Nice article. Here are a few key paragraphs that caught my eye…
The team tested what would happen when β-catenin was only partially impaired for signaling, finding that, in that case, the cells were unable to form bone or cartilage. After these tests, the scientists concluded that Wnt signaling is a determinant for bone formation, but that it isn’t sufficient for cartilage generation.
“We wanted to know what the factor was for cell fate determination,” said Dr. Maruyama. “What reprograms a cell to become cartilage if it isn’t Wnt signaling?”
This question led to a second major discovery: GATA 3, an alternative action of β-catenin responsible for skeletal cell fate switching. GATA3 is a single gene regulator, which turns on cartilage-specific gene expression in cells. “Basically,” said Dr. Wei Hsu, “GATA3 binds to the genome sequences required for the reprogramming. GATA3 is a game changer because we can use it to potentially change any somatic cell to become a cartilage-forming cell, similar to using four stem cell factors to generate embryonic stem cell-like cells called induced pluripotent stem cells (iPSC).”
Being able to control the cell fate in this way makes it possible to direct a cell to become bone, cartilage, or fat, which has tremendous implications for creating new treatments for the 1 in 4 people living with cartilage injuries and cartilage degeneration. There is currently no treatment that can regenerate cartilage, and current treatments are unable to improve joint function.