Researchers report protein interactions of MAP kinase signaling pathway

The Stowers Institute's Rong Li Lab, in collaboration with the Institute's Imaging Center, has achieved a quantitative in vivo measurement of the dynamic protein-protein interactions in the mitogen-activated protein (MAP) kinase cascade signaling pathway, which is critical to growth and differentiation decisions in all eukaryotic cells.

The paper, “Mapping Dynamic Protein Interactions in the MAP Kinase Signaling Using Live-Cell Fluorescence Fluctuation Spectroscopy and Imaging,” was posted to the Web site of Proceedings of the National Academy of Sciences (PNAS) yesterday and will appear in a future print issue of the journal.

In this work, Brian Slaughter, Ph.D., Postdoctoral Research Fellow; Joel Schwartz, Ph.D., Managing Director of the Imaging Center; and Rong Li, Ph.D., Investigator, used sophisticated biophysical techniques to perform quantitative biochemical measurements directly in live yeast cells.

“It turns out that by using three fluorescence-based analyses we could assess the movement, concentration, and state of protein hetero- and homo-oligomerization at the single cell level,” said Dr. Slaughter. “It is a significant advance to be able to apply these quantitative techniques to the model system of yeast.”

“These technical breakthroughs represent an exciting emerging direction for molecular analysis in the future,” said Dr. Li. “They will enable biological systems to be understood with precise information regarding when, where, and to what extent molecules interact with each other during important regulatory processes.”

The Rong Li lab worked closely with the Institute's Imaging Center to perfect the application of these techniques in yeast, calling on the Center's expertise and cutting-edge instrumentation for microscopy-based technology.

“This work demonstrates the Institute's tremendous strength for live-cell quantitative analysis,” said Robb Krumlauf, Ph.D., Scientific Director. “I believe this and similar techniques will become increasingly important to our ability to better understand the most fundamental events in the life cycle of a cell.”