Monday, October 21, 2024

 

Why do we love carbs? The origins predate agriculture and maybe even our split from Neanderthals



Study co-led by UB finds the gene for starch-digesting saliva may have first duplicated more than 800,000 years ago, seeding the genetic variation that shapes our modern diet



University at Buffalo

Omer Gokcumen lab 

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The lab of Omer Gokcumen helped analyze the genomes of 68 ancient humans for answers about our ability to begin breaking down starch in the mouth.

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Credit: Meredith Forrest Kulwicki/University at Buffalo





BUFFALO, N.Y. — If you’ve ever struggled to reduce your carb intake, ancient DNA might be to blame.

 It has long been known that humans carry multiple copies of a gene that allows us to begin breaking down complex carbohydrate starch in the mouth, providing the first step in metabolizing starchy foods like bread and pasta. However, it has been notoriously difficult for researchers to determine how and when the number of these genes expanded.

Now, a new study led by the University at Buffalo and the Jackson Laboratory (JAX), reveals how the duplication of this gene — known as the salivary amylase gene (AMY1) —may not only have helped shape human adaptation to starchy foods, but may have occurred as far back as more than 800,000 years ago, long before the advent of farming.

Reported today in the Oct. 17 advanced online issue of Science, the study ultimately showcases how early duplications of this gene set the stage for the wide genetic variation that still exists today, influencing how effectively humans digest starchy foods.

“The idea is that the more amylase genes you have, the more amylase you can produce and the more starch you can digest effectively,” says the study's corresponding author, Omer Gokcumen, PhD, professor in the Department of Biological Sciences, within the UB College of Arts and Sciences. 

Amylase, the researchers explain, is an enzyme that not only breaks down starch into glucose, but also gives bread its taste.

 Gokcumen and his colleagues, including co-senior author, Charles Lee, professor and Robert Alvine Family Endowed Chair at JAX, used optical genome mapping and long-read sequencing, a methodological breakthrough crucial to mapping the AMY1 gene region in extraordinary detail. Traditional short-read sequencing methods struggle to accurately distinguish between gene copies in this region due to their near-identical sequence. However, long-read sequencing allowed Gokcumen and Lee to overcome this challenge in present-day humans, providing a clearer picture of how AMY1 duplications evolved.

Ancient hunter-gatherers and even Neanderthals already had multiple AMY1 copies

Analyzing the genomes of 68 ancient humans, including a 45,000-year-old sample from Siberia, the research team found that pre-agricultural hunter-gatherers already had an average of four to eight AMY1 copies per diploid cell, suggesting that humans were already walking around Eurasia with a wide variety of high AMY1 copy numbers well before they started domesticating plants and eating excess amounts of starch.

The study also found that AMY1 gene duplications occurred in Neanderthals and Denisovans. 

“This suggests that the AMY1 gene may have first duplicated more than 800,000 years ago, well before humans split from Neanderthals and much further back than previously thought,” says Kwondo Kim, one of the lead authors on this study from the Lee Lab at JAX.

“The initial duplications in our genomes laid the groundwork for significant variation in the amylase region, allowing humans to adapt to shifting diets as starch consumption rose dramatically with the advent of new technologies and lifestyles,” Gokcumen adds.

The seeds of genetic variation

The initial duplication of AMY1 was like the first ripple in a pond, creating a genetic opportunity that later shaped our species. As humans spread across different environments, the flexibility in the number of AMY1 copies provided an advantage for adapting to new diets, particularly those rich in starch.

“Following the initial duplication, leading to three AMY1 copies in a cell, the amylase locus became unstable and began creating new variations," says Charikleia Karageorgiou, one of the lead authors of the study at UB. “From three AMY1 copies, you can get all the way up to nine copies, or even go back to one copy per haploid cell.”

The complicated legacy of farming

The research also highlights how agriculture impacted AMY1 variation. While early hunter-gatherers had multiple gene copies, European farmers saw a surge in the average number of AMY1 copies over the past 4,000 years, likely due to their starch-rich diets. Gokcumen’s previous research showed that domesticated animals living alongside humans, such as dogs and pigs, also have higher amylase gene copy numbers compared to animals not reliant on starch-heavy diets.

“Individuals with higher AMY1 copy numbers were likely digesting starch more efficiently and having more offspring,” Gokcumen says. “Their lineages ultimately fared better over a long evolutionary timeframe than those with lower copy numbers, propagating the number of the AMY1 copies.”

