Thursday, September 07, 2023

Exclusive-Biden administration moving to escalate energy trade dispute with Mexico


1st anniversary of entry-into-force of the United States-Mexico-Canada Agreement


By Jarrett Renshaw and David Lawder
Wed, September 6, 2023 

(Reuters) - President Joe Biden's administration has asked U.S. energy companies to prepare affidavits documenting how Mexico’s protectionist policies disrupted their investments as Washington prepares to escalate a trade dispute with its neighbor, according to three people familiar with the discussions.

The request for affidavits from major U.S. oil and renewable energy companies represents the latest and clearest signal that the Office of the United States Trade Representative (USTR) plans to seek an independent dispute settlement panel under the United States Mexico Canada Agreement trade pact, or USMCA.

Mexico President Andres Manuel Lopez Obrador's steps to roll back reforms aimed at opening Mexico's power and oil markets to foreign competitors ultimately sparked the trade dispute.

U.S. energy and power companies, such as Chevron and Marathon Petroleum, which sought to expand in Mexico, have complained that they have been denied simple permits and applications in decisions that favored state oil company Petroleos Mexicanos (Pemex) and national power utility Comision Federal de Electricidad (CFE).

The United States is likely to seek a dispute panel before the end of the year if talks on the issue continue to stall, and the affidavits represent evidence that would be included in the panel request, the sources said. If that panel rules against Mexico and it fails to take corrective action, Washington could ultimately impose billions of dollars in retaliatory tariffs on Mexican goods.

The people asked not to be named because they are not authorized to speak publicly on the matter.

The steps add to a significant worsening of trade relations between Washington and Mexico City, even as their economic integration grows. In August, USTR requested a USMCA dispute settlement panel to intervene in a disagreement over Mexico's curbs on genetically modified corn imports. Mexico now buys about $5 billion worth of U.S. GM corn annually, mostly for livestock feed.

Like the energy policies, Washington argues that banning GMO corn for human and animal consumption violates Mexico's obligations under the trade pact.

Obrador is seen as a major obstacle to resolving both disputes since he sees energy and corn as important to Mexico’s national identity.

A USTR spokesperson declined to comment.

Mexico’s Economy Ministry, in response to a Reuters request for comment, said it had no information regarding the matter.

The White House has hoped to avoid escalating energy trade tensions with Mexico as it sought help on immigration and drug trafficking, but talks that began last year have made little progress. Raising the stakes in the dispute carries significant risk for Biden, who will face Republican criticism over his handling of immigration and drug trafficking as he seeks reelection in 2024.

Mexico overtook Canada and China to become the largest U.S. goods trading partner in the first half of 2023, reaching total trade of $396.6 billion for the period as Mexico's automotive production grows and other U.S. companies shift supply chains from China closer to home.

In 2022, Mexico had a $130.5 billion goods trade surplus with the United States. It is on track to more than double from the $69 billion surplus in 2017, when former President Donald Trump launched a renegotiation of NAFTA after threatening to quit the pact, claiming it was draining U.S. manufacturing jobs.

DISPUTE PANEL

By seeking a dispute settlement panel, USTR would be essentially giving up negotiations, turning instead to a form of litigation created in the 2020 revamp of the former North American Free Trade Agreement.

Under USMCA's dispute settlement rules, a five-person panel, chosen from a roster of pre-approved experts, must be convened within 30 days, with a chair jointly chosen and the U.S. side choosing two Mexican panelists and Mexico choosing two American panelists. The panel will review testimony and written submissions and its initial report is due 150 days after the panel is convened.

Last year, one such panel ruled in Washington's favor in a dispute over Canadian dairy quotas, and against the U.S. on automotive rules of origin, siding with Mexico and Canada.

(Reporting By Jarrett Renshaw and David Lawder; additional reporting by Stephen Eisenhammer from Mexico; Editing by Tomasz Janowski)

 

Does cyberbullying affect adolescents’ risk of developing eating disorders?


