Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Aphids evolved special, surprising talents

30.04.2010
These insect pests pioneered new frontiers in genetics

Contrary to popular belief, aphids are not just sap-sucking, plant-destroying enemies of agriculture. In fact, these pests are genetic pioneers that evolved two unique traits, according to a study that appears in the April 30 issue of the journal Science.

First, aphids are, so far, the only animal known to produce essential pigments known as carotenoids. The aphid's pigment-producing ability is unique to the animal kingdom. Other animals, including humans, that need carotenoids cannot produce these essentials themselves; instead, they must obtain carotenoids from food.

Why are carotenoids needed by many plants and animals? Because they provide vital support to varied functions, ranging from promoting immunity to reducing cell damage and providing color to fruits and vegetables. For example, carotenoids give tomatoes their red color and flamingoes their pink color. Carotenoids also determine whether aphids are red or green--a color distinction that influences their vulnerabiilty to predators and other threats.

As for the second unique trait, aphids probably acquired their carotenoid-producing ability through a rare, and perhaps unique, process: millions of years ago, aphids apparently "snatched" carotenoid-producing genes from a carotenoid-producing member of the fungi kingdom, and then snapped those snatched genes into their own genetic code.

Gene transfer between organisms is not itself a rare phenomenon. However, the fungi-to-aphid gene transfer is the only known gene transfer between members of the fungi kingdom and animal kingdom--which are so evolutionarily distant from one another that it was long thought that never the twain would genetically meet.

But by busting through kingdom barriers, aphids gained something akin to a "genetic magic wand" that empowered them to produce their own carotenoids. They were thereby freed of the need to scavenge for carotenoid-yielding foods. The result: one less chore on the aphid's "to do" list, and a new self-sufficiency for these insects.

No one knows what compelled genes to jump from fungi to aphids. But "the transferred fungi genes may have originated from a closely associated fungus, such as one of the fungi that causes diseases in aphids," says Nancy Moran of the University of Arizona, the lead author of the Science paper. "Because the carotenoid-producing genes were the only fungus-related genes that we found in the aphid genes, we think that the fungi-to-aphid transfer was an extremely rare event."

"This is a very big discovery," says Matt Kane of the National Science Foundation. "By recognizing the horizontal transfer of nutritionally important carotenoid genes, Nancy Moran and her colleagues are the first to discover that gene transfer can occur between very distantly related groups of higher, multi-cellular organisms such as fungi and insects."

The foundation for the discovery of the fungi-to-aphid gene transfer was laid when a research team that included Moran constructed the first map of the entire genetic code of aphids. Then, when follow-up studies of the aphid's genetic map were conducted by a different research led by Moran, the presence of carotenoid-producing genes was discovered.

Because a few cases of bacterium-to-animal gene transfer are known and because aphids have close associations with bacterial symbionts, bacteria were initially considered a more likely suspect for genetic swapping with aphids than were the more genetically complex fungi. But after identifying signature similarities between the sequences and arrangements of the aphid and fungi carotenoid-producing genes, Moran's team was able to eliminate bacteria, as well as laboratory contamination, as potential sources for the aphids' carotenoid-producing genes.

Lily Whiteman | EurekAlert!
Further information:
http://www.nsf.gov

More articles from Life Sciences:

nachricht Separating methane and CO2 will become more efficient
18.10.2017 | KU Leuven

nachricht Bolstering fat cells offers potential new leukemia treatment
17.10.2017 | McMaster University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Researchers release the brakes on the immune system

18.10.2017 | Health and Medicine

Separating methane and CO2 will become more efficient

18.10.2017 | Life Sciences

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>