Office of Science Researcher Creates System that Visualizes the Production of Single Proteins in Live Cells


In the March 16, 2006, issue of the journal Nature, Professor Sunney Xie, Harvard University, describes a new imaging approach that allows the tracking of the production of individual proteins in a single living cell. The fluorescence-based technique will permit the study of the expression of many important proteins in the cell, including those produced in low numbers. In the Nature article, Dr. Xie was able to make quantitative measurements and observe protein production as a stochastic process, a series of discrete events recognizable as bursts of fluorescent molecules. This new technique improves upon standard techniques because it can visualize distinct biological steps while the standard approach is limited to measuring the combined average of these events. A unique aspect of this imaging technique isolates single cells in their own microfluidic compartments, thus improving the sensitivity of the fluorescent signal of each newly-synthesized protein. The research was supported by Genomics:GTL funding for the development of imaging techniques for the study of microbial molecular machines and cellular biology.