BACKGROUND
Pluripotent stem cells, by definition, can become any type of cell in the body, but researchers have struggled to guide them to produce certain tissues, including muscle. In developing human embryos, muscle cells — as well as the bone and cartilage of vertebrae and ribs, among other cell types — arise from small clusters of cells called somites.
Researchers have studied how somites develop in animals and identified the molecules that seem to be an important part of that process in animals. But when scientists have tried to use those molecules to coax human stem cells to generate somites, the protocols have been inefficient.
METHOD
The scientists isolated the minuscule developing human somites and measured expression levels of different genes both before and after the somites were fully formed. For each gene that changed levels during the process, the researchers tested whether adding molecules to boost or suppress the function of that gene in human pluripotent stem cells helped push the cells to become
The scientists followed the cells over the next four weeks and determined that they were indeed able to generate cells including skeletal muscle, bone and cartilage that normally develop from somites.
IMPACT
The new protocol to create
AUTHORS
Pyle is a UCLA associate professor of microbiology, immunology and molecular genetics. The first author of the study is Haibin Xi;
