CAREER: Interface-induced misfolding and aggregation of intrinsically disordered proteins

职业：界面诱导的本质无序蛋白质的错误折叠和聚集

• 批准号: 1150855
• 负责人: Eva Chi
• 金额: $ 40万
• 依托单位: University of New Mexico
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1150855&HistoricalAwards=false
• 关键词: CAREER; Interface; induced; misfolding; aggregation

Chi, EvaCBET - 1150855 Intellectual MeritNON-TECHNICAL:Despite the implication of intrinsically disordered proteins (IDPs) in a number of human diseases, the aggregation mechanism of IDP by which the disease develops remains poorly understood. The objective of this proposal is to gain a fundamental understanding of how interfaces in the cellular environment can affect the misfolding and aggregation of IDPs. The PI will investigate the aggregation of two IDPs implicated in Alzheimer¡¦s disease (AD), the amyloid-£] (A£]) peptide and the tau protein. Successful completion of the proposed research will advance current understanding of not only the interfacial effects on the structural dynamics of an important class of proteins, but also of the mechanism and thermodynamic driving forces underlying the pathogenesis of neurodegenerative diseases.TECHNICAL:The PI proposes a novel aggregation mechanism in which an IDP first forms an aggregation-competent intermediate that is partially folded and proceeds through a structurally contracted transition state. This step is followed by the assembly of intermediates to form larger aggregates. The PI hypothesizes that interfaces can induce IDP structural compaction, lowering the activation free energy of aggregation and template nucleation. The PI further hypothesizes that these interfacial effects are significantly amplified under conditions that mimic the cell milieu, namely, macromolecular crowding and the presence of osmolytes. The PI hypothesizes that attenuating the binding of A£]'n peptide and tau protein to biological interfaces can inhibit their aggregation and toxicity. To test these hypotheses, the PI proposes the following three objectives that build on her research group¡¦s unique strengths in thermodynamics of protein aggregation, biophysical analysis of proteins in solution and at interfaces, and biochemistry. The PI proposes to accomplish the following three research objectives: 1) to evaluate the likelihood and affinity of four tau proteins to partition to two interfaces, the air/water interface and the lipid membrane interface, and characterize changes in tau structure and aggregation kinetics accompanying the binding of the proteins to the interfaces; 2) to study the effect of molecular crowding and osmolytes on A£]'nand tau¡¦s surface activity, membrane interaction, and aggregation to test if interfacial forces stemming from excluded volume and preferential exclusion can modulate interface-templated IDP aggregation; 3) to investigate whether attenuation of the binding of A£]'nand tau to lipid membranes can ameliorate their aggregation and toxicity.Broader Impacts The proposed research, deeply rooted in molecular thermodynamics and interface science, represents a novel approach to studying the aggregation of IDPs. The analysis of intermolecular interactions and interfacial forces that govern the assembly of IDPs represents a fundamental scientific challenge that is of great importance in biology and medicine. Understanding of the mechanism and thermodynamic driving forces of IDP aggregation gained from the proposed study is of paramount importance in advancing the current knowledge of the molecular mechanism underlying the pathogenesis of Alzheimer¡¦s disease. Determining the aggregation mechanism of IDPs could potentially lead to therapeutic strategies for treating such neurodegenerative diseases. In terms of education, the PI is committed to furthering her contribution to the establishment of New Mexico¡¦s first Biomedical Engineering undergraduate and graduate degree programs through new course development and student recruitment. The PI is also strongly dedicated to expanding and augmenting the existing outreach efforts at the University of New Mexico to rural Native American elementary schools and introducing a new hands-on demonstration module focusing on the molecular aspects of protein structure and denaturation to Albuquerque High School students. The PI will continue mentoring efforts to Native American students from the Southwest Indian Polytechnic Institute helping them make a successful transition to the University of New Mexico. The cumulative and long-term impact of the proposed educational and outreach efforts will be increased enrollment and retention of students in bioengineering, particularly underrepresented minorities and women, which will spark economic vitality and meet future work force demands in New Mexico and beyond.

Chi，evacbet -1150855智力精美技术：尽管本质上无序的蛋白质（IDP）在许多人类疾病中暗示了IDP的聚集机制，但该疾病发展的聚集机制仍然知之甚少。该提案的目的是对细胞环境中的界面如何影响IDP的错误折叠和聚集有基本的了解。 PI将研究在阿尔茨海默氏病（AD），淀粉样蛋白£]（a£]）胡椒和tau蛋白的两个IDP的聚集。成功完成拟议的研究的成功完成将不仅对重要蛋白质的结构动力学的影响进行当前的理解，还可以提高对神经退行性疾病发病机理的机制和热力学驱动力的机制和热力学驱动力的影响。技术疾病的发病机理。技术：PI通过IDP进行了一种新型聚集机制，该机制是一种既定的构造机制，该机制是构造的，该机制是相互作用的，该机制既可以构成相互作用的组成型，又是构造的，该机制既是构造的，又可以构成相互作用的构造。合同过渡状态。此步骤之后是中间体组装以形成较大的聚集体。 PI假设接口可以诱导IDP结构压实，从而降低聚集和模板成核的激活自由能。 PI进一步假设，这些界面作用在模仿细胞环境的条件下显着放大，即大分子拥挤和渗透剂的存在。 PI假设，削弱了£]'n o和tau蛋白与生物界面的结合可以抑制它们的聚集和毒性。为了检验这些假设，PI提出了以下三个目标，这些目标是基于她的研究小组的独特优势，在蛋白质聚集的热力学，溶液和界面中蛋白质的生物物理分析以及生物化学。 PI提出的提议要实现以下三个研究目标：1）评估四种Tau蛋白的可能性和亲和力，分配到两个接口，即空气/水接口和脂质膜界面，并表征Tau结构的变化，并参与蛋白质与互发的结合； 2）研究分子拥挤和渗透剂对£] nand tau的表面活性，膜相互作用和聚集的影响，以测试是否因排除体积和优先排除而产生的界面力是否可以调节界面 - 接口的IDP聚集； 3）研究£]'''''nand tau对脂质膜的结合是否可以改善其聚集和毒性。Broader影响了所提出的研究，深深地植根于分子热力学和界面科学，代表了研究IDPS聚集的新方法。对IDP的组装的分子间相互作用和界面力的分析代表了一项基本的科学挑战，在生物学和医学中非常重要。了解从拟议的研究中获得的IDP聚集的机制和热力学驱动力对于促进当前对阿尔茨海默氏病发病机理的分子机制的知识至关重要。确定IDP的聚集机制可能会导致治疗这种神经退行性疾病的治疗策略。在教育方面，PI致力于通过新的课程开发和学生招聘，为建立新墨西哥州的建立贡献。 PI还强烈致力于扩大和扩大新墨西哥大学的现有外展活动，并向艰难的美国原住民小学，并引入了一个新的动手示范模块，该模块重点介绍了蛋白质结构和变性的分子方面，并向Albuquerque高中生。 PI将继续向来自西南印度理工学院的美洲原住民学生进行指导努力，以帮助他们成功过渡到新墨西哥大学。拟议的教育和推广工作对拟议的教育和外展工作的累积和长期影响将增加生物工程的学生的入学率和保留，特别是代表人数不足的少数民族和妇女，这将激发经济活力并满足新墨西哥州及其他地区的未来劳动力需求。