A Genetic Switch Plays Crucial Role In Muscle Stem Cells
New research published in Nature Cell Biology has revealed that a master muscle stem cell gene called Pax7 controls the development of new muscle tissue by regulating how certain genes are switched from a silent state to an active state.
As we walk, run, lift and stretch throughout the day, muscle stem cells called satellite cells help us repair minor muscle tears and build new muscle mass. Dr. Michael Rudnicki's group at the Sprott Centre for Stem Cell Research had previously shown that Pax7 controls this process by turning on muscle-specific genes such as Myf5, but until now it has not been clear how this happens.
The mystery has now been solved with their discovery that Pax7 recruits a protein complex to specific genes such as Myf5 that results in the genes being marked for switching on.
"By understanding the machinery that stem cells use to regulate their ability to form differentiated cells, we can work towards developing approaches to manipulate stem cells for therapeutic purposes," said Dr. Rudnicki, a Senior Scientist and Director of the Sprott Centre for Stem Cell Research and the Regenerative Medicine Program at the Ottawa Health Research Institute, and Professor in the Faculty of Medicine at the University of Ottawa.
This research was published in the advance online edition of Nature Cell Biology on December 9, 2007. It was funded by the National Institutes of Health, the Howard Hughes Medical Institute, the Canadian Institutes of Health Research and the Muscular Dystrophy Association.