Heterogeneity in host populations drives the evolution of more virulent pathogens

The Graduate University for Advanced Studies, SOKENDAI

 

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Contrast between idealized homogeneous and realistic heterogeneous metapopulations

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Credit: ©SOKENDAI, AIST, OIST

The evolution of pathogens has received attention in a wide range of scientific fields, such as epidemiology, demography, and evolutionary ecology. Understanding pathogen evolution is particularly urgent for rapidly evolving pathogens, such as SARS-CoV-2, which has spread globally since 2019. Classical evolutionary theory states that virulence evolves to maximize a pathogen’s basic reproduction ratio, i.e., the average number of secondary infections caused by one infected host. This approach provides insights into how pathogen virulence evolves under tradeoffs with other epidemiological parameters such as the rates of infection and recovery. Over time, the classical theory has been extended to a variety of ecological and epidemiological contexts.

Despite these advancements, most models continue to assume homogeneous host populations, thereby neglecting the impacts of all environmental heterogeneity. In reality, however, ecosystems often represent interconnected local populations that experience different local conditions, as described by ecological metapopulation theory (Figure 1). Moreover, the movement patterns of host individuals connecting these local populations also tend to be heterogeneous, and such imbalances in movement among local populations creates a “source-sink” structure, with some populations (sources) creating a net outflow and other populations (sinks) receiving a net inflow. To address this gap, we have developed an evo-eco-epidemiological metapopulation model to investigate how heterogeneity in local environments and movement networks influences the evolution of pathogen virulence and infectivity, providing new insights into the evolution of pathogens in diverse ecological contexts.

Our analyses reveal that pathogen virulence consistently increases in metapopulations with heterogeneous local conditions. Even with modest heterogeneities (10% variation) in host movement rates, birth rates, carrying capacities, or immunity-loss rates, the evolved virulence is, on average, 20% higher—and up to 40% higher—compared to homogeneous metapopulations (Figure 2).

Why does environmental heterogeneity drive the evolution of higher pathogen virulence and infectiousness? Through perturbation-expansion methods and evolutionary dynamical analysis, we have uncovered the underlying general mechanism. Heterogeneity creates variation across local populations in the availability of uninfected hosts, which serve as resources for pathogens in their quest to infect new hosts, and it is ultimately this variation that promotes the evolution of more virulent pathogens. For instance, in local populations with higher carrying capacity, host density is elevated, creating a “richer” environment that favors aggressive pathogens. These pathogens cause more severe symptoms, are more highly infectious, and exploit their hosts more rapidly. In contrast, in local populations with lower carrying capacity, host density is diminished, which is limiting the availability of uninfected hosts. Here, milder pathogens are favored evolutionarily, as they can better persist under such resource-scarce conditions.

However, these opposing local evolutionary trends do not balance out in the evolution of pathogens across a metapopulation. Pathogens in resource-rich populations produce more infections and contribute more significantly to the gene pool of the metapopulation, and thus have higher evolutionary importance. This results in an evolutionary bias toward higher virulence, as the selection for aggressive pathogens outweighs the selection for milder ones. Consequently, environmental heterogeneity consistently drives the evolution of higher pathogen virulence across metapopulations (Figure 3).

This study establishes a foundation for understanding pathogen evolution in heterogeneous metapopulations, paving the way for various extensions, such as continuously spatially structured host populations, distributed public-health interventions, and diverse pathogen-transmission modes, including zoonoses and vector-borne infections.

 Evolved virulence in metapopulations with randomly generated heterogeneous local environments. 

Evolved virulence is consistently higher in heterogeneous metapopulations compared to homogeneous metapopulations. Each point represents the evolved virulence in a metapopulation with randomly generated local environments that are heterogenous in terms of movement rates, birth rates, carrying capacities, or immunity-loss rates. The horizontal lines indicate the resultant average increases in the evolved virulence.

 Mechanism explaining why heterogeneities in host metapopulations cause the evolution of elevated pathogen virulence 

Heterogeneities in local environments create heterogeneity in the densities of local host populations. The left population is “resource-rich” for pathogens, as it offers a higher density of susceptible hosts, while the right population is “resource-scarce”, as it offers a lower density of susceptible hosts. For higher susceptible-host densities, more virulent pathogens are favored, while for lower susceptible-densities, milder pathogens are favored. Crucially, the net effect of these selection pressures across the metapopulation is not balanced, as the resource-rich population makes a more significant evolutionary contribution than the resource-scarce population, causing evolution to drive up pathogen virulence and infectiousness.

Credit

©SOKENDAI, AIST, OIST

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Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2309272121 

Method of Research

Computational simulation/modeling

Subject of Research

Animals

Article Title

Heterogeneity in Host Populations Drives the Evolution of More Virulent Pathogens

Article Publication Date

19-Dec-2024

 GNOSIS; THE NOSE KNOWS

Biosensors based on olfactory receptors to decipher the human sense of smell

The system makes it possible to discriminate between odours with very similar characteristics based on the binding interaction with the receptor, which causes a change in the capacitive response of the receptor.

Institute for Bioengineering of Catalonia (IBEC)

 

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Anna Lagunas (left) and Josep Samitier (right) at IBEC laboratories.

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Credit: Institute for Bioengineering of Catalonia (IBEC)

The human olfactory system discriminates between thousands of odours by interacting specifically with olfactory receptors on sensory neurons. Each receptor can detect several odorants at different intensities, and the same odorant can activate more than one receptor. This complex combination of signals generates our olfactory perception.

The biological importance of olfaction, which enables us to forage, interact socially and detect danger, has driven the development of olfactory sensors with various industrial applications. Although olfactory receptor-based sensors are very sensitive, detecting concentrations down to the femtomolar level - parts per thousand trillion - they have one limitation: they cannot accurately distinguish between the different odours that trigger them.

In this context, a recent study led by the Institute forBioengineering of Catalonia (IBEC) and the Centre for Biomedical Research Network on Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), in collaboration with the Centre des Sciences Du Goût et de l'Alimentation and the Institut de Chimie de Nice, has developed an innovative method to distinguish between odours that activate the same receptor. This method is based on the detection of small electrical changes in the receptor, known as the capacitive response. These changes are proportional to the strength with which the odorant binds to the receptor, mimicking the physiological response to an odour.

“We have seen that when the receptor comes into contact with one of the compounds, there is a change in the electrical response that is proportional to the strength with which the compound binds to the receptor. This information helps us to better understand how olfactory recognition works at the molecular level and how this knowledge can be used to design more effective sensors,” explains Anna Lagunas, first author of the study and senior researcher in IBEC's Nanobioengineering group led by Josep Samitier.

This innovation is a step forward in the design of more precise sensors, which could have applications in odour screening or in other technological and industrial fields.

Selective detection of odours

For the experiments, a human olfactory receptor (hOR1A1) was immobilised on a gold surface with an antibody to ensure its orientation and improve the sensitivity of the measurements. The three olfactory substances used (dihydrojasmone and two forms of carvone) are agonists of the receptor, i.e. they are all capable of activating it, giving rise to different odours, which makes it possible to simulate real physiological activations.

The study, which also involved IBEC's Nanoprobes and Nanoswitches group led by Pau Gorostiza, explains that the sensor's increased ability to identify substances is due, among other things, to the specific electrical response of the receptor, linked to an intrinsic property called the dipole moment, which varies in the presence of the odorant. The dipole moment is a measure of the distribution of electrical charges within a molecule. In this case, changes in the dipole moment of the receptor when it binds to an odour molecule are key to detecting it.

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Journal

Biosensors and Bioelectronics

DOI

10.1016/j.bios.2024.117000 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Ligand discrimination in hOR1A1 based on the capacitive response

 

A tropical disease in Switzerland: Call for coordinated action on Chagas disease

Swiss Tropical and Public Health Institute

Chagas disease, caused by the parasite Trypanosoma cruzi, affects about 7 to 8 million people worldwide, mainly in Latin America. The parasite can be transmitted by triatomine bugs, via food, blood transfusions and organ donations, as well as from mother to child during pregnancy and birth. Chagas disease has two phases: In the acute phase in the first 2 months, symptoms are mild or absent, though some may have fever, headache or swelling at the bite site. Decades later, in the chronic phase, up to a third of infected individuals develop cardiovascular, digestive and/or neurological problems. Advanced cases can lead to heart complications such as arrhythmias and sudden death. Chagas disease is categorized as a neglected tropical disease (NTD) by the World Health Organization (WHO).

