Discovery: plants use “trojan horse” to fight mold invasions

Photo Credit: Gábor Adonyi

UC Riverside scientists have discovered a stealth molecular weapon that plants use to attack the cells of invading gray mold. 

If you’ve ever seen a fuzzy piece of fruit in your fridge, you’ve seen gray mold. It is an aggressive fungus that infects more than 1,400 different plant species: almost all fruits, vegetables, and many flowers. It is the second most damaging fungus for food crops in the world, causing billions in annual crop losses.

A new paper in the journal Cell Host & Microbe describes how plants send tiny, innocuous-seeming lipid “bubbles” filled with RNA across enemy lines, into the cells of the aggressive mold. Once inside, different types of RNA come out to suppress the infectious cells that sucked them in.

“Plants are not just sitting there doing nothing. They are trying to protect themselves from the mold, and now we have a better idea how they’re doing that,” said Hailing Jin, Microbiology & Plant Pathology Department professor at UCR and lead author of the new paper.

Previously, Jin’s team discovered that plants are using the bubbles, technically called extracellular vesicles, to send small RNA molecules able to silence genes that make the mold virulent. Now, the team has learned these bubbles can also contain messenger RNA, or mRNA, molecules that attack important cellular processes, including the functions of organelles in mold cells. 

Toxic chemicals found in oil spills and wildfire smoke detected in killer whales

Orcas (killer whales)
Photo Credit: Bart van Meele

Toxic chemicals produced from oil emissions and wildfire smoke have been found in muscle and liver samples from Southern Resident killer whales and Bigg’s killer whales.

A study published in Scientific Reports is the first to find polycyclic aromatic hydrocarbons (PAHs) in orcas off the coast of B.C., as well as in utero transfer of the chemicals from mother to fetus.

“Killer whales are iconic in the Pacific Northwest—important culturally, economically, ecologically and more. Because they are able to metabolically process PAHs, these are most likely recent exposures. Orcas are our canary in the coal mine for oceans, telling us how healthy our waters are,” said senior author Dr. Juan José Alava, principal investigator of the UBC Ocean Pollution Research Unit and adjunct professor at Simon Fraser University.

PAHs are a type of chemical found in coal, oil and gasoline which research suggests are carcinogenic, mutagenic, and have toxic effects on mammals. Their presence in the ocean comes from several sources, including oil spills, burning coal and forest fire smoke particles.

Researchers analyzed muscle and liver samples from six Bigg’s, or transient, killer whales and six Southern Resident killer whales (SRKWs) stranded in the northeastern Pacific Ocean between 2006 and 2018. They tested for 76 PAHs and found some in all samples, with half the PAHs appearing in at least 50 per cent of the samples. One compound, a PAH derivative called C3-phenanthrenes/anthracenes, accounted for 33 per cent of total contamination across all samples. These forms of PAHs, known as alkylated PAHs, are known to be more persistent, toxic, and to accumulate more in the bodies of organisms or animals than parental PAHs.

Enlarged Spaces in Infant Brains Linked to Higher Risk of Autism, Sleep Problems

Dea Garic, PhD, and Mark Shen, PhD, both in the UNC School of Medicine’s Department of Psychiatry, have found that enlarged perivascular spaces in the brains of babies, caused by an accumulation of excess cerebrospinal fluid, have a 2.2 times greater chance of developing autism later in life.
Photo Credit: Courtesy of University of North Carolina at Chapel Hill

Throughout the day and night, cerebrospinal fluid (CSF) pulses through small fluid-filled channels surrounding blood vessels in the brain, called perivascular spaces, to flush out neuroinflammation and other neurological waste. A disruption to this vital process can lead to neurological dysfunction, cognitive decline, or developmental delays.

For the first time, researchers Dea Garic, PhD, and Mark Shen, PhD, both at the UNC School of Medicine’s Department of Psychiatry, discovered that infants with abnormally enlarged perivascular spaces have a 2.2 times greater chance of developing autism compared to infants with the same genetic risk. Their research also indicated that enlarged perivascular spaces in infancy are associated with sleep problems seven to 10 years after diagnosis.

