In their study, the researchers took a close look at a species that has long been studied at the University of Bonn — the resurrection plant Craterostigma plantagineum. It bears its name quite rightly: In times of drought, one might think it is dead. But even after months of drought, a little water is enough to revive it. “At our institute, we have been studying how the plant does this for many years,” explains Prof. Dr. Dorothea Bartels from the Institute of Molecular Physiology and Biotechnology of Plants (IMBIO) at the University of Bonn.

Her interests include the genes that are responsible for drought tolerance. It became increasingly clear that this ability is not the result of a single “miracle gene.” Instead, a great many genes are involved, most of which are also found in species that do not cope so well with drought.

The plant has eight copies of each chromosome

In the current study, Bartel’s team, together with researchers from the University of Michigan (USA), analyzed the complete genome of Craterostigma plantagineum. And this is built quite complex: While most animals have two copies of each chromosome — one from the mother, one from the father — Craterostigma has eight. Such an “eightfold” genome is also called octoploid. We humans, in contrast, are diploid.

“Such a multiplication of genetic information can be observed in many plants that have evolved under extreme conditions,” Bartels says. But why is that? A probable reason: If a gene is present in eight copies instead of two, it can in principle be read four times as fast. An octoploid genome can therefore enable large quantities of a required protein to be produced very quickly. This ability also appears to be important for the development of drought tolerance.

In Craterostigma, some genes associated with greater tolerance to drought are even further replicated. These include the so-called ELIPs — the acronym stands for “early light inducible proteins,” as they are rapidly switched on by light and protect against oxidative stress. They occur in high copy numbers in all drought-tolerant species. “Craterostigma has close to 200-ELIP genes that are nearly identical and are located in large clusters of ten or twenty copies on different chromosomes,” Bartels explains. Drought-tolerant plants can therefore presumably draw on an extensive network of genes that they can rapidly upregulate in the event of drought.

Drought-sensitive species usually have the same genes — albeit in lower copy numbers. This is also not surprising: The seeds and pollen of most plants are often still able to germinate after long periods without water. So they also have a genetic program to protect against drought. “However, this program is normally switched off at germination and cannot be reactivated afterwards,” the botanist explains. “In resurrection plants, in contrast, it remains active.”

Most species “can do” drought tolerance

Drought tolerance, then, is something that the vast majority of plants “can do.” The genes that confer this ability probably emerged very early in the course of evolution. However, these networks are more efficient in drought-tolerant species and, moreover, are not active only at certain stages of the life cycle.

That said, not every cell in Craterostigma plantagineum has the same “drought program” either. This was shown by researchers from the University of Düsseldorf, who were also involved in the study. For instance, different drought network genes are active in roots during desiccation than in leaves. This finding is not unexpected: Leaves, for instance, need to protect themselves against the damaging effects of the sun. They are helped in this by ELIPs, for example. With sufficient moisture, the plant forms photosynthetic pigments that at least partially absorb radiation. This natural protection largely fails during drought. Roots, in contrast, do not have to worry about sunburn.

The study improves understanding of why some species suffer so little from drought. In the long term, it could therefore contribute to the breeding of crops such as wheat or corn that cope better with drought. In times of climate change, these are likely to be in greater demand than ever in the future.

Participating institutions and funding:

In addition to the University of Bonn, Michigan State University (USA) and Heinrich Heine University Düsseldorf were involved in the study. The work was funded by the US National Science Foundation (NSF) and the German Research Foundation (DFG).

Nitroxoline is the name of the new drug candidate that could potentially be used to treat mpox. It was identified by scientists at Goethe University and the University of Kent as part of a multi-site study. The results of their research will now allow clinical trials to begin soon.

The current mpox outbreak is the first of this size to occur outside of Africa and also the first mpox outbreak caused by human-to-human transmission. People with immunodeficiencies are particularly at risk from the disease. Although antiviral agents have already been shown to inhibit the replication of the mpox virus in experimental models, the efficacy of these substances has not yet been confirmed in humans and some may have significant side effects. In addition, there are insufficient stocks to treat all mpox patients. Moreover, resistance formation against tecovirimat, the most promising mpox drug candidate to date, has already been reported.

In the present study, the international team led by Professor Jindrich Cinatl (of Goethe University Frankfurt and the Dr. Petra Joh-Research Institute) and Professor Martin Michaelis (School of Biosciences, University of Kent) has identified nitroxoline, a well-tolerated antibiotic, as a potential treatment alternative for the mpox virus based on experiments using cell culture and skin explant models.

