Big gaps in quest to sequence genomes of all animals

Efforts to sequence the genomes of the world’s animals tend to focus on those that most resemble humans with the work conducted almost entirely in the Global North, according to an analysis led by Washington State University.

In a paper published in the Proceedings of the National Academies of Sciences, researchers from WSU and Brigham Young University warn that current efforts are overlooking huge swathes of diversity and opportunity.

The analysis found that nearly 3,300 animal species have had their genomes sequenced and assembled, a process that gives organizational context to an organism’s DNA. While the rate is picking up, the number is small in comparison to the world’s 1.66 million animal species, and vertebrates make up the lion’s share of current sequences. They account for 54% of all the assemblies, despite representing only 3.9% of animal species. In contrast, the invertebrates of the Arthropoda phylum, which includes insects and spiders, comprise only 34% of current datasets while representing 78.5% of all species.

“With genome assemblies accumulating rapidly, we want to think about where we are putting our efforts. It’s not being spread evenly across the animal tree of life,” said lead author Scott Hotaling, a WSU post-doctoral researcher. “Invertebrates are still very underrepresented, which makes sense given that people seem to care more about vertebrates, the so-called ‘charismatic megafauna.'”

The family Hominidae, which includes great apes and humans, had the most contiguous genome data assembled, but the human genome is not the longest: that title goes to the Australian lungfish. Of all the genomic data, only five arthropod groups were well represented: bees, butterflies, mosquitoes, fruit flies and ants — all notable for the utility, or problems, they pose to humans.

“We are interested in ourselves, and that’s not necessarily a bad thing,” said Paul Frandsen, a corresponding author on the paper and a BYU assistant professor. “But to begin to understand entire ecosystems, we have to start sampling more of the variety of life to gain a clearer picture. Vertebrates are important components of ecosystems, but arguably insects and many other small creatures probably play an even more important role because they’re down at the base of the food web.”

The authors, Hotaling, Frandsen and WSU associate professor Joanna Kelley, also noted that the vast majority of genetic sequencing work is happening in developed countries often called the Global North because most are located in the Northern Hemisphere. Three countries, the United States, China and Switzerland produce the most. There were even certain proclivities for different regions with North America doing the most sequencing of mammals and insects, Europe of fish and Asia of birds.

In recent years, several large genome sequencing efforts have been announced, including the Earth BioGenome Initiative, which set an ambitious goal to sequence all of eukaryotic life, which includes animals, bacteria and one-celled organisms, within the next 10 years.

The current number of about 3,300 animal genome assemblies as of June 2021 is a big jump in 25 years from when the first animal genome sequence was produced, the Caenorhabditis elegans roundworm in 1998. But the authors calculated that at the current rate of about four genome assemblies per day, the goal of sequencing all eukaryotic life would not be reached until the year 3130.

The researchers propose that one way to help spur more work in this area would be to develop infrastructure and involve more researchers from countries in the Global South, particularly in tropical regions where there also happens to be a lot of animal diversity.

“If we want to build a global discipline, we need to include a global people,” Hotaling said. “It’s just basic equity, and from a pure scientific standpoint, the people who live in areas where species are being sequenced have a lot of knowledge about those species and ecosystems. They have a lot to contribute.”

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X-ray laser reveals how radiation damage arises

An international research team has used the X-ray laser European XFEL to gain new insights into how radiation damage occurs in biological tissue. The study reveals in detail how water molecules are broken apart by high-energy radiation, creating potentially hazardous radicals and electrically charged ions, which can go on to trigger harmful reactions in the organism. The team led by Maria Novella Piancastelli and Renaud Guillemin from the Sorbonne in Paris, Ludger Inhester from DESY and Till Jahnke from European XFEL is presenting its observations and analyses in the scientific journal Physical Review X.

Since water is present in every known living organism, the splitting of the water molecule H2O by radiation, called the photolysis of water, is often the starting point for radiation damage. “However, the chain of reactions that can be triggered in the body by high-energy radiation is still not fully understood,” explains Inhester. “For example, even just observing the formation of individual charged ions and reactive radicals in water when high-energy radiation is absorbed is already very difficult.”

