Jumping genes, so-called transposons, reproduce as parasites in the genome. This selfish behaviour can be an evolutionary advantage for the organism or harm it. There is still a debate about the factors controlling the activity of transposons. Comparisons between populations could shed an answer on this but have been biased due to technical problems. The software PoPoolationTE2 developed by the Institute of Population Genetics at Vetmeduni Vienna enables an unbiased analysis for the first time and determines the frequency of transposons. This might also be useful for cancer research and neurology. The software was presented in the renowned journals Molecular Biology and Evolution.
The genome is not a fixed code but flexible. It allows changes in the genes. Transposons, however, so-called jumping genes, interpret this flexibility in a much freer way than “normal” genes. They reproduce in the genome and chose their position themselves. Transposons can also jump into a gene and render it inoperative. Thus, they are an important distinguishing mark for the development of different organisms.
Unclear what triggers transposon activity
However, it is still unclear how jumping genes developed and what influences their activity. “In order to find out how, for instance, climate zones influence activity, we must be able to compare the frequency of transposons in different populations – in different groups of individuals,” explained bioinformatician Robert Kofler from the Institute of Population Genetics at the University of Veterinary Medicine, Vienna. But this frequency has not yet been determined precisely.
New software for a low-priced method
Transposons are detected by DNA sequencing. But this detection cannot be carried out for every single member of a population. “At the moment, this would go beyond the available resources regarding finance and amount of work. The only – and much cheaper – option is to analyse an entire population in one reaction,” explained last author Christian Schlötterer. This method, which he has established using the example of fruit flies, is called Pool-Seq. It is also routinely applied to detect transposons.
Existing analysis programmes, however, could not provide a precise result in this case. So far, each analysis has been biased by different factors such as the sequencing depth and the distance between paired reads.
For this purpose, Kofler developed the new software PoPoolationTE2. “If we sequence entire populations, each reaction provides a different result. The number of mixed individuals is always the same, but the single individuals differ,” explained Kofler. Furthermore, technical differences in the sample processing, among others, have influenced the analysis so far. PoPoolationTE2 is not affected by these factors. Thus, questions about the activity of transposons can be answered precisely for Pool-Seq reactions.
Interesting for cancer research
“The unbiased detection of transposon abundance enables a low-price comparison of populations from, for instance, different climate zones. In a next step, we can find out if a transposon is very active in a particular climate zone,” said Kofler. In principle, the bioinformatician has developed this new software for Pool-Seq. But as this method is also applied in medical research and diagnosis, the programme is also interesting for cancer research or the detection of neurological changes since transposons also occur in the brain.
Lab experiments confirm influencing factors
Lab experiments can indicate the factors influencing transposons. Last author Schlötterer explained these factors referring to an experiment with fruit flies: “We breed a hundred generations per population and expose them to different stimuli. We sequence at every tenth generation and determine if a stimulus has influenced the activity of the transposons. Thus, we can describe the activity of transposons in fast motion, so to say.” If the abundance is low, the scientists assume that the transposons are only starting to become more frequent. If a transposon reproduces very quickly in a particular population, this is called an invasion. If a jumping gene is detected in an entire population and not in another one, it could have been positively selected.
The article “PoPoolationTE2: comparative population genomics of transposable elements using Pool-Seq“ by Robert Kofler, Daniel Gómez-Sánchez and Christian Schlötterer was published in the journal Molecular Biology and Evolution.
About the University of Veterinary Medicine, Vienna
The University of Veterinary Medicine, Vienna in Austria is one of the leading academic and research institutions in the field of Veterinary Sciences in Europe. About 1,300 employees and 2,300 students work on the campus in the north of Vienna which also houses five university clinics and various research sites. Outside of Vienna the university operates Teaching and Research Farms. http://www.vetmeduni.ac.at
Institute of Population Genetics
University of Veterinary Medicine Vienna (Vetmeduni Vienna)
T +43 1 25077-4333
Science Communication / Corporate Communications
University of Veterinary Medicine Vienna (Vetmeduni Vienna)
T +43 1 25077-1165
Mag.rer.nat. Georg Mair | Veterinärmedizinische Universität Wien
Researchers identify potentially druggable mutant p53 proteins that promote cancer growth
09.12.2016 | Cold Spring Harbor Laboratory
Plant-based substance boosts eyelash growth
09.12.2016 | Fraunhofer-Institut für Angewandte Polymerforschung IAP
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine