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
In focus: Peptides, the “little brothers and sisters” of proteins
12.11.2018 | Technische Universität Berlin
How to produce fluorescent nanoparticles for medical applications in a nuclear reactor
09.11.2018 | Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences (IOCB Prague)
Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.
In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...
On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.
When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure
Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...
Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly
The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...
Scientists developed specially coated nanometer-sized vehicles that can be actively moved through dense tissue like the vitreous of the eye. So far, the transport of nano-vehicles has only been demonstrated in model systems or biological fluids, but not in real tissue. The work was published in the journal Science Advances and constitutes one step further towards nanorobots becoming minimally-invasive tools for precisely delivering medicine to where it is needed.
Researchers of the “Micro, Nano and Molecular Systems” Lab at the Max Planck Institute for Intelligent Systems in Stuttgart, together with an international...
09.11.2018 | Event News
06.11.2018 | Event News
23.10.2018 | Event News
12.11.2018 | Life Sciences
12.11.2018 | Materials Sciences
12.11.2018 | Physics and Astronomy