Researchers have better understanding of cellular pathways

CHICAGO, Oct. 28 (Xinhua) -- In an innovative study, researchers at the University of Chicago (UChicago) have demonstrated how a protein detects forces inside the cell and initiates a repair.

They screened proteins utilizing imagery and exquisitely sensitive assays developed in a lab. Computer programs allowed them to comb through the human genome to isolate proteins likely involved in the process.

A group called the LIM domain family of proteins appeared in the genome over 70 times, suggesting the importance of its conservation in human evolution.

Then in lab, the researchers applied a laser to act as an artificial way to mimic the damage done by the forces like stretching. They also added fluorescent tags to each of the LIM proteins and observed the process with high-powered microscopes. As soon as there was a tear or a rupture, they observed that many of the 70+ LIM domain proteins encoded by the human genome rapidly detected the damage and bound to the afflicted sites.

They also discovered this force-sensing via LIM is seen in both yeasts and mammals, suggesting it is an ancient function that evolution protected and propagated.

"Cellular force-sensing via LIM domains could inform many other processes besides self-repair, such as controlling stem cell fate, cell proliferation, or cell migration, and many more diverse signaling pathways that need further exploration," said Margaret Gardel, professor in the Department of Physics and the Pritzker School of Molecular Engineering at UChicago.

"The work furthers our understanding of fundamental science: how cells detect and process mechanical signals, how diverse mechanical pathways are regulated in epithelial cells and adherent tissues," said Gardel. "But there are also applications to building soft, responsive materials in a non-biological context that have a same recognition process."

The study, posted on UChicago's website on Tuesday, has been published in the Proceedings of the National Academy of Sciences.