Nitroxoline is also effective against a tecovirimat-resistant strain of the mpox virus, as well as other bacterial and viral pathogens that are frequently co-transmitted with mpox viruses, meaning it simultaneously suppresses multiple pathogens that are often involved in severe courses of mpox. Since nitroxoline is a well-tolerated antibiotic that has long been used to treat humans, it can be tested directly against mpox in clinical trials.

“The emergence of resistant virus strains is a cause of great concern,” says Professor Jindrich Cinatl of Goethe University and the Dr. Petra Joh-Research Institute. “It is very reassuring that nitroxoline is effective against a tecovirimat-resistant virus.”

Professor Martin Michaelis of the University of Kent adds: “The more different drugs become available to treat viral diseases, the better. We hope that nitroxoline will turn out to be an effective treatment for mpox patients.”

Telomeres on chromosomes protect DNA from degrading, but every time a cell divides, the telomeres lose some of their length. Short telomeres are a sign of stress and cellular aging, and are also associated with a higher risk of neurological and psychiatric disorders. Currently, little is known about the links between telomere length and changes that occur in the brains of people with neurological conditions. Understanding those relationships could offer insights into the biological mechanisms that cause neurodegenerative disorders.

In the new study, researchers compared telomere length in white blood cells to results from brain MRIs and electronic health records from more than 31,000 participants in the UK Biobank, a large-scale biomedical database and research resource containing anonymized genetic, lifestyle and health information from half a million UK participants. The analysis revealed that patients with longer telomeres also tended to have better brain health. They had a larger volume of grey matter in their brains overall and a larger hippocampus, both of which shrink in patients with Alzheimer’s disease. Longer telomeres were also associated with a thicker cerebral cortex — the outer, folded layer of grey matter — which thins as Alzheimer’s disease progresses. The researchers speculate that longer telomeres might therefore help protect patients from developing dementia, though there was no association with stroke or Parkinson’s disease.

Overall, the findings show that shorter telomeres can be linked to multiple changes in the brain associated with dementia. To date, this is the largest and richest study of the relationships between telomere length and MRI markers in the brain. The associations suggest that accelerated aging in the brain, as indicated by telomere length, could represent a biological pathway that leads to neurodegenerative disease.

The authors add: “We found associations between telomere length, a marker of biological ageing, and multiple aspects of brain structure. This may explain why individuals with longer telomeres have a lower risk of dementia.”

Forever chemicals, formally known as PFAS (per-and polyfluoroalkyl substances) are a large group of substances that make certain products non-stick or stain-resistant. There are more than 4,700 PFAS in use, mostly in raingear, non-stick cookware, stain repellents and firefighting foam. Research links these chemicals to a wide range of health problems including hormonal disruption, cardiovascular disease, developmental delays and cancer.

To remove PFAS from drinking water, Dr. Mohseni and his team devised a unique adsorbing material that is capable of trapping and holding all the PFAS present in the water supply.

The PFAS are then destroyed using special electrochemical and photochemical techniques, also developed at the Mohseni lab and described in part in a new paper published recently in Chemosphere.

While there are treatments currently on the market, like activated carbon and ion-exchange systems which are widely used in homes and industry, they do not effectively capture all the different PFAS, or they require longer treatment time, Dr. Mohseni explained.

“Our adsorbing media captures up to 99 per cent of PFAS particles and can also be regenerated and potentially reused. This means that when we scrub off the PFAS from these materials, we do not end up with more highly toxic solid waste that will be another major environmental challenge.”

He explained that while PFAS are no longer manufactured in Canada, they are still incorporated in many consumer products and can then leach into the environment. For example, when we apply stain-resistant or repellent sprays/materials, wash PFAS-treated raingear, or use certain foams to put down fires, the chemicals end up in our waterways. Or when we use PFAS-containing cosmetics and sunscreens, the chemicals could find their way into the body.

For most people, exposure is through food and consumer products, but they can also be exposed from drinking water — particularly if they live in areas with contaminated water sources.

Dr. Mohseni, whose research group also focuses on developing water solutions for rural, remote and Indigenous communities, noted: “Our adsorbing media are particularly beneficial for people living in smaller communities who lack resources to implement the most advanced and expensive solutions that could capture PFAS. These can also be used in the form of decentralized and in-home water treatments.”

The UBC team is preparing to pilot the new technology at a number of locations in B.C. starting this month.

“The results we obtain from these real-world field studies will allow us to further optimize the technology and have it ready as products that municipalities, industry and individuals can use to eliminate PFAS in their water,” said Dr. Mohseni.