Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rapid evolution: New findings on its molecular mechanisms

14.08.2019

Evolutionary biologists from Konstanz analyze the role of microRNAs in the evolution of new species

The mechanisms by which new species arise are still not fully understood. What are the evolutionary processes that drive the evolution of new species? Evolutionary biologists traditionally assumed that geographical barriers between animal populations play a decisive role (allopatric speciation): a species is physically separated into two or more isolated populations, thereby preventing gene flow between these groups.


The Midas cichlid fish from the crater lakes of Nicaragua are one of the the best known examples for sympatric speciation. They evolved from a source population into a variety of independent species in less than 22,000 years.

University of Konstanz

The subpopulations adapt to their respective habitats and evolve into independent species with different characteristics. In recent years, however, the evolutionary biologist Professor Axel Meyer from the University of Konstanz has not only been able to show that new species can evolve from a source population within a shared habitat and in the presence of gene flow (sympatric speciation), but that this type of speciation might be much more common than previously thought.

His laboratory is investigating both the ecological and genetic mechanisms that facilitate sympatric speciation. In a recent publication in the scientific journal Molecular Biology and Evolution, Axel Meyer and his colleagues Paolo Franchini, Peiwen Xiong, Carmelo Fruciano, Ralf Schneider, Joost Woltering and Darrin Hulsey identify the decisive role that a kind of genetic switch, microRNAs, play in sympatric speciation.

Rapid evolution of cichlids

The researchers led by Axel Meyer analyze the Midas cichlid fish from Nicaragua's volcanic crater lakes as a model system in their research. Cichlids are known for their ability to adapt to new environments at an exceptionally rapid rate and to form new species.

The new fish species originate from a population found in the large lakes of Nicaragua, but after colonizing several very small and young crater lakes, they adapted to new ecological niches, evolved new characteristics (e.g. a more elongated body or a different jaw) and evolved into a variety of new species in less than 22,000 years.

A further distinctive feature of these Midas cichlids is that they evolved into different species within the same population, sometimes repeatedly, by adapting to different ecological niches within their small crater lakes. The Midas cichlids of Nicaragua are thus one of the best known examples for sympatric speciation.

Within such a short time period new mutations are very unlikely to happen. This made finding a molecular mechanism that can bring about different body shapes, adaptations and thereby distinct ecological niches so difficult and interesting. The evolution of microRNAs and new target sites for them to regulate the expression of genes offers one potential molecular mechanism that can bring about very fast evolutionary change with very little genetic differences between the extremely young species.

microRNA

The biologists from Konstanz carried out genetic analyses of five species of Midas cichlids from the crater lakes Apoyo and Xiloá. Here, they focused in particular on the function of the so-called microRNA – a non-coding ribonucleic acid that has a regulatory effect on gene expression. The researchers found an increased activity of microRNA in young fish one day after they hatched during a phase in which the fish bodies are formed.

They analyzed the interaction between microRNA and gene expression, identifying specific pairs of microRNAs and genes that influence each other. The microRNA suppresses the expression of the target genes and thus has a regulatory effect on them: the more active a particular microRNA is, the more effectively the target gene is suppressed or “switched off”. “Our research results provide strong evidence that extremely quickly evolving microRNA regulation contributes to the rapid sympatric speciation of Midas cichlids," says Paolo Franchini.

Facts:

- Evolutionary biologists from Konstanz investigate the role of microRNA in the rapid sympatric speciation of Midas cichlids – the evolution of new species within the same habitat and in the presence of gene flow.

- Original publication: Paolo Franchini, Peiwen Xiong, Carmelo Fruciano, Ralf F Schneider, Joost M Woltering, C Darrin Hulsey, Axel Meyer, MicroRNA gene regulation in extremely young and parallel adaptive radiations of crater lake cichlid fish, Molecular Biology and Evolution, msz168
Link: https://academic.oup.com/mbe/advance-article/doi/10.1093/molbev/msz168/5545549

- Genetic analyses of five species of Midas cichlids from the crater lakes Apoyo and Xiloá, which evolved out of a shared source population into new species in far less than 22,000 years.

- Analyses of the interaction between microRNA and genes. Specific pairs of microRNAs and genes that interact with each other were identified. The microRNA suppresses the expression of the target genes.

