Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Fruit fly sperm makes females do housework after sex

01.10.2009
The sperm of male fruit flies are coated with a chemical 'sex peptide' which inhibits the female's usual afternoon siesta and compels her into an intense period of foraging activity.

The surprise discovery was made by Professor Elwyn Isaac from the University of Leeds' Faculty of Biological Sciences when investigating the marked differences in sleeping patterns between virgin and mated females.

Both male and female fruit flies (Drosophila melanogaster) – commonly seen hovering around rotting fruit and vegetables - are active at dawn and dusk, and have a deep sleep at night. They also exhibit a marked 'resting state' during the afternoon, which Professor Isaac likens to a siesta that conserves the fly's energy and reduces damaging exposure to the sun during hot afternoons.

"However, we noted that after mating, females still slept deeply at night, but ditched the usual siesta in favour of extra foraging and searching for places to lay her eggs," he says. "This behaviour lasts for around eight days – and our research findings suggest that this change is not by choice. Females who mated with males that produced sperm without the sex peptide continued to take their siesta. So we're certain that this change of behaviour is chemically induced by the male."

"Sleep is an ancient and essential mechanism in living creatures from worms to humans, so to inhibit this for such a long period and replace it with extra activity that exposes the female to environmental hazards and danger from predators must require a powerful mechanism," he says.

The sex peptide is produced in the males' accessory glands (the equivalent of the human prostate gland) and attaches itself to the surface of the sperm's tail. Previous research studies have shown that the sex peptide encourages females to increase egg production - a mated female will lay up to 100 eggs a day compared with 1-2 eggs laid by a virgin female. It also inhibits her from mating with other males for around a week to ten days.

"It would appear that preventing sleep and inducing extra domestic-type duties to prepare for the birth of offspring in females is a further tactic used by the male to ensure successful paternity after mating," says Professor Isaac.

Professor Isaac says that the discovery sheds further light on the role of signalling molecules in the brain. "If we can work out exactly how this natural molecular switch can disrupt sleep behaviour, we may be able to apply this knowledge to neurological disorders relating to human sleep such as narcolepsy, which we think is caused by a fault in the neuropeptide signalling pathway in the brain."

Fruit flies are a good model for looking at sleep behaviour in humans as they exhibit many of the hallmarks of mammalian sleep. For example they sleep deeply at night from which they're difficult to rouse and they have a preferred sleeping posture. If kept awake through the night, they exhibit tiredness the next day; if fed caffeine, they stay awake, and they become drowsy if given antihistamines. The fruit fly's genome has also been fully mapped, so wide ranging genetic studies are possible.

Jo Kelly | EurekAlert!
Further information:
http://www.leeds.ac.uk

More articles from Life Sciences:

nachricht Scientists spin artificial silk from whey protein
24.01.2017 | Deutsches Elektronen-Synchrotron DESY

nachricht Choreographing the microRNA-target dance
24.01.2017 | UT Southwestern Medical Center

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists spin artificial silk from whey protein

X-ray study throws light on key process for production

A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Breaking the optical bandwidth record of stable pulsed lasers

24.01.2017 | Physics and Astronomy

Choreographing the microRNA-target dance

24.01.2017 | Life Sciences

Spanish scientists create a 3-D bioprinter to print human skin

24.01.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>