“These results suggest that perivascular spaces could serve as an early marker for autism,” said Garic, assistant professor of psychiatry and a member of the Carolina Institute for Developmental Disabilities (CIDD).

The researchers studied infants at increased likelihood for developing autism, because they had an older sibling with autism. They followed these infants from 6-24 months of age, before the age of autism diagnosis. Their study, published in JAMA Network Open, found that thirty percent of infants who later developed autism had enlarged perivascular spaces by 12 months. By 24 months of age, nearly half of the infants diagnosed with autism had enlarged perivascular spaces.

Molecular jackhammers’ ‘good vibrations’ eradicate cancer cells

Ciceron Ayala-Orozco is a research scientist in the Tour lab at Rice University, and lead author on the study.
Photo Credit: Jeff Fitlow/Rice University

The Beach Boys’ iconic hit single “Good Vibrations” takes on a whole new layer of meaning thanks to a recent discovery by Rice University scientists and collaborators, who have uncovered a way to destroy cancer cells by using the ability of some molecules to vibrate strongly when stimulated by light.

The researchers found that the atoms of a small dye molecule used for medical imaging can vibrate in unison ⎯ forming what is known as a plasmon ⎯ when stimulated by near-infrared light, causing the cell membrane of cancerous cells to rupture. According to the study published in Nature Chemistry, the method had a 99 percent efficiency against lab cultures of human melanoma cells, and half of the mice with melanoma tumors became cancer-free after treatment.

“It is a whole new generation of molecular machines that we call molecular jackhammers,” said Rice chemist James Tour, whose lab has previously used nanoscale compounds endowed with a light-activated paddlelike chain of atoms that spins continually in the same direction to drill through the outer membrane of infectious bacteria, cancer cells and treatment-resistant fungi.

Researchers Find They Can Stop Degradation of Promising Solar Cell Materials

An illustration of metal halide perovskites. They are a promising material for turning light into energy because they are highly efficient, but they also are unstable. Georgia Tech engineers showed in a new study that both water and oxygen are required for perovskites to degrade. The team stopped the transformation with a thin layer of another molecule that repelled water.
Image Credit: Courtesy of Juan-Pablo Correa-Baena

Georgia Tech materials engineers have unraveled the mechanism that causes degradation of a promising new material for solar cells — and they’ve been able to stop it using a thin layer of molecules that repels water.

Their findings are the first step in solving one of the key limitations of metal halide perovskites, which are already as efficient as the best silicon-based solar cells at capturing light and converting it into electricity. They reported their work in the Journal of the American Chemical Society.

“Perovskites have the potential of not only transforming how we produce solar energy, but also how we make semiconductors for other types of applications like LEDs or phototransistors. We can think about them for applications in quantum information technology, such as light emission for quantum communication,” said Juan-Pablo Correa-Baena, assistant professor in the School of Materials Science and Engineering and the study’s senior author. “These materials have impressive properties that are very promising.”

Genetic Diversity of Wild North American Grapes Mapped

Dario Cantù, a professor in the Department of Viticulture and Enology, in the grape orchard outside the Robert Mondavi Institute for Wine and Food Science.
Photo Credit: Jael Mackendorf/UC Davis

Wild North American grapes are now less of a mystery after an international team of researchers led by the University of California, Davis, decoded and catalogued the genetic diversity of nine species of this valuable wine crop.

The research, published in the journal Genome Biology, uncovers critical traits that could accelerate grape breeding efforts, particularly in tackling challenges like climate change, saline environments and drought.

“This research marks a significant step in understanding the genetics of grapevines,” said Dario Cantù, the senior author on the journal article and a professor in the Department of Viticulture and Enology. “It lays the groundwork for future advancements in grape breeding by identifying key genes responsible for important traits.”

The research team developed and used state-of-the-art technology to construct a comprehensive pangenome, which is a complete genetic blueprint, of wild grape species.

