Proteins in Motion: Measuring Disorder and Interactions at Single Molecule Level

在分子水平上理解生命是现代科学的重大挑战之一。这将为社会带来重大利益，包括更好的药物和治疗疾病的新思路，仿生纳米技术的设计和创新医学成像方法的发展。Gradinaru生物物理研究实验室正在开发先进的光学检测技术，用于精确测量单个生物分子的构象和相互作用动力学。单分子方法在生物学中已经变得流行，因为它们可以捕获分子状态和过程，而不会由于系综平均而丢失信息。我们设计并建立了显微镜，通过智能检测和数据分析单个荧光探针发射的单个光子，同时记录多种光学特性。这台功能强大、灵敏度高的仪器将进一步完善，并应用于几种动态蛋白质复合物的研究。我们将研究如何合理设计的小分子药物可以抑制STAT信号蛋白的癌症活性，并将表征无序蛋白质的结构波动，以了解它们对生物活性的作用。从长远来看，单分子方法也将应用于复杂的变构膜蛋白，如环核苷酸门控通道，以确定聚集在信号转导中的作用以及配体结合，构象动力学和通道激活之间的关系。与我们合作小组的数据相印证，这项雄心勃勃的研究计划可能会导致针对影响加拿大人口的血癌，心脏病和神经退行性疾病的新疗法。

Understanding life at molecular level is one of the great challenges in modern science. This will bring major benefits to society, including new ideas for better drugs and therapies against diseases, the design of bio-mimetic nanotechnology and the development of innovative medical imaging methods. Gradinaru biophysics research laboratory is developing advanced optical detection techniques for precision measurements of conformation and interaction dynamics of individual biological molecules. Single-molecule methods have become popular in biology because they can capture molecular states and processes without loss of information due to ensemble averaging. We designed and set up microscopes that record multiple optical properties simultaneously though intelligent detection and data analysis of single photons emitted by single fluorescent probes. This very powerful and sensitive equipment will be further improved and applied to the study of several dynamic protein complexes. We will investigate how rationally-designed small-molecule drugs can inhibit the cancer activity of STAT signalling proteins and will characterize structural fluctuations in disordered proteins in order to understand their role for biological activity. In the long term, single-molecule approaches will also be applied to complex allosteric membrane proteins, such as the cyclic nucleotide gated channels, to determine the role of aggregation in signal transduction and the relationship between ligand binding, conformational dynamics and channel activation. Corroborated with data from our collaborating groups, this ambitious research plan could lead to new therapies against blood cancers, heart and neurodegenerative diseases affecting the Canadian population.