Researchers at the Salk Institute for Biological Studies have
figured out that obesity sets the stage for diabetes through a
condition known as ER (endoplasmic reticulum) stress, which is
created by a high fat diet and overly activated in obese people,
triggering aberrant glucose production in the liver. The study,
which appears June 21 in the advanced online edition of Nature,
illustrates how the transcriptional switch CRTC2—that normally
teams up with the CREB protein to turn on the genes necessary to
increase glucose output—gets fixed in the on position in
insulin-resistant mice and begins to churn out too much glucose.
“When a cell starts to sense stress a red light goes on, which
slows down the production of proteins,” explains Marc Montminy,
Ph.D., a professor in the Clayton Foundation Laboratories for
Peptide Biology at the Salk Institute. “This process, which is
known as ER stress response, is abnormally active in livers of
obese individuals, where it contributes to the development of
hyperglycemia, o