News 2020

Congratulations to Shrey Gandhi, who successfully defended his PhD today! Shrey conducted his PhD studies in the Department of Genetic Epidemiology at the Institute of Human Genetics supervised by Prof Monika Stoll. In his PhD project, he investigated the evolutionary mechanisms responsible for long non-coding RNA conservation in the heart and their role in cardiovascular development and disease across vertebrates.
Shrey was awarded one of two EvoPAD postdoc start-up grants and will stay at WWU and with EvoPAD until July 2021.
 

The Match-Mismatch hypothesis predicts that animals which have adapted to certain environmental conditions during early life may experience negative consequences for health and welfare if conditions change later in life, creating a mismatch between the expected and the actual environment. EvoPAD researchers at the Department of Behavioural Biology have now tested this hypothesis in laboratory mice in relation to food availability. They exposed mice to either matching or non-matching conditions of low and high food availability during adolescence and adulthood and subsequently analysed physiological and behavioural parameters to test effects on the mice's health and welfare. While physiological parameters concerning body weight and organ weights as well as stress hormone levels changed depending on the food availability, there were no indications for a mismatch effect on health and welfare. However, mice were able to quickly adjust to changes in food availability which possibly reflects their ecology: mice are exposed to quickly varying food availability in nature and any permanent change of phenotype would almost certainly represent a maladaptation later in life. Only a few behavioural parameters changed in reponse to food availabilty. Low food availability in general caused lower levels of anxiety-like behaviour which may represent an adequate reaction towards scarce environmental conditions in nature that force the animal to explore its environment and search for food. The study will be published in the January issue of Physiology & Behavior and is already available online.

Original article: Feige-Diller J, Palme R, Kaiser S, Sachser N, Richter SH (2020) The impact of varying food availability on health and welfare in mice: Testing the Match-Mismatch hypothesis. Physiology & Behavior 228:113193. 10.1016/j.physbeh.2020.113193 [doi]

In light of the ever-growing amount of available genomic data and the need for accessible and easily applicable tools to analyse these data by the broad scientific community, EvoPAD researchers Fengjun Zhang and Jürgen Schmitz together with their colleagues from the Institute of Experimental Pathology have developed the 2-n-way software. As an improvement to its precursor GPAC, 2-n-way allows for multidirectional comparisons with different reference genomes to screen for presence or absence of targeted elements. The results are presented in a user-friendly interactive table. The tool is available freely on the Institute's webpage and can be used independently of expensive computational equipment or bioinformatics expertise. The tool, together with application examples spanning genome architecture, functional genomics, population genomics, and phylogenomics has recently been published in Genome Research.

Original article: Churakov G*, Zhang F*, Grundmann N, Makalowski W, Noll A, Doronina L, Schmitz J (2020) The multi-comparative 2-n-way genome suite. Genome Research gr.262261.120 [online ahead of print]. doi: 10.1101/gr.262261.120 *equally contributing authors

Link to the 2-n-way tool

Press release by the WWU [in German]
 

As the current Covid-19 pandemic shows, infectious diseases spreading from animals to humans, so-called zoonoses, can be a major challenge on a global scale. In a recent episode of the WWU podcast, EvoPAD PI and zoonoses expert Stephan Ludwig talks about this development and what measures have to be taken by politics, econmonics and the population to prevent future outbreaks.
Listen to the full podcast (in German) here.

For a recent episode of the WWU podcast, EvoPAD PI Helene Richter was interviewed by WWU press officer Norbert Robers about her research. In the interview, Helene explains how animal welfare is studied, which factors enhance reproducibility in animal experiments, and how strict the legal situation in Germany is compared to other European countries.
Listen to the full podcast (in German) here.
 

Congratulations to Valerio Vitali who was awarded with his doctoral degree today! Valerio conducted his PhD studies in the Evolutionary Cell Biology Group at the Institute for Evolution and Biodiversity supervised by Dr Francesco Catania. In his PhD project, he investigated the impact of plasticity, environmental induction, and neutral molecular processes of germline-soma differentiation in organismal evolution using the ciliate Paramecium tetraurelia.
Valerio was awarded one of two EvoPAD postdoc start-up grants and will stay at WWU and with EvoPAD until December 2020.
 