This so-called super-pangenome of nine species allowed the team to map genetic diversity, identify similarities or differences among them, and pinpoint specific traits that breeders may want to incorporate. First author Noé Cochetel, a postdoctoral researcher in Cantù’s lab, did the analyses and played a pivotal role in the project.

Scientists reveal superconductor with on-off switches

(A) The material used in this study consists of stacked layers of ferromagnetic atoms and superconducting atoms. (B) Applying a small magnetic field induces superconductivity, while (C) low temperatures boost that superconductivity.
Illustration Credit: Courtesy Shua Sanchez, University of Washington

As industrial computing needs grow, the size and energy consumption of the hardware needed to keep up with those needs grows as well. A possible solution to this dilemma could be found in superconducting materials, which can reduce that energy consumption exponentially. Imagine cooling a giant data center full of constantly running servers down to nearly absolute zero, enabling large-scale computation with incredible energy efficiency.

Physicists at the University of Washington and the U.S. Department of Energy’s (DOE) Argonne National Laboratory have made a discovery that could help enable this more efficient future. Researchers have found a superconducting material that is uniquely sensitive to outside stimuli, enabling the superconducting properties to be enhanced or suppressed at will. This enables new opportunities for energy-efficient switchable superconducting circuits. The paper was published in Science Advances.

Superconductivity is a quantum mechanical phase of matter in which an electrical current can flow through a material with zero resistance. This leads to perfect electronic transport efficiency. Superconductors are used in the most powerful electromagnets for advanced technologies such as magnetic resonance imaging, particle accelerators, fusion reactors and even levitating trains. Superconductors have also found uses in quantum computing.

A temporary tug-of-war: a minimal system unlocks cellular transport secrets

A visual representation of the findings. The net number of cargo-bound kinesin or dynein motor proteins engaging with the microtubule track decides whether it is moved in positive or negative direction. When both, kinesins and dyneins engage with the microtubule, the transport is often interrupted. Occasionally, the cargo is being pulled by motor proteins in opposite directions before one finally wins.
Illustration Credit: Diez Lab

Cells are busy conglomerates. Different molecules and organelles have to be delivered to different locations at a specific time.  How exactly they are reaching their destinations is a long-standing question in biology. Researchers from the Diez group at the B CUBE – Center for Molecular Bioengineering of TUD Dresden University of Technology and the Santen group at the Center for Biophysics at the Saarland University have now built a minimal version of a cell transport system outside a cell. Using the minimal system, the team discovered the principles of how cells control the direction of transport. The new study was published in the journal Nature Communications.

Cells are like busy factories. They need to transport molecules and organelles (cargo) reliably to different destinations within the cell. Defects in cellular transport have been associated with many diseases including Alzheimer’s, Parkinson’s, and Huntington’s. The transport relies on a system of cellular train tracks known as microtubules. Two types of motor proteins, kinesin and dynein, can move in opposite directions along the microtubules to carry the cargo to its destination. At any given time, the cargo is attached to multiple copies of kinesin and dynein. Yet, it moves in only one direction. It is unclear what determines the moving direction.

When the Cellular Waste Collector Doesn’t Show Up

Verian Bader and Konstanze Winklhofer (right) are on the trail of the development of neurodegenerative diseases.
Photo Credit: © RUB, Marquard

Researchers have identified a mechanism that promotes the breakdown of harmful protein deposits. If it malfunctions, it can lead to Parkinson’s disease.

NEMO, a protein that is primarily associated with signaling processes in the immune system, prevents the deposition of protein aggregates that occur in Parkinson’s disease. For this purpose, it binds to certain protein chains that serve as markers for cellular waste removal, thus promoting the degradation of the harmful aggregates. A research team headed by Professor Konstanze Winklhofer from Ruhr University Bochum, Germany, has shed light on how this mechanism works. The team published their findings in the journal Nature Communications on December 19, 2023. In follow-up studies, the team is investigating ways to harness the findings for therapeutic strategies.