Peer-Reviewed Publication

WILEY





In a study of US adolescents, both victims and perpetrators of cyberbullying were more likely than other youth to experience eating disorder symptoms. The findings are published in the International Journal of Eating Disorders.

In the study of 10,258 adolescents aged 10–14 years, participants answered questions about whether they had experienced cyberbullying victimization and perpetration, as well as whether they had experienced eating disorder symptoms.

Cyberbullying victimization was associated with worrying about weight gain, tying self-worth to weight, inappropriate compensatory behaviors to prevent weight gain, binge eating, and distress with binge eating.

Cyberbullying perpetration was associated with worrying about weight gain, tying self-worth to weight, and distress with binge eating.

“Adolescents experience cyberbullying related to appearance and weight. Cyberbullying can lead to low self-esteem, body dissatisfaction, and the development of an eating disorder,” said senior author, Jason M. Nagata MD, of the University of California, San Francisco. “Adolescents should limit social media that encourages eating disorders and appearance comparisons. Parents should advise their children to avoid cyberbullying and encourage them to report online harassment if it occurs.”

URL upon publication: https://onlinelibrary.wiley.com/doi/10.1002/eat.24034

 

Additional Information
NOTE: 
The information contained in this release is protected by copyright. Please include journal attribution in all coverage. For more information or to obtain a PDF of any study, please contact: Sara Henning-Stout, newsroom@wiley.com.

About the Journal
With a mission to advance the scientific knowledge needed for understanding, treating, and preventing eating disorders, the International Journal of Eating Disorders publishes rigorously evaluated, high-quality contributions to an international readership of health professionals, clinicians and scientists.

About Wiley
Wiley is a knowledge company and a global leader in research, publishing, and knowledge solutions. Dedicated to the creation and application of knowledge, Wiley serves the world’s researchers, learners, innovators, and leaders, helping them achieve their goals and solve the world's most important challenges. For more than two centuries, Wiley has been delivering on its timeless mission to unlock human potential. Visit us at Wiley.com. Follow us on FacebookTwitterLinkedIn and Instagram.

 

Are children’s growing pains tied to migraines?


Peer-Reviewed Publication

WILEY





New research published in Headache reveals that, in children and adolescents, pain in the lower limbs—what are often called “growing pains” by clinicians and are commonly attributed to rapid growth—may indicate the presence or risk of migraines.

The study included 100 children and adolescents born to mothers with migraines seen at a headache clinic, with half of the youth experiencing growing pains.

“In families of children with growing pains, there is an increased prevalence of other pain syndromes, especially migraine among parents,” the authors wrote. “On the other hand, children with migraine have a higher prevalence of growing pains, suggesting a common pathogenesis; therefore, we hypothesized that growing pains in children are a precursor or comorbidity with migraine.”

After 5 years of follow-up, 78 patients completed the study, of which 42 were from the group that experienced growing pains and 36 were from the control group. Headaches occurred in 76% of participants who had growing pains and in 22% of controls. Growing pains persisted in 14% of participants who had growing pains at the start of the study and appeared in 39% of participants who were previously asymptomatic.

“Pain in the lower limbs of children and adolescents... may reflect a precursor or comorbidity with migraine,” the authors concluded.

URL upon publication: https://onlinelibrary.wiley.com/doi/10.1111/head.14608

 

Additional Information
NOTE: 
The information contained in this release is protected by copyright. Please include journal attribution in all coverage. For more information or to obtain a PDF of any study, please contact: Sara Henning-Stout, newsroom@wiley.com.

About the Journal
Headache publishes original articles on all aspects of head and face pain including communications on clinical and basic research, diagnosis and management, epidemiology, genetics, and pathophysiology of primary and secondary headaches, cranial neuralgias, and pains referred to the head and face. Monthly issues feature case reports, short communications, review articles, letters to the editor, and news items regarding AHS plus medicolegal and socioeconomic aspects of head pain. This is the official journal of the American Headache Society.

About Wiley
Wiley is a knowledge company and a global leader in research, publishing, and knowledge solutions. Dedicated to the creation and application of knowledge, Wiley serves the world’s researchers, learners, innovators, and leaders, helping them achieve their goals and solve the world's most important challenges. For more than two centuries, Wiley has been delivering on its timeless mission to unlock human potential. Visit us at Wiley.com. Follow us on FacebookTwitterLinkedIn and Instagram.

 

Does "BPA-Free" mean "Safe"? BHPF represses YTHDF2 to induce tissue-specific cell deaths and consequent developmental abnormalities


Peer-Reviewed Publication

SCIENCE CHINA PRESS

Does "BPA-Free" Mean "Safe"? BHPF represses YTHDF2 to induce tissue-specific cell deaths and consequent developmental abnormalities 

IMAGE: BEHIND THE POSITIVE IMAGE OF "BPA-FREE" BEING SYNONYMOUS WITH "SAFE," A BPA SUBSTITUTE CALLED BHPF IS "DESTROYING" A VITAL CELLULAR PROTEIN, YTHDF2. view more 

CREDIT: © ARTWORK BY WANNING WEI.





This study is led by Dr. Chih-Hung Hsu (Institute of Genetics, Zhejiang University), Dr. Fudi Wang (Zhejiang University School of Medicine, and Hengyang Medical School, University of South China), and Dr. Peng-Fei Xu (Institute of Genetics, Zhejiang University). Bisphenol A (BPA) is widely used in a range of plastic products. In recent years, many studies have found that BPA has adverse effects on both ecosystems and human health, and has been banned by many countries for use in the maternal and child products, such as baby bottles and children's water cups. As a result, a variety of bisphenol analogues (BPs) have been introduced as alternatives to BPA in these products. However, the potential developmental toxicity of these alternatives, particularly the health risks during early development, remains largely unknown. m6A modification is the most abundant modification found in eukaryotic mRNAs and, like histone/DNA modifications, it quickly responds to environmental stimuli, subsequently affecting gene expression and cellular homeostasis. "We found that a common BPA substitute, BHPF, induced tissue-specific ferroptosis and apoptosis in an m6A dependent manner, leading to cardiac and vascular developmental defects, respectively. These findings not only reveal novel mechanisms of m6A/YTHDF2-mediated regulation of tissue-specific PCDs, but also provide a previously unappreciated mechanistic insight into BHPF-induced cardiovascular defects. " Hsu says.

Firstly, the researchers comprehensively examined the concentration levels of eight common BPA substitutes in the serum of 100 pregnant participants. The results showed that three BPA substitutes have been detected in the blood samples of pregnant participants. Among them, BHPF (with high detection rate, 14%) has been associated with cardiovascular developmental defects in zebrafish embryos and the offspring from BHPF-gavage mice. In addition, in the pregnant subjects with detectable BHPF levels, the participant with the highest BHPF-detected concentrations was found to have fetus with ventricular septal defect (VSD). Together, these findings suggest that the widely used BHPF poses potential health threats to the environment, animals, and humans, representing an urgent environmental health issue that requires attention.

Through in-depth exploration of the underlying mechanisms, researchers found that BHPF induced cardiovascular developmental defects through m6A/YTHDF2-mediated regulation of tissue-specific cell death. Mechanistically, BHPF-mediated downregulation of YTHDF2 reduced YTHDF2-facilitated translation of m6A-gch1 for cardiomyocyte ferroptosis, and decreased YTHDF2-mediated m6A-sting1 decay for caudal vein plexus (CVP) apoptosis. In other words, under BHPF stimulation, the same responsive protein YTHDF2 in different tissues regulates two entirely independent cell death pathways through its multiple m6A regulatory functions, leading to distinct phenotypes. "Therefore, m6A/YTHDF2 can be considered as a " bifurcation" for BHPF-induced tissue-specific ferroptosis and apoptosis, which deepens our understanding of m6A functions at the organismal level. " Hsu says.

