的 个人跟踪记录，2）可靠的初步数据，3）经验丰富的咨询委员会， 专业知识，以拟议的研究，和4）支持和资源充足的研究环境。三 该提案的目的是：I）确定G4.1与G6 b-B相互作用的性质，II）评估选择性 III）合成G4.1类似物的文库并阐明SAR。