The findings track with a University of California, Berkeley-led study published last month in Naturewhich found that humans in Europe expanded their average number of AMY1 copies from four to seven over the last 12,000 years.

“Given the key role of AMY1 copy number variation in human evolution, this genetic variation presents an exciting opportunity to explore its impact on metabolic health and uncover the mechanisms involved in starch digestion and glucose metabolism,” says Feyza Yilmaz, an associate computational scientist at JAX and a lead author of the study. “Future research could reveal its precise effects and timing of selection, providing critical insights into genetics, nutrition, and health.”

Other UB authors on the study include PhD students Petar Pajic and Kendra Scheer.

The research was a collaboration with the University of Connecticut Health Center and was supported by the National Science Foundation and the National Human Genome Research Institute, National Institutes of Health.

 

Drones prove effective way to monitor maize re-growth, researchers report



Journal of Remote Sensing
Aerial view of maize lodging experiment 

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Researchers used unmanned aerial vehicle to conduct a survey of maize lodging experiments in Hebei Province.

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Credit: Qian Sun, Yangzhou University




Maize, or corn, grows tall, with thin stalks that boast ears of the cereal grain used in food production, trade and security globally. However, due to rain, wind and other increasingly extreme weather events, the maize falls down, risking the entire crop. Called lodging, the physical fall results in shorter plants and overlapping leaves — both of which negatively impact the plant’s ability to grow.

 

Conventional lodging prevention and mitigation requires many agricultural technicians significant time to investigate the crop fields, according to a team of researchers based in China. They said that a potential solution could be a rapid, non-destructive method of remote monitoring, called Unmanned Aerial Vehicle (UAV)-based hyperspectral imaging. The team recently found that the method can accurately evaluate maize recovery without the time or expense of individuals physically inspecting the crops.

 

The team published their approach on Aug. 28 in the Journal of Remote Sensing.  

 

“UAV-based hyperspectral imaging technology revolutionizes the way we monitor and assess the recovery of lodging crops,” said first author Qian Sun, a doctor at Yangzhou University. “This advanced method allows for rapid, non-destructive evaluation of plant health and growth. This not only aids in better understanding the state of plants but also enhances overall crop management practices, potentially leading to more effective interventions and improved agricultural production.”

 

UAV-based hyperspectral imaging involves using drone-like vehicles that can fly with limited human input and examine the field. For every pixel in an image, the method determines the multiple spectral bands — a much more detailed understanding than human eyesight, which only sees across three bands of visible light.

 

The researchers used UAV-based hyperspectral imaging to assess canopy height and coverage, as well as physiological activity of maize, such as chlorophyll production — evidence of photosynthesis, an energy-producing process that may reduce if stalks are shorter or leaves are obscured by other plants after lodging. This two-prong approach is necessary for accurate assessment, the researchers said, as measuring just one variable provides an incomplete picture of the maize’s regrowth progress.

 

“This technique allows for more precise monitoring and assessment of lodging crop conditions compared to traditional methods,” said co-corresponding author Xiaohe Gu, a professor with the Research Center of Information Technology, Beijing Academy of Agriculture and Forestry Sciences. “In particular, this study proposed a comprehensive evaluation framework that combines the canopy structure and the physiological activity, delivering a precise and efficient means of assessing the recovery grades of lodging maize.”

 

They determined that their imaging approach could accurately assess both the canopy stature and the physiological activity, providing information to farmers who could then make adjustments to the crops to assist in their recovery.

 

“The ultimate goal is to revolutionize agricultural practices through the widespread adoption of UAV-based hyperspectral technology,” said co-author author Liping Chen, a professor with the Research Center of Information Technology, Beijing Academy of Agriculture and Forestry. “By making this advanced tool a standard component in crop monitoring, we aim to significantly enhance the accuracy and efficiency of assessing plant health and recovery. This will enable farmers and agronomists to manage crops more effectively, optimize interventions, and ultimately increase yield and productivity.”

 

Other co-authors on the study are Baoyuan Zhang, Xuxhou Qu and Yanglin Cui, all with the Research Center of Information Technology, Beijing Academy of Agriculture and ForestrySciences ; and co-corresponding author Meiyan Shu, College of Information and Management Science at Henan Agricultural University.

The National Key Research and Development Program of China supported this work.

 

 

 

Materials of the future can be extracted from wastewater



A group of researchers is on the way to revolutionizing what biomass from wastewater treatment plants can be used for. Biopolymers from bacteria can be a sustainable alternative to oil-based products, and phosphorus and other minerals can also be harvested



Peer-Reviewed Publication

Aalborg University





"The perspective is enormous, because you’re taking something that is currently waste and making high-value products from it."

 

This is what Professor Per Halkjær Nielsen, Department of Chemistry and Bioscience at Aalborg University in Denmark, says about the results of a research project that utilizes surplus biomass in wastewater treatment plants in new ways. The focal point is biopolymers that can be described as long chains of molecules that are bound to each other and that are produced by living organisms, including bacteria. Today, synthetic polymers produced in the petrochemical industry from crude oil are used in many contexts including plastics, textile fibres, adhesives and paints. But with future production of biopolymers at wastewater treatment plants, it will be possible to extract a sustainable alternative to oil-based polymers through a waste product.

 

"In short, the work on biopolymers is about producing a lot of biomass in wastewater treatment plants that is actually bacteria that eat everything that enters the treatment plant so that only the pure water remains," explains Professor Per Halkjær Nielsen.

"Every single day, many tons of biomass are produced, depending on how big the treatment plant is, and this is typically converted in a biogas reactor so that you get energy out of it. A large part of the bacteria consists of biopolymers, i.e. the adhesive material around them, and biopolymers are in demand in the industry as a sustainable alternative to oil-based polymers."

 

Biopolymers can be used as a binding agent in paper and in building materials, and they can be used as a material for flocculation where small particles clump together and settle as part of the water purification of harbour sludge, lakes and wastewater treatment plants. An added bonus is that biopolymers from wastewater treatment plants appear to be fire-retardant. Thus, there is a potentially large market for biopolymers if they can be produced commercially in a sustainably way, and there is potential for this, according to the research project REThiNk.

 

In a wastewater treatment plant, there are several hundred different species of bacteria that produce many types of biopolymers with different properties. These bacteria use the biopolymers as an adhesive to form colonies and adhere to surfaces so they are not just flushed out of the treatment plant. These biopolymers can be extracted by changing the pH and temperature of the water to produce cellulose and gelatinous biopolymers that can be used for a variety of industrial products. The expectation is that it will be possible to create factories that produce biopolymers from Danish wastewater treatment plants, and the potential is great, since hundreds of thousands of tons of bacteria are produced annually in Denmark alone. As an added benefit, minerals and other valuable components can be harvested from the wastewater that arrives at the treatment plants, such as phosphorus which is on the EU's list of critical raw materials that may be difficult to obtain in the future.

 

The goal of the REThiNk project is to create the foundation for industrial scale-up in the short term so that in the long term there will be a real revolution in recycling biomass from wastewater treatment plants all over the world and not just in Denmark. It also requires mapping bacteria at wastewater treatment plants around the world so that it is possible to predict how each of them can play a role in biopolymer production, phosphorus extraction, etc.

 

"There is great potential if companies can see that the product can be used for something and thus want to invest in testing and developing it. And this requires that we build pilot scale plants so that we can produce not just grams, but kilograms and in a few years' time many tons. We can take 20-30 percent of the biomass and turn it into biopolymers that can replace petroleum products, but it actually also replaces seaweed. Today, many biopolymers are produced from seaweed from large kelp forests that are endangered. So if we can find other ways to extract biopolymers, it is a clear advantage for the environment and biodiversity as well," Per Halkjær Nielsen points out.

 

In the REThiNk project, Aalborg University is collaborating with Delft University in the Netherlands and Aarhus University, and the researchers have just published their results in the scientific journal Current Opinion in Biotechnology.

 

More information:

  • Read more about the research project REThiNk (Recovery of extracellular polymers from wastewater treatment residuals as a new circular biopolymer): https://www.en.bio.aau.dk/research/projects/rethink
  • Article in the journal Current Opinion in Biotechnology, October 2024: "Rethinking characterization, application, and importance of extracellular polymeric substances in water technologies" (https://www.sciencedirect.com/science/article/pii/S0958166924001289)
  • About biopolymers: Polymers are substances that consist of molecules bonded to each other in long molecular chains. Biopolymers are formed by living organisms, one of the best known being cellulose from trees and plants. Synthetic polymers are artificially produced in the petrochemical industry based on crude oil and are used in plastics, textile fibres, adhesives and paints, among other things. The physical properties of polymers have an impact on what they can be used for (source: Lex.dk, https://denstoredanske.lex.dk/polymer). 