EvoPAD welcomes 10 doctoral students that started their doctoral projects within the RTG between April and July 2020: Imke Temme (A2), Marla Keizers (A3), Rexford Dumevi (A2/A3), Moritz Baur (A4), Katrin Berk (B1), Raphael Steffen (B3), Amer Ghalawinji (B4), Elena Groneberg (B5), Marlene Sroka (B6), and Jonas Pöld (C2).
Together with the new cohort, three PhD students joined EvoPAD as associated students: Abdulbaki Çoban (Institute for Evolution and Biodiversity), Sriram Kumar (Institute of Molecular Virology), and Weizhao Sun (Institute for Evolution and Biodiversity).

A warm welcome to all our new members! 

Congratulations to Leonie Chiara Martens and Noble Selasi Gati who were awarded with their doctoral degrees today and are the first graduates within EvoPAD!
Leonie conducted her PhD studies in the Department of Genetic Epidemiology at the Institute of Human Genetics supervised by Prof Monika Stoll. In her PhD project, she identified novel genetic variants altering RNA secondary structure, called RiboSNitches, in complex cardiovascular disease. 
Selasi did his PhD studies at the Institute of Hygiene in the group of Prof Alexander Mellmann. In his PhD, he investigated the origin and evolution of heteropathogenic Escherichia coli.  We wish Leonie and Selasi all the best for their future careers!

The vast majority of eukaryotes reproduces sexually, yet, the evolution and maintenance of sexual reproduction remains a puzzle in evolutionary biology. Reproducing sexually comes with high costs: Each sexually reproducing organism can only produce half as many offspring as an asexually reproducing organism (since only the females bear offspring and they usually make up only 50% of the population). In addition, finding a mate requires energy and may increase predation risk. To balance these costs, sexual reproduction must have benefits. One such benefit may be genetic diversity generated by reshuffling of maternal and paternal alleles. However, many organisms perform self-fertilization, meaning they undergo sexual reproduction without a partner involved and thus without generating new genetic variation. Another, so far rather neglected hypothesis is that the molecular mechanisms underlying sexual reproduction overlap with those of the cellular stress-response thereby providing a direct fitness advantage to the individual when engaging in sexual reproduction under stressful conditions. Together with colleagues from the National Research Council in Naples, Italy, EvoPAD researchers Valerio Vitali and Francesco Catania tested this hypothesis in the ciliate Paramecium tetraurelia and published the results in the May issue of Genome Biology and Evolution, which also contains a Highlight profile of their manuscript. Their results show that self-fertilizing Paramecium cells are much more likely to survive after a heat-shock compared to genetically identical cells that divide asexually. Results from transcriptional data suggest that heat-shock proteins may play a role in meiosis/fertilization and the response to environmental stress at the same time. They also reveal connections between metabolism and developmental program, which are reminiscent of observations in multicellular organisms. These results indicate that sexually reproducing organisms may gain direct fitness benefits through an overlap in the molecular processes involved in sexual reproduction and stress response thereby contributing to the prevalence of sex.

The article has been featured on a number of science news platforms such as EurekAlert!, Phys.org, The Medical News, Technology Networks, and Quanta Magazine. Additionally, it will be featured in the German science podcast ‘Undoder zum Quadrat’.

Original article: Thind AS*, Vitali V*, Guarracino MR, Catania F (2020) What's genetic variation got to do with it? Starvation-induced self-fertilization enhances survival in Paramecium. Genome Biol Evol 12:626-638. 10.1093/gbe/evaa052 [doi]  *equally contributing authors

Highlight profile: McGrath C (2020) Highlight: Sex As Stress Management in Microbes. Genome Biol Evol 12:639-640. 10.1093/gbe/evaa0808 [doi]
 

EvoPAD PI Dr Francesco Catania is featured in a recent article discussing new insights into the evolution of sexual reproduction in Quanta magazine. Quanta magazine is an online publication aiming to enhance public understanding of science by reporting developments in mathematics, theoretical physics, theoretical computer science and the basic life sciences in an accessible manner to a broad audience. In the article, Francesco and others argue that while sexual reproduction usually carries costs to individuals and is thought to mainly benefit future generations through increasing genetic diversity, it may also directly benefit the individual engaging in sexual reproduction - especially in stressful environments. The basis for the article is a recent study headed by Francesco and EvoPAD PhD student Valerio Vitali published in Genome Biology and Evolution showing that self-fertilization can enhance stress resistance to starvation in the ciliate Paramecium tetraurelia.

