A key step in metabolic pathways linked to diabetes and cancer has been identified by American and Japanese researchers.
TORC 2 activates a protein called Akt, which plays a crucial role in how cells respond to insulin, said Kazuo Shiozaki, of the University of California.
Normally, insulin triggers fat and muscle cells to take up sugar from the blood. Patients with type II diabetes make plenty of insulin, but their cells do not respond to it properly.
Akt plays a role in the series of steps between insulin exposure and sugar uptake; specifically, it causes proteins that take sugar from the blood to move to the cell surface.
Mice that lack the gene for Akt develop diabetes-like symptoms.
"We know that Akt is a key player in diabetes, so we are trying to work upstream from there," said Shiozaki.
Akt also controls cell growth in early embryos and can promote the growth of cancer cells, he added.
Shiozaki and colleagues studied TORC 2 in yeast.
They found that a protein called Ryh1, when bound to another molecule called guanosine triphosphate, is needed to activate TORC 2.
"Our discovery suggests that the early and late steps in insulin response are closely linked to each other," said Shiozaki.
The study was published online in the journal Current Biology.