 

 

American lobster population, habitat preferences shifting, study finds



University of Maine
LobsterOnSediment 

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A Lobster is in a featureless sediment habitat in the Gulf of Maine. 

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Credit: Photo by Katherine Burnham.




American lobsters along Maine’s coast have relocated to new habitats, while the population simultaneously shrunk in abundance and grew older, according to a new study by University of Maine researchers.

For decades, the vast majority of adult lobsters resided in boulder shelter habitats. This knowledge helped inform longtime conservation efforts and regulations within the more than $740 million fishery. 

A team of UMaine scientists, however, found that from 1995-2021, occupancy of boulder habitats dropped 60%. Meanwhile, the number of lobsters residing in sediment or featureless ledge habitats, both of which have little to no geological features to use as shelters, increased 633% and 280%, respectively. Lobster population density across all types of habitats declined too, meaning they are fewer in number and their populations are more spread out. 

Water temperatures increased nearly 3 degrees Celcius from 1995-2021 across these habitats, according to researchers, showing how lobsters and their habitats are changing with the climate. Kelp abundance declined across lobster habitats, while diminutive algal turfs — small green mats containing multiple species of algae — increased.

“These differences in the way lobsters use their habitats provide context for the lobster stock assessment that helps to determine the health of the entire lobster population,” said Robert Jarrett, lead author of the study and marine biology Ph.D. student. “Some of the annual lobster surveys used in the assessment, like those from the Maine Department of Marine Resources, are restricted in the types of habitats that they can sample, so these findings about habitat help fill in some information gaps and show that over time the lobsters may be shifting between which surveys catch them better.” 

Jarrett and his colleagues published their findings in the journal Marine Ecology Progress Series. Co-authors include Damian Brady, Agatha B. Darling Professor of Oceanography; Richard Wahle, former director of the Lobster Institute, and Bob Steneck, professor emeritus of oceanography, marine biology and marine policy.

The team investigated 20 sites along Maine’s coast, from York to Jonesport. They dove 10 meters below the surface to count and measure lobster, as well as to collect data on habitat and temperature. The team also reviewed historic data for the same sites dating back to the 1990s. 

While overall population density has declined, the mean size of an adult lobster was greater in 2021 than in 1996. According to the study, the increase in mean size is partially the result of fewer juvenile lobsters residing in these habitats. While lobsters in the Gulf of Maine are now larger, the team observed that the majority, or 93%, were still smaller than 83 millimeters, the minimum legal size to be caught and sold — a promising sign for the fishery. 

Lobsters are also now favoring open spaces within their habitats over rocky shelters than previously. The percentage of lobsters living under rocky shelters dropped 34% from 2000-2019, while those using no shelter at all increased 168%. The number of lobsters that reside underneath beds of algae have also grown 160%.

According to researchers, demographic shifts among Gulf of Maine lobsters — habitat, size and population density — may have resulted from a drop in baby lobsters surviving to the seafloor and less competition between individual lobsters. The lack of predators might have also influenced more lobsters to move away from boulders to more open habitats, forgoing rock shelters for cover with only algae to hide under.   

“When you consider that this is one of the best studied commercially important marine species in the world, it is stunning that we keep getting surprised by our iconic lobster,” Steneck said.

This study is the latest example of how UMaine students and faculty are preserving and propelling the state’s blue economy, industries that use ocean resources for economic growth without jeopardizing the environment. 

Through innovation and workforce development, the university broadens insight into ecological and sociological changes that affect the state’s coastal communities and businesses. Its faculty and students are also exploring opportunities for new sectors and markets and investigating potential resources to mitigate the ramifications of climate change. 

Bolstering these efforts is the UMaine Marine Aligned Research, Innovation, and Nationally-recognized Education (MARINE) Initiative, which fosters collaboration and synergy among researchers, industry, government and communities. Together, they integrate and innovate transdisciplinary marine research, education and outreach to enhance the socioeconomic well-being of people in Maine and beyond.  

