北京大学定量生物学中心

学术报告

题 目：  Uncovering Macromolecule Conformation Ensembles with X-ray Scattering Interferometry

报告人： Xuesong Shi, PhD

      斯坦福大学生物化学系

时间：2016-5-26（周四），16:00-17:00

地点：北京大学老化学楼东配楼一层102会议室

主持人：汤超 教授

摘要:

  Biological macromolecules exist in solution as conformational ensembles that are described quantitatively by an energy landscape. In turn, a complete energy landscape can predict the dynamic behavior of proteins and nucleic acids responsible for their biological functions. Thus, a central challenge in modern biology is to accurately measure this conformation ensemble and to develop physical models that faithfully reproduce the underlying landscape. Recently, we developed a solution-phase scattering technique, small angle X-ray scattering interferometry (XSI), that provides the precise and instantaneous distance distribution in aqueous solution between a pair of Au-nanocrystal probes site-specifically conjugated to a biological macromolecule, thereby revealing the underlying macromolecule ensemble. We have applied XSI to interrogate the fundamental nature of the DNA double helix, to measure the effect of A-tract sequences on helix conformation and flexibility, to determine the structural plasticity of folded RNA structural motifs and their protein complexes, and to determine the conformational ensembles of model nucleic acids with a helix-junction-helix topology, including TAR RNA from HIV.

报告人简介：

石雪松博士，1995-1999年北京大学化学系本科，1999-2001加拿大皇后大学化学系硕士，2002-2007多伦多大学Pharmaceutical Sciences/Biophysical Chemistry专业博士。2007年2012年在斯坦福大学生化系博士后，后一直在斯坦福大学进行研究工作，先后担任研究助理和高级研究科学家。

石雪松博士在斯坦福期间的研究工作主要包括: 1) Develop novel biophysical and chemical biology techniques；2) RNA catalysis；3) Solution structure and dynamics of macromolecules。相关工作发表在NCB，PNAS，JACS等国际著名杂志上。