Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

MicroRNA: a glimpse into the past

01.02.2010
Small molecules give EMBL scientists bigger picture of animal evolution

The last ancestor we shared with worms, which roamed the seas around 600 million years ago, may already have had a sophisticated brain that released hormones into the blood and was connected to various sensory organs.

The evidence comes not from a newly found fossil but from the study of microRNAs – small RNA molecules that regulate gene expression – in animals alive today. Scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, have discovered that these molecules are found in the exact same tissues in animals as diverse as sea anemones, worms, and humans, hinting at an early origin of these tissues in animal evolution.

Their findings, published today in Nature, also open new avenues for studying the current functions of specific microRNAs.

Animals from different branches of the evolutionary tree – different lineages – possess specific microRNAs that evolved only in their lineage. But they also have microRNAs in common: ones which they inherited from their last common ancestor, and which have been conserved throughout animal evolution.

The EMBL scientists looked at the marine annelid Platynereis dumerilii, which is thought to have changed little over the past 600 million years. They visualised where these conserved microRNAs are expressed, and compared Platynereis with other animals. They found that in Platynereis these microRNAs are highly specific for certain tissues and cell types and, what is more, discovered that tissue specificity was conserved over hundreds of millions of years of evolutionary time.

The scientists reasoned that if an ancient microRNA is found in a specific part of the brain in one species and in a very similar location in another species, then this brain part probably already existed in the last common ancestor of those species. Thus, they were able to glean a glimpse of the past, an idea of some of the traits of the last common ancestor of worms and humans.

“By looking at where in the body different microRNAs evolved, we can build a picture of ancestors for which we have no fossils, and uncover traits that fossils simply cannot show us,” says Detlev Arendt, who headed the study: “But uncovering where these ancient microRNAs are expressed in animals from different branches of the evolutionary tree has so far been very challenging.”

“We found that annelids such as Platynereis and vertebrates such as ourselves share some microRNAs that are specific to the parts of the central nervous system that secrete hormones into the blood, and others that are restricted to other parts of the central or peripheral nervous systems, or to gut or musculature”, explains Foteini Christodoulou, who carried out most of the experimental work. “This means that our last common ancestor already had all these structures.”

Knowing where microRNAs were expressed in our ancestors could also help scientists understand the role of specific microRNA molecules today, as it gives them a clue of where to look.

“If a certain microRNA is known to have evolved in the gut, for instance, it is likely to still carry out a function there”, explains EMBL scientist Peer Bork, who also contributed to the study.

Next, Arendt and colleagues would like to investigate the exact function of each of these conserved microRNAs – what genes they regulated, and what processes those genes were involved in – in an attempt to determine what their role might have been in the ancient past.

Sonia Furtado
EMBL Press Officer
Meyerhofstr. 1, 69117 Heidelberg, Germany
Tel.: +49 (0)6221 387 8263
Fax: +49 (0)6221 387 8525
sonia.furtado@embl.de

Sonia Furtado | EMBL
Further information:
http://www.embl.org

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

DGIST develops 20 times faster biosensor

24.04.2017 | Physics and Astronomy

Nanoimprinted hyperlens array: Paving the way for practical super-resolution imaging

24.04.2017 | Materials Sciences

Atomic-level motion may drive bacteria's ability to evade immune system defenses

24.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>