To study this sequence of events, the researchers shot the intense pulses from the X-ray laser at the water vapour. Water molecules normally disintegrate on absorbing a single such high-energy X-ray photon. “Due to the particularly intense pulses from the X-ray laser, it was even possible to observe water molecules absorbing not just one, but two or even more X-ray photons before their debris flew apart,” Inhester reports. This gives the researchers a glimpse of what goes on inside the molecule after the first absorption of an X-ray photon.

“The movement of the molecule between two absorption events leaves a clear fingerprint, in other words, its fragments fly apart in a very specific, characteristic way,” says Piancastelli. “By carefully analysing this fingerprint, as well as using detailed simulations, we were able to draw conclusions about the ultra-fast dynamics of the water molecule after it had absorbed the first X-ray photon.” The team measured the directions in which the fragments travelled and their speeds using a so-called reaction microscope. This allowed the scientists to record the disintegration of the water molecule, which lasted only a few femtoseconds (quadrillionths of a second), in a kind of slow-motion movie.

It turns out that the disintegration of the water molecule is much more complicated than initially expected. The water molecule (H2O) starts to stretch and expand before eventually breaking apart. After only ten femtoseconds, the two hydrogen atoms (H), which are normally attached to the oxygen atom (O) at an angle of 104 degrees, can build up so much momentum as to face each other at an angle of around 180 degrees. As a result, the oxygen atom is not in fact flung away hard when the molecule breaks up, because the momenta of the two hydrogen nuclei largely balance each other out as they fly off, leaving the oxygen virtually at rest in the middle. In an aqueous environment, this free oxygen radical can then easily lead to further potentially harmful chemical reactions.

“In our research, we succeeded for the first time in taking a closer look at the dynamics of a water molecule after it absorbs high-energy radiation,” says Inhester, who works at the Centre for Free-Electron Laser Science (CFEL), a collaboration between DESY, the University of Hamburg and the Max Planck Society. “In particular, we were able to characterise the formation of the oxygen radical and the hydrogen ions more precisely, as well as the way this process unfolds over time. This disintegration of the water molecule is an important first step in the further chain of reactions that ultimately lead to radiation damage.”

The analysis adds to the overall picture of radiation effects on water. A previous study involving some members of the same team had explored the detailed dynamics of the formation of so-called free radicals by less energetic radiation in water. The processes observed there have similar dynamics to the secondary processes in the absorption of high-energy radiation now under investigation. The newly gained insights address elementary questions about reaction dynamics in water, which are to be further investigated at the Centre for Molecular Water Science (CMWS) currently being set up with international partners at DESY.

The new experiments on single water molecules were among the first performed with the new COLTRIMS reaction microscope at the experimental station SQS of the European XFEL. “The results show that we will be also able to look at other solvents and molecules with more complex structure, such as ethanol or cyclic compounds, which are of great interest in chemistry and other disciplines,” says Jahnke.

Involved in the study were researchers from the universities of Frankfurt am Main, Freiburg, Hamburg and Kassel as well as Gothenburg, Lund and Uppsala in Sweden and Turku in Finland, from the Fritz Haber Institute of the Max Planck Society and the Max Planck Institute for Nuclear Physics, from Lawrence Berkeley National Laboratory and Kansas State University in the USA, the National Research Council and the Technical University of Milan in Italy, the Sorbonne in Paris, European XFEL and DESY.

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Microplastic pollution aids antibiotic resistance

The Styrofoam container that holds your takeout cheeseburger may contribute to the population’s growing resistance to antibiotics.

According to scientists at Rice University’s George R. Brown School of Engineering, discarded polystyrene broken down into microplastics provides a cozy home not only for microbes and chemical contaminants but also for the free-floating genetic materials that deliver to bacteria the gift of resistance.

A study in the Journal of Hazardous Materials describes how the ultraviolet aging of microplastics in the environment make them apt platforms for antibiotic-resistant genes (ARGs). These genes are armored by bacterial chromosomes, phages and plasmids, all biological vectors that can spread antibiotic resistance to people, lowering their ability to fight infections.

The study led by Rice civil and environmental engineer Pedro Alvarez in collaboration with researchers in China and at the University of Houston also showed chemicals leaching from the plastic as it ages increase the susceptibility of vectors to horizontal gene transfer, through which resistance spreads.

“We were surprised to discover that microplastic aging enhances horizontal ARG,” said Alvarez, the George R. Brown Professor of Civil and Environmental Engineering and director of the Rice-based Nanotechnology Enabled Water Treatment Center. “Enhanced dissemination of antibiotic resistance is an overlooked potential impact of microplastics pollution.”

