A team of Monash researchers, lead by Professor Christophe Marcelle, have successfully identified the mechanism which causes stem cells to differentiate into specialised cells that form the muscular skeletal structure of animals. The research has since been published in the British scientific journal, Nature.

 

The discovery by Professor Marcellle’s team is part of a broader international effort to identify the complex molecular process that cause stem cell embryos to differentiate and form different cells as disparate as muscle or individual nerve cells.

 

The process of differentiation occurs soon after fertilization, when rapid growth and development of fetuses require fast development of cells.

 

Using the muscular stem cells in chicken fetuses, Professor Marcelle’s team were able to investigate the effect of a known signaling pathway called NOTCH on muscle differentiation. They found that differentiation of stem cells to muscle was initiated when NOTCH signaling proteins touched some of the cells. These proteins were carried by passing cells migrating from a different tissue, the neural crest, known as the the progenitor tissue of sensory nerve cells. Muscle formation in the target stem cells occurred only when the NOTCH pathway was triggered briefly by the migrating neural crest cells.

 

“This kiss-and-run activation of a pathway is a completely novel mechanism of stem cell specification which explains why only some stem cells adopt a muscle cell fate,” said team member and the paper’s lead author, Anne Rios.

 

Professor Marcelle said that more than 2 per cent of the population was affected by muscle dysfunction. “Muscle frailty in ageing and disease imposes a huge economic burden, so it is critical to explore novel avenues of research that could lead to new treatments,” he said.

 

He said the team would now focus on unraveling the mechanisms of embryonic muscle cell differentiation at the molecular level as a necessary step to regulating regeneration of the muscles in human patients.