Rotation of Single Cell Surface Protein Molecules Studied via Nanoparticle Probes

通过纳米颗粒探针研究单细胞表面蛋白质分子的旋转

• 批准号: 1024668
• 负责人: B.George Barisas
• 金额: $ 61.11万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1024668&HistoricalAwards=false
• 关键词: Rotation; Single; Cell; Surface; Protein

Modern optical methods have allowed researchers to determine many properties of single biological molecules, including those on the surfaces of living cells. Evaluating how two molecules of the exact same type can differ in their behavior has enhanced understanding of cellular function. However, one important property of individual molecules, their rates of rotation, has so far escaped characterization since this rotation is extremely rapid, occurring in thousandths of a second or less. Nonetheless rotation of cell surface molecules, particularly proteins, is important since changes in these motions reflect how cells obtain information from their environment. Nanotechnology has recently provided a variety of tags that can be attached to cell surface molecules to provide optical signals from individual biomolecules. This project will employ two of these, nanometer sized cylindrical gold nanorods and eggshaped fluorescent structures called quantum dots, to determine time-dependent orientational changes, and hence rotation rates, of the individual molecules to which they are attached. These single-molecule results will be applied to questions that previous measurements averaging properties of large numbers of molecules together have left unresolved. An example, one such question concerns the actual sizes of large cell surface molecular complexes that initiate particular biological effects. Broader impactsThis project will provide Ph.D. educational opportunities to minority, first-generation and female college students in a laboratory that already trains a diverse group of scientists. This group has included women, under-represented minority individuals and first-generation and non-traditional college students at the undergraduate, graduate and postdoctoral levels. The project activities will broaden the exposure of students and trainees to important contemporary topics such as nanotechnology and singlemolecule biophysics. Instrumental resources developed through the project will be available to visiting scientists and to undergraduate researchers and will provide a significant infrastructural resource for biological research, in particular, unique facilities for measuring motions of biological molecules. Such studies will, as have previous investigations by this laboratory, lead to specialized sessions at the U.S. Biophysical Society meetings, short courses in international locations, and laboratory modules in optical biophysical methods for university students. One societal benefit of the project will be improved understanding of mechanisms limiting reproductive efficiency of livestock since one of the topics to be addressed arises from unresolved questions in this area.

现代光学方法使研究人员能够确定单个生物分子的许多特性，包括活细胞表面的分子。评估两种完全相同类型的分子在行为上的差异增强了对细胞功能的理解。然而，单个分子的一个重要特性，即它们的旋转速率，迄今为止还没有被描述，因为这种旋转非常快，发生在千分之一秒或更短的时间内。然而，细胞表面分子，特别是蛋白质的旋转是重要的，因为这些运动的变化反映了细胞如何从环境中获取信息。纳米技术最近提供了各种标签，可以附着在细胞表面分子上，以提供来自单个生物分子的光学信号。该项目将采用其中的两种，纳米尺寸的圆柱形金纳米棒和称为量子点的蛋形荧光结构，以确定它们所连接的单个分子的随时间变化的取向变化，从而确定旋转速率。这些单分子的结果将被应用到以前的测量平均大量分子的性质在一起没有解决的问题。例如，其中一个问题涉及启动特定生物学效应的大细胞表面分子复合物的实际大小。更广泛的影响这个项目将提供博士学位。在一个已经培养了一批不同科学家的实验室里，为少数民族、第一代和女大学生提供教育机会。这一群体包括妇女、代表性不足的少数民族个人以及第一代和非传统的本科生、研究生和博士后学生。项目活动将扩大学生和受训人员对纳米技术和单分子生物物理学等重要当代课题的接触。通过该项目开发的仪器资源将提供给访问科学家和本科生研究人员，并将为生物研究提供重要的基础设施资源，特别是测量生物分子运动的独特设施。这些研究将，如本实验室以前的调查，导致在美国生物物理学会会议，短期课程在国际地点，并在光学生物物理方法的大学生实验室模块的专业会议。该项目的一个社会效益是提高对限制牲畜繁殖效率的机制的认识，因为要解决的一个问题来自这一领域尚未解决的问题。