2,000 to 4,000 people in Switzerland affected
A review published yesterday in the Swiss Medical Weekly now sheds light on the prevalence, challenges and management of Chagas disease. The study found that an estimated 2,000 to 4,000 people are affected by this tropical disease. While most of the cases stem from migration, the study also shows that Chagas disease can be transmitted in Switzerland through mother-child transmission during pregnancy and childbirth. The vector – the triatomine bug – is not present in Europe.
“A major problem of Chagas disease is that it is often underdiagnosed, particularly in non-endemic regions,” said Pablo Martinez de Salazar, Senior Scientific Collaborator at Swiss TPH, and last author of the study. “Indeed, many cases remain undiagnosed or undetected for years, potentially resulting in severe cardiac or digestive complications if untreated.” Factors such as limited awareness among healthcare professionals, absence of nationwide screening programmes and barriers to healthcare access – especially for undocumented migrants –, contribute to this underdiagnosis.

Establishment of the Swiss Chagas Network
To address these issues, the study team established the Swiss Chagas Network to eliminate Chagas disease as a public health problem through coordinated measures. The network aims to interrupt transmission and to provide adequate clinical management to people living with Chagas disease in Switzerland.
Key priorities include integrating screening into prenatal and paediatric care for early detection and preventing mother-to-child transmission during pregnancy and childbirth. In line with international guidelines, the Swiss Society for Gynaecology and Obstetrics recently issued an expert letter on Screening, prevention and treatment of congenital Chagas disease.

“Systematic screening in Latin American migrants, with a focus on women of reproductive age, pregnant women and children, will be critical,” said Mar Velarde, Scientific Collaborator at Swiss TPH and co-author of the paper. “If appropriate measures are put in place, Switzerland will be well positioned to achieve the targets of the WHO road map for neglected tropical diseases by 2030 and could become a blueprint for other countries.” The road map sets out global targets to prevent, control, eliminate and eradicate different NTDs by 2030.

About the study
The study was led by Swiss TPH in collaboration with WHO, Unisanté, the University of Lausanne, the School of Health Sciences (HESAV), the University of Applied Sciences and Arts Western Switzerland (HES-SO), the University of Zurich, the University of Basel, the Geneva University Hospital, and the University of Geneva. The coordination of the study was supported by the R. Geigy Foundation.

Swiss TPH expertise in Chagas disease
Swiss TPH has a long tradition of work pertaining to neglected tropical diseases, from basic research to training, diagnosis, treatment and elimination efforts. With regards to Chagas disease, Swiss TPH is involved in drug discovery, drug development, epidemiology, diagnosis, control and elimination.

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Journal

Swiss Medical Weekly

DOI

10.57187/s.3719 

Subject of Research

People

Article Title

Chagas disease in Switzerland: current situation, challenges and opportunities

Article Publication Date

19-Dec-2024

 

New study reveals economic burden of tooth decay is highest in deprived groups

Preventative measures focusing on the most deprived groups could have significant potential for cost savings

University of Birmingham

The economic impact of dental caries (tooth decay) is disproportionately higher in the most deprived groups, with estimated per-person costs of approximately £18,000 in the UK that could be dramatically reduced with targeted preventative measures, found new research.

The study, published in BMC Public Health and commissioned by the European Federation of Periodontology (EFP), examined inequalities in oral health by estimating the economic burden of dental caries by deprivation status in six countries. An international research team, including Professor Moritz Kebschull and Professor Iain Chapple from the University of Birmingham’s School of Dentistry, developed a simulation model to study the healthcare costs associated with managing dental caries from adolescence to middle age in the UK, Brazil, France, Germany, Indonesia, and Italy.

The model was based on national-level data about decayed, missing and filled teeth, the relative likelihood of receiving an intervention (such as a restorative procedure, tooth extraction and replacement), and clinically guided assumptions for different socioeconomic groups. The findings reveal that the economic impact of dental caries is disproportionately higher in the most deprived groups, with the UK showing the highest per-person costs across the six countries at approximately £18,000 ($22,910).

Professor Iain Chapple, Professor of Periodontology and Consultant in Restorative Dentistry at the University of Birmingham and lead of the Oral, Intestinal and Systemic Health research theme at the National Institute for Health and Care Research (NIHR) Birmingham Biomedical Research Centre (BRC), commented:

“Our study highlights the critical need for early and sustained preventive measures to address the economic and health disparities associated with dental caries. By focusing on the most vulnerable populations, we can achieve substantial cost savings and improve overall oral health outcomes.

“In alignment with the recent World Health Organization’s Resolution on oral health, the results of our analysis support the case for a more inclusive public health approach to caries management, that incentivises and focuses on prevention rather than treatment to improve oral health in our populations.”

