Using a combination of molecular compounds that are commonly used in stem-cell research called Yamanaka factors, researchers found the regeneration of muscle tissue was prevalent among mice. Yamanaka factors are a group of proteins which play a vital role in the creation of induced pluripotent stem cells (cells that have the ability to become any cell in the body), often called iPSCs. They control how DNA is copied for translation into other proteins and are used to convert specialized cells, like skin cells, into more stem-cell-like cells that are pluripotent.
Myogenic progenitor cells, also known as satellite cells or myoblasts, possess the ability to differentiate into large multinucleated myotubes (muscle fibers) to provide a cell culture model of mature skeletal myofibers. “Loss of these progenitors has been connected to age-related muscle degeneration,” says Salk Professor.
The primary role of these progenitor cells is to replace dead or damaged cells. In this way, progenitor cells are necessary for repair after injury and as part of ongoing tissue maintenance. Using the combination of Yamanaka factors to create these special muscle building tissues will allow for muscle repair to be quicker, easier, and available to everyone. This will allow any cell to be turned into a muscle repair cell.
In the study, researchers found that adding the Yamanaka factors accelerated muscle regeneration in mice by also reducing the levels of a protein called Wnt4, which then activated the satellite cells to be turned into muscle repair cells. We could potentially use this technology to either directly reduce Wnt4 levels in skeletal muscle or to block the communication between Wnt4 and muscle stem cells.
In our class, we have learned about the different jobs of proteins and how some some of these functions are positive (such as the creation of collagen) and negative to cells. WNT4 in this case researchers analyzed are bad for muscle development in creating structure of muscles but can be stopped with the help of Yamanaka factors. Similar to chaperonins, Yamanaka factors allow for the replication of proteins to be easier by controlling how DNA is copied in these myogenic progenitor cells.