Quanta magazine article: Why Sex? Biologists Find New Explanations, 23 April 2020

Original article: Thind AS*, Vitali V*, Guarracino MR, Catania F (2020) What’s genetic variation got to do with it? Starvation-induced self-fertilization enhances survival in Paramecium. Genome Biology and Evolution evaa052 doi: 10.1093/gbe/evaa052 *equally contributing authors
 

Bacteria of the species Bacillus thuringiensis are the most commonly used bioinsecticide. Those bacteria produce toxins that are activated upon ingestion in the insects’ gut and can lead, in some species, to midgut disruption leading to death by septicaemia. In a newly published study in Insects journal, EvoPAD researchers Ana Sofia Lindeza and Joachim Kurtz and colleague Caroline Zanchi adapted a non-invasive assay to study gut leakage, the Smurf assay, to two species of Tenebrionid beetles, the mealworm beetle Tenebrio molitor and the red flour beetle Tribolium castaneum. The Smurf assay uses a blue food dye that does not cross the healthy intestinal barrier but leaks into the hemocoel upon disruption of the intestinal barrier, giving the animals the characteristic blue stain after which it is named. The researchers used the assay to investigate the variability of hosts in the susceptibility to gut leakage and compared mortality and gut leakage induced by two different B. thuringiensis strains using as host systems. Results from their experiments show that younger and smaller larvae of T. molitor suffer higher mortality and die faster upon exposure to B. thuringiensis var. tenebrionis. However, this higher mortality was not accompanied by a higher incidence of gut leakage in small larvae as shown in the Smurf assay. In T. castaneum, they used the Smurf assay to compare exposure of larvae to the two B. thuringiensis strains var. tenebrionis and var. tolworthi. Larvae exposed to B. thuringiensis tenebrionis died faster and had a higher mortality 7 days after exposure. However, according to the Smurf assay there was no difference in the leakiness of the gut after exposure to the different strains. Interestingly, in both host systems, the occurrence of a Smurf phenotype indicating gut disruption was very low (less than 10%). These results could indicate that contrary to prior expectations, extensive gut leakage is not a widespread killing mechanism of B. thuringiensis in T. molitor and T. castaneum. Alternative mechanism to gut’s leakage may include toxemia or starvation due to arrested feeding.

Original article: Zanchi C*, Lindeza AS*, Kurtz J (2020) Comparative mortality and Adaptation of a Smurf Assay in Two Species of Tenebrionid Beetles Exposed to Bacillus thuringiensis. Insects 11:261. doi: 10.3390/insects11040261 *indicate equally contributing authors
 

This year's visit by EvoPAD Mercator Fellow Thomas Flatt had to be cancelled due to the measures to stem the spread of SARS-CoV-2. It is planned that he will visit EvoPAD again in 2021.

Animals in their natural habitats have to spend a large proportion of their time and energy to forage for food of varying nutritional values in many different places. Complex mechanisms have evolved to optimize this foraging behavior and maximize the achieved energy intake. If, however, food is readily available in abundance, these mechanisms are no longer adaptive and can cause severe health impairments. In a laboratory setting, for example, mice are given unrestricted access to high-energy food around the clock, which, correspondingly, has been linked to obesity and comorbidities. In contrast, reducing the animals’ body weight by feeding them less food once per day has been shown to enhance life span and reduce the vulnerability to disease.
Against this background, a new study by EvoPAD researchers Janina Feige-Diller, Sylvia Kaiser, Norbert Sachser, S. Helene Richter and colleagues published in Frontiers in Veterinary Science compared the effects of different feeding routines on the quality of life of laboratory mice. The results show that removing the food for 4 h per day did not lead to a reduction of body weight, and hence is unlikely to prevent negative effects of overfeeding. In contrast, feeding less food once per day or automatically supplying less food as small pieces all over the day led to the aspired body weight reduction. For the latter feeding routine, however, behavioral and physiological changes were found which implied a rather negative impact on welfare. By contrast, no distinct negative effects were found for feeding a reduced amount of food once per day.

Original article: Feige-Diller J, Krakenberg V, Bierbaum L, Seifert L, Palme R, Kaiser S, Sachser N, Richter SH (2020) The Effects of Different Feeding Routines on Welfare in Laboratory Mice. Frontiers in Veterinary Science 6 (479). doi: 10.3389/fvets.2019.00479