How Insects Decide to Grow Up

Typography

Scientists discover key mechanism that controls when fruit flies sexually mature

Like humans, insects go through puberty. The process is known as metamorphosis. Examples include caterpillars turning into butterflies and maggots turning into flies.

But, it has been a long-standing mystery as to what internal mechanisms control how insects go through metamorphosis and why it is irreversible.

Scientists discover key mechanism that controls when fruit flies sexually mature

Like humans, insects go through puberty. The process is known as metamorphosis. Examples include caterpillars turning into butterflies and maggots turning into flies.

But, it has been a long-standing mystery as to what internal mechanisms control how insects go through metamorphosis and why it is irreversible.

Now, a team of scientists, led by an assistant professor at the University of California, Riverside, has solved the mystery. They also believe the findings, which were just published in an early version in the journal PLOS Genetics, could be applied to mammals, including humans. The final version of the paper will be published Feb. 8.

Using the model organism fruit flies, the researchers found that the amount of DNA in the fruit fly controls the initial production of steroid hormones, which signal the start of metamorphosis.

More specifically, the cells that produce steroid hormones keep duplicating their DNA without cell division, making their nuclei huge. The team found that this amount of DNA in steroid hormone-producing cells is a critical indicator of their juvenile development, and it even determines when the insects get into metamorphosis.

Naoki Yamanaka, an assistant professor of entomology at UC Riverside, likened the accumulation of DNA to rings found inside trees that are used to date trees.

Read more at University of California, Riverside

Photo credit: UC Riverside