- This research project was carried out in the context of Professor Axel Meyer’s ERC Advanced Grant “Comparative genomics of parallel evolution in repeated adaptive radiations” (GenAdap 293700). The project was also funded by a German Research Foundation (DFG) grant (FR 3399/1-1).

Note to editors:
You can download pictures here:

https://cms.uni-konstanz.de/fileadmin/pi/fileserver/2019/Bilder/Evolution_1.jpg
Caption: The Midas cichlid fish from the crater lakes of Nicaragua are one of the the best known examples for sympatric speciation. They evolved from a source population into a variety of independent species in less than 22,000 years.

https://cms.uni-konstanz.de/fileadmin/pi/fileserver/2019/Bilder/Evolution.jpg
Caption: Researchers found an increased activity of microRNA in young fish one day after they hatched.

Wissenschaftliche Ansprechpartner:

Prof. Axel Meyer, Dr. Paolo Franchini
University of Konstanz

Originalpublikation:

Paolo Franchini, Peiwen Xiong, Carmelo Fruciano, Ralf F Schneider, Joost M Woltering, C Darrin Hulsey, Axel Meyer, MicroRNA gene regulation in extremely young and parallel adaptive radiations of crater lake cichlid fish, Molecular Biology and Evolution, msz168
Link: https://academic.oup.com/mbe/advance-article/doi/10.1093/molbev/msz168/5545549

Julia Wandt | idw - Informationsdienst Wissenschaft

More articles from Life Sciences:

nachricht Predicting a protein's behavior from its appearance
10.12.2019 | Ecole Polytechnique Fédérale de Lausanne

nachricht Could dark carbon be hiding the true scale of ocean 'dead zones'?
10.12.2019 | University of Plymouth

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: How to induce magnetism in graphene

Graphene, a two-dimensional structure made of carbon, is a material with excellent mechanical, electronic and optical properties. However, it did not seem suitable for magnetic applications. Together with international partners, Empa researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronic applications. The results have just been published in the renowned journal Nature Nanotechnology.

Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties – for example,...

Im Focus: Electronic map reveals 'rules of the road' in superconductor

Band structure map exposes iron selenide's enigmatic electronic signature

Using a clever technique that causes unruly crystals of iron selenide to snap into alignment, Rice University physicists have drawn a detailed map that reveals...

Im Focus: Developing a digital twin

University of Texas and MIT researchers create virtual UAVs that can predict vehicle health, enable autonomous decision-making

In the not too distant future, we can expect to see our skies filled with unmanned aerial vehicles (UAVs) delivering packages, maybe even people, from location...

Im Focus: The coldest reaction

With ultracold chemistry, researchers get a first look at exactly what happens during a chemical reaction

The coldest chemical reaction in the known universe took place in what appears to be a chaotic mess of lasers. The appearance deceives: Deep within that...

Im Focus: How do scars form? Fascia function as a repository of mobile scar tissue

Abnormal scarring is a serious threat resulting in non-healing chronic wounds or fibrosis. Scars form when fibroblasts, a type of cell of connective tissue, reach wounded skin and deposit plugs of extracellular matrix. Until today, the question about the exact anatomical origin of these fibroblasts has not been answered. In order to find potential ways of influencing the scarring process, the team of Dr. Yuval Rinkevich, Group Leader for Regenerative Biology at the Institute of Lung Biology and Disease at Helmholtz Zentrum München, aimed to finally find an answer. As it was already known that all scars derive from a fibroblast lineage expressing the Engrailed-1 gene - a lineage not only present in skin, but also in fascia - the researchers intentionally tried to understand whether or not fascia might be the origin of fibroblasts.

Fibroblasts kit - ready to heal wounds

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

The Future of Work

03.12.2019 | Event News

First International Conference on Agrophotovoltaics in August 2020

15.11.2019 | Event News

Laser Symposium on Electromobility in Aachen: trends for the mobility revolution

15.11.2019 | Event News

 
Latest News

City research draws on Formula 1 technology for the construction of skyscrapers

10.12.2019 | Architecture and Construction

Reorganizing a computer chip: Transistors can now both process and store information

10.12.2019 | Information Technology

Could dark carbon be hiding the true scale of ocean 'dead zones'?

10.12.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>