Consequently, the discovery of these new mechanisms suggests possible ways to counteract the damage caused by BHPF. Researchers demonstrated that blocking ferroptosis and apoptosis pathways induced by BHPF-m6A-YTHDF2 axis could substantially rescue the defective phenotypes of heart failure and CVP damage. Notably, the preclinical trials show that sapropterin dihydrochloride (an orally active synthetic form of BH4, the major component of the clinically used drug, KUVAN®) can rescue heart failure in cardiomyocyte-specific Ythdf2 conditional knockout mice, suggesting a feasible therapeutic strategy for dealing with BHPF-induced cardiac defects.

In conclusion, "BPA-free" plastic products are generally considered by the public as a “high-quality” and “safety” indicator. However, this study shows that "BPA-free" does not necessarily equal "absolutely safe" and serves as a good warning for the public on how to properly understand and view "BPA-free" maternal and infant products.

YTHDF2-mediated regulations bifurcate BHPF-induced programmed cell deaths

https://doi.org/10.1093/nsr/nwad227

 

Empowering Europe against infectious diseases: innovative framework to tackle climate-driven health risks


Peer-Reviewed Publication

CMCC FOUNDATION - EURO-MEDITERRANEAN CENTER ON CLIMATE CHANGE




Climate change is one of several drivers of recurrent outbreaks and geographical range expansion of infectious diseases in Europe. The paper Decision-Support Tools to Build Climate Resilience Against Emerging Infectious Diseases in Europe and Beyond“, published on The Lancet Regional Health – Europe journalintroduces a transformative approach to tackle the emergence and transmission of climate-sensitive infectious diseases in Europe, informing cross-sectoral policy while improving the long-term climate resilience of health systems to infectious disease risks.

The paper is authored by a distinguished team of international researchers as part of their work in IDAlert, the international project with contribution of CMCC will help build a Europe more resilient to emerging health threats. CMCC@Ca’Foscari researchers Shouro DasguptaKatie Johnson, and Francesco Bosello contributed to socio-economic inequality, adaptation strategies, and stakeholders involvement aspects of the paper, which proposes a collaborative approach to develop policy-relevant indicators and decision-support tools. These tools are designed to comprehensively track and anticipate climate-induced disease risks across various domains, including environmental hazard, exposure patterns, and vulnerability factors. With a keen focus on the interconnectedness of animals, humans, and the environment, the framework promises a holistic perspective to address this multifaceted challenge.

The lead author and IDAlert project coordinator Joacim Rocklöv highlighted, “Our decision-support tools offer a multi-dimensional perspective that transcends traditional silos. By examining the nexus of animals, humans, and the environment, we’re unlocking a more comprehensive understanding of disease dynamics a prerequisite for more timely and effective outbreak preparedness.”

The heart of this novel framework lies in the co-production of early warning and response systems with stakeholders and end-users, as well as tailored tools to assess the costs and benefits associated with climate adaptation and mitigation strategies across diverse sectors. By fostering greater resilience within regional and local health systems, the framework aims to strengthen Europe’s capacity to respond to health crises, even in the face of changing environmental conditions.

As part of its approach, the IDAlert project will integrate multi-level engagement, innovative methodologies, and novel data streams, and tap into locally generated intelligence and empirical insights through case studies. This strategy empowers experts to quantify the effects of climate-induced disease threats in areas undergoing rapid urban transformation and contending with heterogeneous health risks. The ultimate aspiration is to bridge the gap between knowledge and action, delivering an unparalleled integrated One Health—Climate Risk framework that will empower policymakers, healthcare professionals, and communities to mitigate risks and bolster resilience.

