Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

“Junk DNA“ May Give Rise to Evolutionary Innovation

02.11.2011
Heidelberg scientists have found that evolution can produce novelty from scratch

The vast majority of the human genome consists of DNA without any apparent function, so-called “junk DNA”. A study conducted by the scientists Dr. Laurence Ettwiller and Michael Eichenlaub at Heidelberg University's Centre for Organismal Studies now highlights this “dark matter” of the genome as a resource for evolutionary novelty.


The green fluorescent protein (GFP) labels in green the domains where the “de novo“ enhancers are active in the medaka fish (Oryzias latipes).
Image: Ettwiller / Eichenlaub


Japanese freshwater fish Medaka
Image: Ettwiller / Eichenlaub

The scientists found that even small changes in functionally inactive “junk DNA“ are sufficient to create essential control elements in gene regulation known as enhancers. The results of the study will be published on 1 November 2011 in “PLoS Biology”.

Genetic variation in humans is not primarily due to differences in the 1.5 percent of DNA that code for gene products. Rather, experts today assume that most differences between humans are the result of changes in those DNA sequences that control gene regulation, i.e. the formation of gene products such as proteins. Enhancers are an essential component in the control mechanism of gene regulation. Changes in enhancers can lead to disease and malformation; on the other hand, they carry the potential for evolutionary innovation.

Michael Eichenlaub and Laurence Ettwiller have shown that such innovation can occur through “de novo” formation of new enhancers, arising from slight changes in the DNA that had no regulatory activity before. This finding contrasts with the general view amongst evolutionary scientists that novelty mainly arises from modification of pre-existing functional components of the genome. This view has generally led scientists to focus their attention on the loss and modification of functional elements, neglecting variations in the “junk DNA“, which makes up about 97 percent of genetic information. “This work brings such neglected regions of the genome to the forefront as a putative ‘breeding ground‘ for new enhancers“, says Laurence Ettwiller, who headed the study.

To prove the existence of those new enhancers, the Heidelberg scientists designed an assay in the Japanese freshwater fish Medaka to capture rare events in which the sequence of a novel enhancer could be traced to other related species and validated these sequences experimentally. In several cases, they found evidence of a “de novo“ formation of new enhancers. “Even though this study has been conducted in fish, the same mechanisms apply to the human genome”, says Dr. Ettwiller.

“The study demonstrates that the slow but persistent changes that occur in DNA in each generation are sufficient to eventually lead to the apparition of new functions”, explains Michael Eichenlaub. “The methods we have established here could help to identify the changes that have contributed to the evolution of our species and explain the 1.23 percent of the genetic information that differ between the chimp’s and our genomes”, adds Dr. Ettwiller.

For more information, visit http://www.cos.uni-heidelberg.de/forschung/ettwiller/index.html.

Original publication:
Eichenlaub MP, Ettwiller L: De Novo Genesis of Enhancers in Vertebrates. PLoS Biol 9(11): e1001188. doi:10.1371/journal.pbio.1001188
Contact:
Dr. Laurence Ettwiller
Centre for Organismal Studies
Phone +49 6221 546495
laurence.ettwiller@cos.uni-heidelberg.de
Communications and Marketing
Press Office, phone +49 6221 542311
presse@rektorat.uni-heidelberg.de

Marietta Fuhrmann-Koch | idw
Further information:
http://www.uni-heidelberg.de
http://www.cos.uni-heidelberg.de/forschung/ettwiller/index.html

More articles from Life Sciences:

nachricht Elusive compounds of greenhouse gas isolated by Warwick chemists
18.09.2019 | University of Warwick

nachricht Study gives clues to the origin of Huntington's disease, and a new way to find drugs
18.09.2019 | Rockefeller 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: Happy hour for time-resolved crystallography

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Hamburg and the European Molecular Biology Laboratory (EMBL) outstation in the city have developed a new method to watch biomolecules at work. This method dramatically simplifies starting enzymatic reactions by mixing a cocktail of small amounts of liquids with protein crystals. Determination of the protein structures at different times after mixing can be assembled into a time-lapse sequence that shows the molecular foundations of biology.

The functions of biomolecules are determined by their motions and structural changes. Yet it is a formidable challenge to understand these dynamic motions.

Im Focus: Modular OLED light strips

At the International Symposium on Automotive Lighting 2019 (ISAL) in Darmstadt from September 23 to 25, 2019, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, a provider of research and development services in the field of organic electronics, will present OLED light strips of any length with additional functionalities for the first time at booth no. 37.

Almost everyone is familiar with light strips for interior design. LED strips are available by the metre in DIY stores around the corner and are just as often...

Im Focus: Tomorrow´s coolants of choice

Scientists assess the potential of magnetic-cooling materials

Later during this century, around 2060, a paradigm shift in global energy consumption is expected: we will spend more energy for cooling than for heating....

Im Focus: The working of a molecular string phone

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Potsdam (both in Germany) and the University of Toronto (Canada) have pieced together a detailed time-lapse movie revealing all the major steps during the catalytic cycle of an enzyme. Surprisingly, the communication between the protein units is accomplished via a water-network akin to a string telephone. This communication is aligned with a ‘breathing’ motion, that is the expansion and contraction of the protein.

This time-lapse sequence of structures reveals dynamic motions as a fundamental element in the molecular foundations of biology.

Im Focus: Milestones on the Way to the Nuclear Clock

Two research teams have succeeded simultaneously in measuring the long-sought Thorium nuclear transition, which enables extremely precise nuclear clocks. TU Wien (Vienna) is part of both teams.

If you want to build the most accurate clock in the world, you need something that "ticks" very fast and extremely precise. In an atomic clock, electrons are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

AI for Laser Technology Conference: optimizing the use of lasers with artificial intelligence

29.08.2019 | Event News

 
Latest News

Stroke patients relearning how to walk with peculiar shoe

18.09.2019 | Innovative Products

Statistical inference to mimic the operating manner of highly-experienced crystallographer

18.09.2019 | Physics and Astronomy

Scientists' design discovery doubles conductivity of indium oxide transparent coatings

18.09.2019 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>