The researchers found that microplastics (100 nanometers to five micrometers in diameter) aged by the ultraviolet part of sunlight have high surface areas that trap microbes. As the plastics degrade, they also leach depolymerization chemicals that breach the microbes’ membranes, giving ARGs an opportunity to invade.

They noted that microplastic surfaces may serve as aggregation sites for susceptible bacteria, accelerating gene transfer by bringing the bacteria into contact with each other and with released chemicals. That synergy could enrich environmental conditions favorable to antibiotic resistance even in the absence of antibiotics, according to the study.

Co-authors of the paper are Rice graduate student Ruonan Sun; former Rice postdoctoral researcher Pingfeng Yu, now a faculty member at Zhejiang University; associate professor Qingbin Yuan, Yuan Cheng and lecturer Wenbin Wu of Nanjing Tech University, and Jiming Bao, a professor of electrical and computer engineering at the University of Houston.

The Natural Science Foundation of Jiangsu Province (BK20201367), National Natural Science Foundation of China (42177348) and National Science Foundation funding of NEWT (1449500) supported the research.

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Materials provided by Rice University. Original written by Mike Williams. Note: Content may be edited for style and length.

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Covid-19: Italy tightens restrictions for unvaccinated

A so-called Super Green Pass will be needed to access theatres, cinemas and restaurants.

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Sarah Gilbert: Next pandemic could be more lethal than Covid

More funding is needed to prepare for pandemics and prevent gains from being lost, Dame Sarah Gilbert says.

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Covid: Travel changes too late to halt potential new wave – scientist

The return of pre-departure Covid tests for travellers to the UK will come into force on Tuesday.

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Nasal problem plagued long-nosed crocodile relatives

Research published in the journal Anatomical Record finds that humans have more in common with endangered crocodiles than we think — namely, a deviated septum.

Gharials are some of the rarest crocodylians on Earth and members of a group of animals that once roamed the planet with the dinosaurs. Native to India, gharials resemble American alligators and crocodiles, but with bulging eyes and an extremely long and thin snout that allows them to cut through water when hunting prey. In males, this snout houses an even longer nose that ends in an enlarged bulb.

At first glance, these unusual animals appear to have little in common with humans. However, a new study led by Jason Bourke, Ph.D., assistant professor of basic sciences at the College of Osteopathic Medicine at Arkansas State University (NYITCOM-Arkansas), reports that — just like humans — gharials suffer from nasal septal deviation.

The Cleveland Clinic estimates that up to 80 percent of people have a deviated septum, a condition in which the nasal cartilage is “off-center.” While the condition is mild in most individuals, larger deviations can restrict nasal breathing and require reconstructive surgery.

Bourke and his colleagues are the first to document deviated nasal septa in crocodylians. Using medical imaging technology, they analyzed the heads of multiple gharial specimens, including that of a large female from the Fort Worth Zoo nicknamed “Louise,” which fueled their curiosity.

“This weird nasal septum was an unexpected discovery,” said study co-author Casey Holliday, Ph.D., associate professor of pathology and anatomical sciences at the University of Missouri, who initially scanned the specimen for a separate project on gharial anatomy. “I saw this roller coaster of a septum and wondered what this might mean for respiration.”

Holliday shared Louise’s extreme anatomy with Bourke, a vertebrate paleontologist whose lab specializes in modeling fluid dynamics in animal noses using sophisticated computer software that simulates air movement.

“We know remarkably little about normal gharial anatomy, much less their pathology. I couldn’t pass up such a unique opportunity,” said Bourke, who has also studied nasal airflow and thermoregulation in dinosaurs.

Intrigued, Bourke and the team began collecting samples from other gharial specimens housed in zoos around the country. While some specimens showed minor septal deviations, Louise had the most extreme case.

Like humans who experience severe nasal septum deviation, Louise had to work harder to achieve the same breathing rate as her peers. This produced high shearing stresses along the nasal walls, which may have made the animal more prone to nosebleeds. Despite the physiological challenges produced from this nasal pathology, Louise successfully made it to adulthood and lived to the ripe old age of 50.

“It’s a testament to crocodylian resiliency,” said Bourke. “A human with this pathology would need surgery to fix it, but these critters just keep on going.”