 

About The Lancet Regional Health – Europe Journal:

The Lancet Regional Health – Europe Journal is a prestigious journal renowned for publishing groundbreaking research on health challenges worldwide. It aims to promote the advancement of the research agenda, clinical practice and health policy in Europe with the goal of improving health outcomes for all people regionally and globally.

 

About the IDAlert project:

IDAlert – Infectious Disease decision-support tools and Alert systems to build climate Resilience to emerging health Threats  officially started on 1 June 2022 is a € 9.18 million project and lasts for five years. The project is funded by the European Commission under the Horizon Europe programme with Grant Agreement number 101057554.

More information: www.idalertproject.eu

 

The full paper, “Decision-Support Tools to Build Climate Resilience Against Emerging Infectious Diseases in Europe and Beyond,” is available on the Lancet Regional Health Journal website: https://www.thelancet.com/journals/lanepe/article/PIIS2666-7762(23)00120-5/fulltext

 

Researchers develop highly efficient and stable photoelectrode for water splitting using organic semiconductors


Their findings have been selected for the supplementary cover of ACS Energy Letters and published on June 9, 2023

Peer-Reviewed Publication

ULSAN NATIONAL INSTITUTE OF SCIENCE AND TECHNOLOGY(UNIST)

Professor Ji-Hyun Jang and her research team 

IMAGE: PROFESSOR JI-HYUN JANG (SECOND FROM LEFT) FROM THE SCHOOL OF ENERGY AND CHEMICAL ENGINEERING AT UNIST view more 

CREDIT: UNIST




A team of researchers, led by Professor Ji-Hyun Jang from the School of Energy and Chemical Engineering at UNIST has achieved a significant breakthrough in photoelectrode development. Through collaborative research with Professor Junghoon Lee from Dongseo University and Dr. Hyo-Jin Ahn from the German Engineering Research and Development Center LSTME Busan , the team successfully created a high-performance and stable photoelectrode by incorporating organic semiconductors as an intermediate layer in existing inorganic semiconductor-based photoelectrodes.

The production of green hydrogen using solar energy involves splitting water into its constituent elements through charges generated in semiconductors that absorb sunlight. Previous studies primarily focused on utilizing inorganic semiconductors for constructing photoelectrodes. However, organic semiconductors offer several advantages such as lower costs, various process methods, and easier large-scale production. Additionally, their high solar energy conversion efficiency translates to enhanced hydrogen production efficiency. Nevertheless, the susceptibility of organic semiconductors to water damage has limited their application in photoelectrodes.

To overcome this challenge, the research team applied a coating of organic semiconductors onto the surface of conventional iron oxide-based photoelectrodes to ensure stability when exposed to water. Furthermore, they implemented a catalyst (nickel/iron double-layer hydroxide) as an additional protective layer over the coated organic semiconductor to prevent direct contact with water. This innovative approach allowed the charges generated from solar energy absorption to facilitate efficient hydrogen production reactions.

Professor Jang expressed the team’s excitement about the research outcomes, by saying, “By overcoming the limitations of traditional inorganic semiconductor-oriented photoelectrodes, we have demonstrated the potential for more extensive utilization of organic semiconductors in hydrogen production through photoelectrodes.”

This breakthrough not only opens up new possibilities for enhancing efficiency and stability but also contributes to advancing sustainable energy solutions for a carbon-neutral future.

The study findings have been published ahead of their official publication in the online version of ACS Energy Letters on March 12, 2023. This work was selected for the supplementary cover of the journal and was subsequently published on June 9, 2023. The main authors were Dr. Hyo-Jin Ahn (LSTME Busan) and Ki-Yong Yoon (UNIST). Funding support was provided by the National Research Foundation of Korea (NRF) and the Ministry of Science and ICT (MSIT).

