Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

How insects decide to grow up

27.01.2017

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.


Image of a maggot (left); the steroid producing cells with the maggot brain (middle); and an expanded image of the steroid producing cells (right). Note large nuclei (dense white area) of steroid producing cells, which are labeled with a green fluorescent marker.

Credit: UC Riverside

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.

"The amount of DNA is like an internal timer for insect development," Yamanaka said. "It tells the insect, 'OK, I will grow up now.'"

Their finding explains, for the first time, why insect metamorphosis, just like human puberty, is an irreversible process. It is irreversible since DNA duplication cannot be reversed in cells. Once the cells increase the amount of DNA and start producing steroid hormones, that is the point of no return; they cannot go back to their childhood.

The findings could have multiple applications. In the short term, they could be used to help control agricultural pests by manipulating their steroid signaling pathways. They could also be used to aid beneficial insects, such as bees.

In the long term, the findings could also be used to develop better ways to treat diseases in humans related to sexual maturation, since human puberty is also controlled by steroid hormones, just like insects. The results may also aide future studies on steroid-related diseases such as breast cancer, prostate cancer, and menopause-related symptoms.

Yamanaka will continue this research by focusing on other insects, such as bumblebees and mosquitos, to see if they have a similar internal timer.

###

The PLOS Genetics paper is called "Nutrient-Dependent Endocycling in Steroidogenic Tissue Dictates Timing of Metamorphosis in Drosophila melanogaster."

In addition to Yamanaka, the co-authors are Yuya Ohhara, of the University of Shizuoka in Japan, who formerly worked in Yamanaka's lab at UC Riverside, and Satoru Kobayashi, of the University of Tsukuba in Japan.

Media Contact

Sean Nealon
sean.nealon@ucr.edu
951-827-1287

 @UCRiverside

http://www.ucr.edu 

Sean Nealon | EurekAlert!

More articles from Life Sciences:

nachricht How the gut ‘talks’ to brown fat
15.11.2018 |

nachricht Nanotubes built from protein crystals: Breakthrough in biomolecular engineering
15.11.2018 | Tokyo Institute of Technology

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland

15.11.2018 | Earth Sciences

When electric fields make spins swirl

15.11.2018 | Physics and Astronomy

Discovery of a cool super-Earth

15.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>