In contrast to humans, the researchers found that gharial septal deviation comes with a unique twist. “When the septum deviates in humans, a part or all of the septum bows into one of the airways,” said Nicole Fontenot, fourth-year NYITCOM student, and study co-author. “In our gharials, the septum is so long that it wiggles back and forth along the snout, creating a wavy pattern.”

While this pathology is not found in other modern crocodylians, in the distant past, many other animals showed similarly stretched-out noses, including crested, duck-billed dinosaurs like Parasaurolophus and strange crocodile-mimicking reptiles known as champsosaurs. Bourke suspects that at least a few of them would have also suffered from nasal septum deviations. As for why other crocodylians don’t seem to be as prone to these deviated noses, Bourke explains:

“Other crocodylians have wider snouts with much thicker nasal septa. Thinning out the snout places a premium on space inside the nose. Gharials’ long and very thin nasal septa probably don’t need much to make them start wobbling.

Next, the researchers will continue their investigation by examining the sound-producing abilities of gharials’ unique noses.

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Probiotics improve nausea and vomiting in pregnancy

In a first-of-its-kind study, researchers at the UC Davis School of Medicine found that probiotics significantly improve the symptoms of pregnancy-related nausea, vomiting and constipation. The findings were published in the journal Nutrients.

Nausea and vomiting affect about 85% of pregnancies and can significantly impact quality of life, particularly during early pregnancy.

“The cause of nausea and vomiting during pregnancy is unknown to this date. Various theories have been proposed, but none of them is conclusive,” said Albert T. Liu, lead author for the study and a professor of obstetrics and gynecology.

“Nausea, vomiting and constipation during pregnancy can significantly diminish the quality of patients’ lives. Once nausea and vomiting during pregnancy progress, they can become difficult to control, and sometimes the patient even needs to be hospitalized,” Liu said.

Beneficial microbes

Probiotics are referred to as “beneficial bacteria.” They can be found in foods like yogurt, kimchi, kefir, sauerkraut and tempeh. Probiotics are also available as food supplements. According to the National Center for Complementary and Integrative Health, other than vitamins, probiotics or prebiotics were the third most commonly used dietary supplement for adults.

Probiotics are thought to support the community of different microbes, often referred to as the “gut microbiome,” found in the gastrointestinal tract.

During pregnancy, hormones like estrogen and progesterone increase, bringing about many physical changes. These increases can also change the gut microbiome, which likely affects the digestive system functions and causes unwanted symptoms like nausea, vomiting and constipation.

The researchers set out to determine whether supplementing with a probiotic could be beneficial for gastrointestinal function during pregnancy.

The study lasted for 16 days. A total of 32 participants took a probiotic capsule twice a day for six days and then took two days off. They then repeated the cycle.

The probiotics were available over-the-counter and mainly containedLactobacillus., a type of good bacteria. Each capsule contained approximately 10 billion live cultures at the time of manufacture.

Participants kept 17 daily observations of their symptoms during the duration of the study, for a total of 535 observations for the researchers to statistically assess.

What the researchers found was that taking the probiotic significantly reduced nausea and vomiting. Nausea hours (the number of hours participants felt nauseous) were reduced by 16%, and the number of times they vomited was reduced by 33%. Probiotic intake also significantly improved symptoms related to quality of life, such as fatigue, poor appetite and difficulty maintaining normal social activities, as scored by questionnaires.

Probiotics were also found to reduce constipation significantly.

“Over the years, I’ve observed that probiotics can reduce nausea and vomiting and ease constipation. It’s very encouraging that the study proved this to be true,” said Liu. “Probiotics have also benefited many of my other patients who weren’t in the study,” said Liu.

New clues from gut microbes and byproducts

Participants also contributed fecal specimens before and during the study. The samples were analyzed to identify the type and number of microbes and the different byproducts of digestion.

This allowed the researchers to examine whether biomarkers in the fecal specimens corresponded with more severe nausea and assess how the probiotics affected participants who began the study with different baseline biomarkers.

One finding was that a low amount of bacteria that carry an enzyme named bile salt hydrolase, which generates bile acid to absorb nutrients, was associated with more pregnancy-related vomiting. Probiotics increase bile salt hydrolase-producing bacteria, which may explain why the supplements decreased levels of nausea and vomiting.