The study then analysed the potential healthcare cost reduction resulting from the implementation of various preventive measures, including both upstream and downstream interventions. These include societal-level initiatives like community water fluoridation, taxation on sugar-sweetened beverages, education programmes in schools, and oral health awareness campaigns; but also individual-level measures such as maintaining good oral hygiene by brushing with fluoridated toothpaste and applying topical fluoride.

If applied uniformly across the population, these interventions are estimated to reduce caries progression rates by 30%, with the greatest reduction in per-person costs for caries management seen in the most deprived group. A levelling-up approach to preventative measures, targeting those most in need, would have an even greater potential for cost savings, with reductions of approximately £14,000 ($17,728) per person in the UK in the most deprived group.

Professor Moritz Kebschull, head of the Division for Periodontology and Oral Rehabilitation at the University of Birmingham and researcher at the NIHR Birmingham BRC, said: “We observed that people in the most deprived groups have more dental caries from the start, which leads to more caries overall and higher costs. Therefore, it’s important to start preventive care early, focusing on reducing caries in young children and continuing throughout their lives.”

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Journal

BMC Public Health

DOI

10.1186/s12889-024-20652-0 

Article Title

Inequalities in oral health: estimating the longitudinal economic burden of dental caries by deprivation status in six countries

SPAGYRIC HERBALISM

The effect of long-term administration of green tea catechins on aging-related cardiac diastolic dysfunction and decline of troponin I

Compuscript Ltd

 

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Fig 1: Long-term EGCG intake alleviates aging-related cardiomyocyte apoptosis and mitochondrial damage. (A, B) Representative histology of heart tissue sections stained with hematoxylin-eosin stain and Masson's trichrome stain (yellow arrows collagen fibrosis; scale bar: 100 μm). (C) TUNEL stain for evaluation of cardiomyocyte apoptosis (red arrows apoptotic cells; 400 × ). (D) Transmission electron microscope (TEM) for the display of myocardial ultrastructure (blue arrows damaged mitochondria and orange arrows twisted myofilaments; 10000 × ). (E–G) Quantitative analysis of myocardial fibrosis, cardiomyocyte apoptosis, and mitochondrial destruction (n = 3–4). All results are represented as mean ± standard deviation. ∗∗∗P < 0.001.

 

 

 

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Credit: Genes & Diseases

A new publication from Genes & Diseases; DOI  10.1016/j.gendis.2024.101284, discusses the effect of long-term administration of green tea catechins on aging-related cardiac diastolic dysfunction and decline of troponin I.

 

Aging is an independent risk factor for cardiovascular diseases. Cardiac diastolic dysfunction (CDD), ultimately leading to heart failure with preserved ejection fraction (HFpEF), is prevalent among older individuals. Although therapeutics have made great progress, preventive strategies remain unmet medical needs.

 

Green tea catechins have been shown to be effective in improving aging-related cardiovascular and cerebral disorders in animal models and patients. However, little attention has been paid to whether long-term administration of epigallocatechin gallate (EGCG), the major bioactive ingredient of green tea catechins, could prevent the onset and progression of CDD.

 

In this study, 12-month-old female mice were orally administered 50, 100 and 200 mg EGCG mixed with drinking water for 6 months. Aged mice (18 months old) exhibited the major features of HFpEF, including CDD with pEF, cardiac fibrosis, increased cardiomyocyte apoptosis, and mitochondrial damages, as well as elevated A/B-type natriuretic peptide. Cardiac troponin I (cTnI) expression was also reduced. Long-term administration of 100 or 200 mg EGCG prevented aging-related CDD and exercise capacity decline, along with alleviating myocardial apoptosis and mitochondria damage. The transcription and protein expression of cTnI were increased, which might be achieved by inhibiting the expression and activity of histone deacetylase 1 (HDAC1), and reducing its binding level near cTnI's promoter, thereby elevating acetylated histone 3 (AcH3) and acetylated lysine 9 on histone H3 (AcH3K9) in the aged mice.

 

This article reports a novel insight that long-term administration of EGCG is a potentially effective strategy in preventing aging-related CDD and cTnI expression decline.