Scheme for the fabrication of NiFe(OH)x/PSi/Ti–Fe2O3

CREDIT

UNIST

Journal Reference
Hyo-Jin Ahn, Ki-Yong Yoon, Mingi Sung, et al., “Utilizing a Siloxane-Modified Organic Semiconductor for Photoelectrochemical Water Splitting,” ACS Energy Lett., (2023).

 

Obesity-related cardiovascular disease deaths tripled between 1999 and 2020


Black adults had the highest rates of obesity-related cardiovascular disease deaths 1999 to 2020, with the highest percentage found in Black women, according to a new study in Journal of the American Heart Association


Peer-Reviewed Publication

AMERICAN HEART ASSOCIATION





Research Highlights:

  • Obesity-related cardiovascular disease deaths tripled between 1999 and 2020 in the U.S.
  • Such deaths were higher among Black individuals (highest among Black women) compared with any other racial group, followed by American Indian/Alaska Native people.
  • Black adults who lived in urban communities experienced more obesity-related cardiovascular disease deaths than those living in rural areas, whereas the reverse was true for all other racial groups.

This news release has been updated to include a quote from the senior author.

Embargoed until 4 a.m. CT/5 a.m. ET Wednesday, Sept. 6, 2023

DALLAS, Sept. 6, 2023 — There has been a recent three-fold increase in obesity-related deaths from heart disease in the U.S. between 1999 and 2020, according to new research published today in the Journal of the American Heart Association, an open access, peer-reviewed journal of the American Heart Association.

“The number of people with obesity is rising in every country across the world. Our study is the first to demonstrate that this increasing burden of obesity is translating into rising heart disease deaths,” said lead study author and cardiologist Zahra Raisi-Estabragh, M.D., a clinical lecturer at the William Harvey Research Institute in London. “This rising trend of obesity is affecting some populations more than others, particularly Black women.”

Obesity remains a global public health crisis and is a major risk factor for cardiovascular disease. It currently affects about 42% of the U.S. population, an increase by almost 10% from the preceding decade, according to the American Heart Association’s 2023 statistics.

Researchers analyzed race, gender and urban versus rural settings to determine differences in heart disease deaths in which obesity was listed as a contributing factor. Among the findings:

  • Overall, obesity-related cardiovascular disease deaths tripled from 2.2 per 100,000 population to 6.6 per 100,000 population between 1999 and 2020.
  • Obesity-related cardiovascular disease deaths were higher among Black individuals compared with any other racial group, at 6.7 per 100,000 population; followed by American Indian adults or Alaska Native adults at 3.8 per 100,000.
  • Black women had the highest rates of obesity-related heart disease deaths than all others in the study. In other racial groups, men experienced more obesity-related heart disease deaths than women.
  • Black adults living in urban areas had higher rates of obesity-related heart disease deaths compared with Black adults living in rural areas, (6.8 versus 5.9 per 100,000) whereas rural living was associated with higher rates of obesity-related heart deaths for people in all other racial groups.

“The trend of higher obesity-related cardiovascular death rates for Black women than men was striking and different from all other racial groups considered in our study,” said senior author Mamas A. Mamas, M.D., D.Phil. professor of Cardiovascular Medicine from Keele University in Keele, United Kingdom.

In addition, Raisi-Estabaugh noted that Black individuals living in urban communities may be impacted more by socio-economic deprivation and health inequalities than Black people living in rural areas, and that they did not benefit from increased access to health care that appears to benefit people of other racial groups who live in urban areas.

Study details and background:

  • Researchers analyzed data collected from 1999 to 2020 on 281,135 deaths in which obesity was recorded as a contributing factor in The Multiple Cause of Death database includes mortality and population counts from all U.S. counties.
  • Among the deaths, 43.6% were in women; 78.1% of the group were white adults; 19.8% were Black adults; 1.1% were Asian or Pacific Islander adults and 1% were American Indian adults or Alaskan Native adults.

The researchers note that coding and data entry errors may be a limitation of the findings since the source was electronic health records that could not be verified by researchers for accuracy.  However, the results still underscore the need to address obesity more effectively in individuals and communities.

