The study by researchers in the School of Life Sciences at Arizona State University not only adds to understanding about bees, but also adds insights into our own development and aging.
A female bee can become either a worker or a queen. Queen bees are larger and live longer than workers. Queen bees are also fertile while workers are essentially sterile. A queen has only one role-to lay eggs-while workers tend the hive, care for the queen and larvae, and forage for food.
"The incredible thing is that both of these types of female honeybees emerge from the same genome. So how does that happen?" said Florian Wolschin, lead author of the study.
Workers determine the fate of the larvae by what they feed them.
The amount and composition of food that the larvae receive determine whether they become workers or queens.
People have known this for many years, but exactly what happens inside the cells to create this split isn't completely clear.
The researchers found that the insulin signalling pathway plays a role in caste development.
Insulin is a hormone found in humans and many other animals, and insulin-like peptides have been discovered in bees.
Insulin moves glucose-sugar-from the bloodstream into the body's cells where it can be used.
The researchers suppressed one of the key proteins in this pathway in honeybee larvae.
The protein, called the insulin receptor substrate (IRS), has been linked to growth, development and reproduction in mice.
The researchers fed the altered larvae a queen's diet, but they developed into workers, not queens.
IRS is only one component of the process that decides a bee's ultimate fate.
Wolschin says several other molecules are known to play a role, including DNA methyltransferase, juvenile hormone and a protein called TOR.
"Those are all very important and fundamental mechanisms. One single part cannot alone be responsible. It has to be the interplay between different mechanisms that finally results in the divergence of queens and workers," said Wolschin. (ANI)