Scientists in Australia say they have identified a previously unseen way the body controls stored sugar, showing that ubiquitin—a molecule best known for tagging damaged proteins—can also attach directly to glycogen to regulate its breakdown, according to a research published by Nature. They described the finding as overturning decades of accepted biology and opening a path to therapies that reduce sugar accumulation at its source.
Glycogen carried more ubiquitin “tags” in mice during fasting, when glycogen levels dropped, indicating that sugar processing requires the molecule. This paves the path for new forms of treatment strategies for conditions marked by excessive glycogen, including diabetes, obesity, and liver and heart disease, according to press release published on EurekAlert.
Regulation on demand
“It’s quite likely biology books will need to be amended as a result of our findings,” said Professor David Komander. He added that the work reveals “a second pathway where glycogen can be directly regulated—likely on demand.”
The discovery relied on a new method which enabled the researchers to visualize the sugar-tagging process in animal models and human cells. Ubiquitin’s role in linking to a sugar molecule rather than a protein marks an expansion of what scientists have believed the molecule could do. The researchers characterized ubiquitin as “the kiss of death” for unwanted proteins, The Sydney Morning Herald reported.
A hormone driving weight loss
In a separate finding, researchers in the USA reported that a naturally occurring hormone, FGF21, appears to drive weight loss by signaling to the hindbrain to raise metabolic rate, according to a university press release. They said it targets the same region as GLP-1 drugs while working through a different mechanism. The researchers found that this increases energy expenditure rather than primarily suppressing appetite.
according to Fox News. “We hope that by identifying the specific circuit, it can help in the creation of more targeted therapies that are effective without negative side effects,” said lead author Matthew Potthoff.