 

Keywords: Aging, Cardiac diastolic dysfunction, Cardiac troponin I, Epigallocatechin gallate, Histone deacetylase 1

 

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Junjun Quan, Zhongli Jia, Lingjuan Liu, Jie Tian, The effect of long-term administration of green tea catechins on aging-related cardiac diastolic dysfunction and decline of troponin I, Genes & Diseases, Volume 12, Issue 2, 2025, 101284, ISSN 2352-3042, https://doi.org/10.1016/j.gendis.2024.101284

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Journal

Genes & Diseases

DOI

10.1016/j.gendis.2024.101284 

 

Water and gruel – not bread: Discovering the diet of early Neolithic farmers in Scandinavia

At a 5,500-year-old Neolithic Danish settlement, archaeologists found grinding stones and early cereal grains. However, the stones weren't used to grind the grains for bread. Instead, the inhabitants likely prepared porridge or gruel from the cereals.

Aarhus University

 

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One of the 14 grindings tones that archeologists found while excavating a 5,500 years old settlement on the Danish island Funen. A new study reveals that the stones were not used to grind cereal grains.

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Credit: Niels H. Andersen, Moesgaard Museum

A grinding stone, as the name suggests, is a stone with a sufficiently flat surface that allows grinding against it with another, smaller stone.

Archaeologists found fourteen of such stones when they excavated the remains of a settlement from the Early Neolithic Funnel Beaker Culture at Frydenlund, on Strandby Mark southeast of Haarby on Funen (see fact box at the bottom of this text).

You can view 3D images of 11 different grindings stones from the Frydenlund site here (you can rotate and turn them with your mouse). 

They also found over 5,000 charred grain kernels of naked barley, emmer wheat, and durum wheat, amongst others.

One might offhand assume that the inhabitants 5,500 years ago ground their cereals into flour and baked bread with it. That has indeed been the typical interpretation of grinding stones from that time.

But they didn’t.

An international research team from Denmark, Germany and Spain has now analysed both the grains and the stones, concluding that the grinding stones were not used to grind cereals. 

The researchers examined microscopic mineral plant remains (phytoliths) and starch grains in small cavities on the surfaces of the stones. Surprisingly, they did not find any evidence of grinding of cereals.

The researchers found only few phytoliths on the stones, and the starch grains they identified came from wild plants instead of cereals.

“We have not identified the plants the starch grains originate from. We have merely ruled out the most obvious candidates – namely the cereals found at the settlement, which were not ground, as well as various collected species, including hazelnuts,” explains archaeobotanist, PhD Welmoed Out from Moesgaard Museum.

Together with senior researcher, Dr. Phil. Niels H. Andersen, also from Moesgaard Museum, she led the study recently published in the scientific journal Vegetation History and Archaeobotany.

What the grinding stones were used for remains open to interpretation, aside from the fact that they lack clear wear marks from the pushing motions used for grinding grain.

“The trough-shaped querns with traces of pushing movements emerged 500 years later. The grinding stones we studied here were struck with pestles made of stone, like crushing in a mortar. We also found such pestles at the site, resembling rounded, thick stone sausages. However, we have not analysed them for phytoliths or starch,” explains Niels H. Andersen.

This is the first time a state-of-the-art combination of phytolith and starch analyses has been performed on grinding stones from the first farmers in Northern Europe. The results support a hypothesis that archaeobotanists and archaeologists elsewhere in Northern Europe also have proposed after discovering remains of grains cooked into porridge and gruel: that the first farmers did not live on water and bread but rather on water and gruel, alongside berries, nuts, roots, and meat.
And yes, they likely drank water. According to Niels H. Andersen, no definitive traces of beer brewing have been found in Denmark before the Bronze Age.

However, as the two researchers from Moesgaard Museum emphasize: “This study only involves one settlement. While it supports other findings from the Funnel Beaker Culture, we cannot rule out the possibility of different results emerging when this method is applied to finds from other excavations.”

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Facts:

• The Funnel Beaker Culture was an early farming culture in Northern, Central, and Eastern Europe during the period ca. 4000–2800 BCE, marking the introduction of agriculture and cattle farming to Scandinavia. The name refers to the culture's commonly found clay beakers with funnel-shaped necks.
• The discovery on Southern Funen is the most extensive find of grinding stones and grains from the Funnel Beaker Culture in the entire region it encompassed.
• The study was done in collaboration between researchers from Moesgaard Museum and Aarhus University in Denmark, Kiel University in Germany and the Spanish National Research Council (IMF-CSIC) in Barcelona

Microscopies of four types of archaeological starch granules from different grinding stones from Frydenlund, magnified 400 times (the white bars represent 20 μm), each photographed in both plane-polarized (left) and cross-polarized light. The starch type shown in image a resembles starch from a grass subfamily of the Panicoideae type; the others are unidentified. Click to view the image in a larger format.

Credit

Cristina N. Patús, HUMANE, Barcelona.