“This study exemplifies how the University of Maine supports Maine’s blue economy. In a changing Gulf of Maine, sustainable management of the largest fishery in North America requires better understanding how lobsters are using habitat” said Brady, also the principal investigator of a National Science Foundation-funded Navigating the New Arctic project that supported this work

Disclaimer: AAAS and EurekAlert

 

New study sheds light on lily toxicity in cats; outpatient treatment may be viable option



Results challenge long-held assumption that hospitalization is always necessary for lily-exposed cats



American Veterinary Medical Association





 

(SCHAUMBURG, Illinois) October 17, 2024—A study published recently in the Journal of the American Veterinary Medical Association (JAVMA) has revealed new insights into the treatment of cats exposed to toxic lilies, offering hope for pet owners facing this common household hazard.

The study (“Prevalence of acute kidney injury and outcome in cats treated as inpatients versus outpatients following lily exposure”), conducted at the University of Pennsylvania School of Veterinary Medicine, investigated the outcomes of 112 cats treated for lily exposure, comparing cats treated as inpatients with intravenous fluids to those managed as outpatients with subcutaneous fluids.

Contrary to previous beliefs, the study found no significant difference in the prevalence of acute kidney injury (AKI) between inpatient (46.9%) and outpatient (43.8%) groups. This challenges the long-held assumption that hospitalization with intravenous fluids is always necessary for lily-exposed cats and marks a significant step forward in understanding and managing lily toxicity in cats, potentially expanding treatment options and improving outcomes for feline patients.

"Our findings suggest that outpatient management may be a viable option for some cats exposed to lilies," says Dr. Erica Reineke, professor of emergency and critical care, University of Pennsylvania School of Veterinary Medicine, and one of the authors of the study. "This could be particularly relevant for pet owners with financial limitations, lack of access to 24-hour veterinary facilities or other cat specific factors.”

The researchers caution that their findings should not be interpreted as definitive treatment recommendations. Larger, controlled studies are needed to establish evidence-based guidelines for managing lily toxicity in cats.

Dr. Reineke added that the study also revealed a higher overall prevalence of AKI in both groups compared to previous reports. However, many cats with AKI showed improvement or stabilization of their condition, and the overall survival rate was excellent.

While inpatient cats had a 100% survival rate compared to an 87.5% survival rate for outpatient cats, this difference--though statistically significant--suggests that outpatient treatment can still lead to favorable outcomes in many cases.

Dr. Reineke emphasized that “it's crucial for cat owners to understand that all parts of the lily plant are toxic to cats. Prompt veterinary attention is essential, regardless of the treatment approach.”

For cat owners, the study underscores the importance of lily awareness and quick action in case of exposure. It also offers hope that, with proper veterinary guidance, various treatment options may be available depending on individual circumstances.

For more information, contact Michael San Filippo, AVMA senior media relations manager, at 847-732-6194 (cell/text) or msanfilippo@avma.org.

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About the AVMA

Serving more than 105,000 member veterinarians, the AVMA is the nation's leading representative of the veterinary profession, dedicated to improving the health and wellbeing of animals, humans and the environment. Founded in 1863 and with members in every U.S. state and territory and more than 60 countries, the AVMA is one of the largest veterinary medical organizations in the world.

 

 

Nonnative plants are a major force behind global insect invasions, new study finds



American Institute of Biological Sciences





In an article in the journal BioScience, an international team of researchers led by Dr. Cleo Bertelsmeier from the University of Lausanne, Switzerland, argue that the global spread of nonnative plants is a key factor driving the growing number of insect invasions worldwide. The research challenges traditional assumptions about the principal causes of nonnative insect invasions.

The authors note that when nonnative plants become established in new regions, they create ecological niches that permit the establishment of insect species from the plants' native ranges, which can produce further cascading effects: "Plant invasions facilitate insect invasions directly by providing ecological niches for arriving insect herbivores, and indirectly by favoring the establishment of insect predators and parasitoids," resulting in a cascade of effects described as an "invasional meltdown."

Bertelsmeier and colleagues synthesize multiple lines of evidence to analyze insect invasions, finding that global flows of invasive plants are more tightly linked to insect invasions than are other factors, such as global trade or propagule pressure. "Macroecological analyses support the hypothesis that nonnative plant richness is a major determinant of nonnative insect richness," they say.

These findings have important implications for biosecurity and invasive species management, fields in which future success will depend on appropriately addressing the complex dynamics driving biological invasions in our increasingly interconnected world.

While current practices focus heavily on preventing new insect arrivals, the authors argue that more attention should be paid to limiting the spread of nonnative plants, say the authors: "Controlling the spread of undesired nonnative plant species would not only be beneficial because it mitigates the impacts of the plant species themselves, it would also reduce spillover of associated nonnative insects to native plant species."