Co-authors, their disclosures and study funding sources are listed in the manuscript.

Studies published in the American Heart Association’s scientific journals are peer-reviewed. The statements and conclusions in each manuscript are solely those of the study authors and do not necessarily reflect the Association’s policy or position. The Association makes no representation or guarantee as to their accuracy or reliability. The Association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific Association programs and events. The Association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and biotech companies, device manufacturers and health insurance providers and the Association’s overall financial information are available here.

Additional Resources:

About the American Heart Association

The American Heart Association is a relentless force for a world of longer, healthier lives. We are dedicated to ensuring equitable health in all communities. Through collaboration with numerous organizations, and powered by millions of volunteers, we fund innovative research, advocate for the public’s health and share lifesaving resources. The Dallas-based organization has been a leading source of health information for nearly a century. Connect with us on heart.orgFacebookX (formerly known as Twitter) or by calling 1-800-AHA-USA1.

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Switching from harmful to helpful fungi


Genetic cluster in root fungus found to be the “on/off” switch for disease-causing behavior


Peer-Reviewed Publication

UNIVERSITY OF TOKYO

The effect of Colletotrichum tofieldae (Ct) on roots. 

IMAGE: THESE IMAGES SHOW THE STARTLING EFFECT OF HARMFUL CT3 SIGNIFICANTLY LIMITING ROOT GROWTH, COMPARED WITH BENEFICIAL CT GREATLY INCREASING ROOT GROWTH OF THALE CRESS. view more 

CREDIT: 2023, K. HIRUMA




Mold and diseases caused by fungi can greatly impact the shelf life of fruit and vegetables. However, some fungi benefit their hosts by aiding plant survival. Colletotrichum tofieldiae (Ct) is a root mold which typically supports continued plant development even when the plant is starved of phosphorus, an important nutrient for photosynthesis and growth. Researchers studied a unique pathogenic strain of the fungi, called Ct3, which conversely inhibits plant growth. By comparing the beneficial and harmful strains Ct strains, they found that activation of a single fungal secondary metabolism gene cluster determined the negative impact of the fungus on the host plant. When the cluster was disrupted, either genetically or by a change in environment, the fungi’s behavior changed from inhibiting growth to promoting it. Understanding mechanisms like this could help us reduce food waste by harnessing the beneficial role fungi can have on food.

 

When your fresh strawberries go fuzzy with mold, or grapes turn gray and shrivel at the bottom of the fruit bowl, it’s always a bit disappointing and unpleasant. The culprit is typically a disease-causing fungus called Botrytis, which devastates food crops globally and is easily spread by wind and soil. However, there are many fungi which have a less destructive relationship with their host plants, even forming partnerships which can help the plant to thrive. Promoting the beneficial traits of fungi and suppressing undesirable outcomes (like moldy fruit) would greatly aid global food security and help reduce a huge amount of food waste.

“Plant-associated fungi show varied infection lifestyles ranging from mutualistic (beneficial) to pathogenic (harmful) depending on the host enviroment. However, the mechanisms by which these microbes transit along these different lifestyles remain poorly understood,” said Associate Professor Kei Hiruma from the Graduate School of Arts and Sciences at the University of Tokyo. “We analyzed genetic information from varied strains of a root fungus called Colletotrichum tofieldiae using comparative transcriptomic analysis, which enabled us to study differences in gene expression between each strain. Surprisingly, we found that a single fungal secondary metabolism gene cluster, called ABA-BOT, solely determines whether the fungus exhibits pathogenic or mutualistic traits toward the host plant.”

Colletotrichum tofieldae is a fungus which typically benefits plants when they suffer a phosphorus deficiency, helping them thrive despite the lack of this vital nutrient. It has even been shown to increase the growth and yield of economically important crops such as maize and tomatoes. In this study, the multi-institutional team used thale cress as the host plant and sourced six strains of Ct from different geographical locations to infect it with. Five strains significantly promoted plant growth, as expected, but a sixth — called Ct3 — was found to suppress nutrient uptake, inhibiting plant growth and leading to symptoms of disease. So, what caused this drastic change?