Journal

Vegetation History and Archaeobotany

DOI

10.1007/s00334-024-01020-9 

Subject of Research

Not applicable

Article Title

Plant use at Funnel Beaker sites: combined macro- and microremains analysis at the Early Neolithic site of Frydenlund, Denmark (ca. 3600 bce)

Article Publication Date

16-Dec-2024

 

Growing safer spuds: removing toxins from potatoes

Using genetics to reduce food waste 

Peer-Reviewed Publication

University of California - Riverside

 

image: 

Adam Jozwiak, UC Riverside molecular biochemist in his laboratory.

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Credit: Adam Jozwiak/UCR

Scientists have discovered a way to remove toxic compounds from potatoes, making them safer to eat and easier to store. The breakthrough could cut food waste and enhance crop farming in space and other extreme environments.

Potato plants naturally produce chemicals that protect them from insects. The chemicals, called steroidal glycoalkaloids, or SGAs, are found in high quantities in the green parts of potato peels, and in the sprouting areas. They render the potatoes unsafe for insects as well as humans. 

"These compounds are critical for plants to ward off insects, but they make certain parts of these crops inedible," said Adam Jozwiak, a UCR molecular biochemist who led the study. "Now that we’ve uncovered the biosynthetic pathway, we can potentially create plants that produce these compounds only in the leaves while keeping the edible parts safe."

Sunlight can induce the production of SGAs in potato tubers — the part of the potato plant that is eaten — even after they’ve been harvested. By identifying a key genetic mechanism in SGA production, UC Riverside researchers may be able reduce potatoes’ toxicity while preserving the plants' natural defenses. Taking SGA out of potatoes will also make them easier to store and transport in open air.

The research, published in Science, focuses on a protein dubbed "GAME15," which plays a key role in directing the plant's production of SGAs. This protein acts both as an enzyme and a scaffold, organizing other enzymes into a "conversion factory" that efficiently produce SGAs while preventing toxic compounds from leaking into other parts of plant cells, where they would wreak havoc. 

Tomatoes also produce SGAs, primarily in the green, unripe fruit, as well as in the leaves, stems, and roots of the plants. When the researchers silenced the GAME15 gene in tomatoes, they eliminated SGA production but also made the plants highly susceptible to pests.

By engineering plants to control when and where SGAs are produced, for example, in the leaves but not the potatoes themselves, the researchers envision crops that can be stored without the risk of toxicity from sunlight exposure. 

"You could store the potatoes in your kitchen and not worry about exposure to sun, which makes them produce more SGAs. And then you could eat them whenever you want, reducing food waste,” Jozwiak said.

Additionally, the findings could enable the use of other plant parts, such as leaves, for food in limited-space environments like space missions or vertical farming systems. "For space farming, where every part of a plant may need to be edible, these findings are especially promising,” Jozwiak said.

The team achieved these insights by initially recreating the SGA production process in tobacco plants. Surprisingly, they found that during evolution the process redirected protein from the plasma membrane or Golgi apparatus, where it is responsible for the production of cell wall components crucial for cell growth, to the endoplasmic reticulum, a part of the cell where toxin production begins. 

“Essentially, the plant borrows from itself to create GAME15,” Jozwiak said. “We did not expect to find the plant hijacking protein it needs for the production of cell walls.”

Green, unripe fruit may be toxic, but during ripening these molecules convert to something edible. By limiting SGAs to non-edible parts of plants, farmers and consumers alike could benefit from safer, more versatile crops.

"Our work demonstrates that plants have evolved ingenious ways to balance growth, reproduction, and defense," Jozwiak said. "Understanding these systems allows us to redesign crops to meet modern needs without compromising their ability to thrive."

This research was a highly collaborative effort involving researchers from the Weizmann Institute of Science in Israel, as well as Kobe University, the RIKEN Center for Sustainable Resource Science, and Osaka University in Japan. The group’s findings not only hold the promise of healthier food but also represent a leap forward in sustainable agriculture and space exploration.

"We’re thrilled about the potential of this discovery," Jozwiak said. " It’s exciting to think about how we can now significantly extend the shelf life of crops like potatoes and reduce food waste on Earth and beyond.”

  

Potato and tomato in an experimental environment.

Credit

Adam Jozwiak/UCR

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Journal

Science

DOI

10.1126/science.adq5721 

Article Title

A cellulose synthase–like protein governs the biosynthesis of Solanum alkaloids

Article Publication Date

20-Dec-2024