Another finding was that high levels of the gut microbes Akkermansia and A. muciniphila at the beginning of the study were associated with more vomiting. The probiotic significantly reduced the amount of those particular microbes and also reduced vomiting. This suggests Akkermansia and A. muciniphila may be reliable biomarkers that can predict vomiting in pregnancy.

Another finding was that vitamin E levels increased after taking probiotics. Higher levels of vitamin E were associated with low vomiting scores.

“This research provides key insights about the impact of gut microbes on gastrointestinal function during pregnancy. Our gut microbiota explains why we are what we eat, and why bacteria-generated metabolites and products have a huge impact on our health,” said Wan. “They affect the gastrointestinal tract as well as skin health and neurological function.”

Although the findings are intriguing, the researchers caution that due to the small sample size, further studies will be needed to confirm the effects of the probiotics.

“Our previous work showed the benefits of probiotics in preventing liver inflammation. The current study might be one of the first to show the benefits of probiotics in pregnancy,” said Wan. “It would be interesting and important to further test whether probiotics can reduce nausea and vomiting caused by chemotherapy in cancer patients.”

Additional authors on this study include Shuai Chen from the Department of Public Health Sciences, and Prasant Kumar Jena, Lili Sheng and Ying Hu from the Department of Pathology and Laboratory Medicine at the University of California, Davis.

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How you speak up at work can affect whether you’re picked for a team

Business leaders and management experts often encourage people to speak up in the workplace. Suggesting a creative idea or a more efficient way to work can help companies overcome challenges and meet goals. But new research shows another, more subtle and often overlooked form of speaking up has a big effect on the way work gets done and how teams come together.

“What we say within a group, the ideas we suggest and the way we support others, signals something about who we are to our coworkers. It can attract people to us or repel them,” said Melissa Chamberlin, assistant professor of management and entrepreneurship at Iowa State University, and co-author of a paper recently published in Journal of Management.

In the paper, Chamberlin and her research team demonstrate how two different ways of communicating work-related issues shape reputations and affect the formation of teams to complete short-term projects. They found people who use “supportive voice,” which fuels trust and cooperation, have a higher chance of being recruited to a team compared to those who use a more task-oriented “challenging voice.”

Challenging voice pushes back against the status quo and offers ideas for improvement. While it has some downsides, such as perceived criticism or conflict, challenge voice tends to signal an employee’s competence or expertise. Chamberlin said managers, especially in dynamic and fast-paced industries, often value this communication behavior as something that can help teams complete tasks efficiently and effectively.

“Supportive voice is still about speaking up in the workplace, but it’s looking at what’s going well in the group or team. It might defend the status quo by saying there’s value in what the team is already doing,” said Chamberlin.

Supportive voice signals someone’s approachability and trustworthiness. It fosters strong interpersonal relationships, which Chamberlin said affects a team’s ability to communicate and coordinate efforts in order to reach goals.

To understand the effects of the two communication behaviors on team formation, the researchers collected data from a cohort of full-time, first-year Master of Business Administration students over a four-month period. The students were periodically assigned to different teams to complete projects and then asked to rate fellow team members’ use of challenging and supportive voice, quality of work, reputation and trust. Near the end of the study, students were allowed to assemble into teams without any direction from the MBA office.

The study results revealed students who ranked high on challenging voice built a reputation for conducting high-quality work, but students preferred to work in teams with those who frequently used supportive voice. Chamberlin said the results were surprising.

“Because challenging voice is the predominant form of speaking up we encourage in classrooms and as managers, we thought it was going to be strong driver of people selecting team members later. But as it turns out, this more supportive voice that helps establish relationships and a sense of trust amongst individuals in the group was more important,” Chamberlin said.

The researchers pointed out that having both types of voice would be ideal, but between the two, supportive voice was a stronger driver of team formation.

Chamberlin said the paper’s findings could help employees realize the way they speak up can have a strong effect on informal teaming up at a later point and help them move into leadership roles. As for managers, Chamberlin said the results could encourage them to foster and provide space for more supportive voice by coaching this type of behavior and rewarding employees who speak up supportively.

“There might be times that challenging voice reigns supreme but other situations where supportive voice becomes more critical for a team,” said Chamberlin. “Supportive voicers can keep teams together to make sure the work gets done.”

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Materials provided by Iowa State University. Note: Content may be edited for style and length.

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Covid: Doctors’ leaders back postponed health checks

A senior GP says the move would support the “national priority” to vaccinate people quickly.

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