“We identified two key points: First, on the fungal side, that Ct3 activates the ABA-BOT biosynthesis gene cluster; and second, on the plant side, that Ct3 induces the host plant’s ABA signaling pathways, through which the fungus inhibits plant growth,” explained Hiruma. The researchers found that both pathogenic and mutualistic strains of Colletotrichum tofieldae contain the ABA-BOT gene cluster, but mutualistic strains did not express it, i.e., the genes were not activated. The discovery came as a surprise, as conventionally pathogens and mutualists were thought to have distinct characteristics, but these findings suggest that they are more intricately related.

When the gene cluster was disrupted, either at a genetic level or by changing the plant’s environment, the Ct3 was rendered nonpathogenic and even became beneficial to the host, promoting root growth. Although further study is needed, it appears that the ABA-BOT gene cluster may contribute to pathogenesis in diverse fungi beyond the Ct species. For example, it may be involved in the pathogenesis of the Botrytis which afflicts our household fruit and vegetables. “If we gain a comprehensive understanding of the regulatory mechanisms governing the fungal secondary metabolism gene cluster, we can devise a method to selectively suppress potential pathogenesis in otherwise beneficial fungi, optimizing their utilization in agriculture and harnessing the full potential of the microbial diversity naturally present in soil ecosystems,” said Hiruma.

 “I have come to realize that even pathogens can exhibit nonharmful characteristics during a significant portion of their life cycles. In fact, I am beginning to contemplate the possibility that what we traditionally refer to as pathogens may actually function as beneficial microbes under other conditions.”

####

Paper Title:

Kei Hiruma, Seishiro Aoki, Junya Takino, Takeshi Higa, Yuniar Devi Utami, Akito Shiina, Masanori Okamoto, Masami Nakamura,  Nanami Kawamura, Yoshihiro Ohmori, Ryohei Sugita, Keitaro Tanoi, Toyozo Sato, Hideaki Oikawa, Atsushi Minami, Wataru Iwasaki, Yusuke Saijo. "A fungal sesquiterpene biosynthesis gene cluster critical for mutualist-pathogen transition in Colletotrichum tofieldiae." Nature Communications. doi: 10.1038/s41467-023-40867-w

Funding

This research was supported in part by the JSPS KAKENHI Grant (16H06279, 18K14466, 18H04822, 19H05688, 20H02986, 21H05150, 22H02204 (A.M.)), the JST grant (JPMJPR16Q7, JPMJCR19S2, JPMJSC1702, JPMJFR200A) and The Uehara Memorial Foundation (A.M.).

Useful Links

Graduate School of Arts and Sciences: https://www.c.u-tokyo.ac.jp/eng_site/

Hiruma Kei Laboratory: https://park.itc.u-tokyo.ac.jp/hiruma/index.html

Research Contact:

Associate Professor Kei Hiruma

Department of Life Sciences

Graduate School of Arts and Sciences

The University of Tokyo

3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan                                     

Email: hiruma@g.ecc.u-tokyo.ac.jp

Tel.: +81-3-5454-6631

Press contact:
Mrs. Nicola Burghall
Public Relations Group, The University of Tokyo,
7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, Japan
press-releases.adm@gs.mail.u-tokyo.ac.jp

About the University of Tokyo
The University of Tokyo is Japan's leading university and one of the world's top research universities. The vast research output of some 6,000 researchers is published in the world's top journals across the arts and sciences. Our vibrant student body of around 15,000 undergraduate and 15,000 graduate students includes over 4,000 international students. Find out more at www.u-tokyo.ac.jp/en/ or follow us on Twitter at @UTokyo_News_en.