Looking for targeted therapeutic approaches

Neurodegenerative diseases, such as Parkinson’s or Alzheimer’s disease, are associated with the deposition of protein aggregates in the brain. These aggregates accumulate when the cellular waste removal system is defective or overloaded. In Parkinson’s disease, aggregates consisting primarily of the protein ⍺-synuclein are found in certain regions of the brain. “The fact that such aggregates occur, which are referred to as Lewy bodies, is a key feature of Parkinson’s disease,” explains Konstanze Winklhofer.

The misfolding and aggregation of ⍺-synuclein is of crucial importance for processes that lead to the loss of function and death of neuronal cells and contribute to the progression of the disease. Researchers from various disciplines around the world are therefore aiming to decipher these processes at a cellular and molecular level, in order to develop targeted therapeutic approaches.

Coral atoll islands may outpace sea-level rise

Atoll Coastline
Photo Credit: xiSerge

Ecological restoration may save coral atoll islands from the rising seas of climate change, according to an international team of scientists, conservationists, and an indigenous leader.

While global carbon emission reduction is imperative, local measures could be the key to the islands outpacing sea levels, they argue in the journal Trends in Ecology & Evolution.

“Far from being doomed, in their natural state most coral atoll islands could adapt to sea level rise,” says Dr Sebastian Steibl from Waipapa Taumata Rau, University of Auckland, lead author of the study. “This paper is a global call to identify and quantify the best measures for restoring atoll island growth.”

The world’s 320 tropical coral atolls are made up of thousands of islands and are a treasure trove of biodiversity, homes to millions of turtles and seabirds. These islands are naturally growing up to 1 cm a year by accreting sediment – enough to outpace most predictions of sea level rise.

Ecologically restoring this natural process holds the key to climate change resilience for the islands, says the team of scientists, who are already trialing restoration methods on atolls such as Tetiaroa and Palmyra in the eastern Pacific Ocean and Aldabra in the western Indian Ocean.

Can we decode the language of our primate cousins?

The UNIGE team wanted to find out whether the frontal and orbitofrontal regions of our brain activate in the same way when faced with human and simian vocalizations.
Image Credit: © Leonardo Ceravolo

Are we able to differentiate between the vocal emissions of certain primates? A team from the University of Geneva (UNIGE) asked volunteers to categorize the vocalizations of three species of great apes (Hominidae) and humans. During each exposure to these "onomatopoeia", brain activity was measured. Unlike previous studies, the scientists reveal that phylogenetic proximity - or kinship - is not the only factor influencing our ability to identify these sounds. Acoustic proximity - the type of frequencies emitted - is also a determining factor. These results show how the human brain has evolved to process the vocal emissions of some of our closest cousins more efficiently. Find out more in the journal Cerebral Cortex Communications.

Our ability to process verbal language is not based solely on semantics, i.e. the meaning and combination of linguistic units. Other parameters come into play, such as prosody, which includes pauses, accentuation and intonation. Affective bursts - "Aaaah!" or ‘‘Oh!’’ for example - are also part of this, and we share these with our primate cousins. They contribute to the meaning and understanding of our vocal communications.

When such a vocal message is emitted, these sounds are processed by the frontal and orbitofrontal regions of our brain. The function of these two areas is, among other things, to integrate sensory and contextual information leading to a decision. Are they activated in the same way when we are exposed to the emotional vocalizations of our close cousins, the chimpanzees, macaques and bonobos? Are we able to differentiate between them?

Researchers invent "Methane Cleaner": could become a permanent fixture in cattle and pig barns

A look inside the MEPS reactor (Methane Eradication Photochemical System), where chlorine atoms are formed by UV light and react with methane gas.
Photo Credit: Morten Krogsbøll.

In a spectacular new study, researchers from the University of Copenhagen have used light and chlorine to eradicate low-concentration methane from air. The result gets us closer to being able to remove greenhouse gases from livestock housing, biogas production plants and wastewater treatment plants to benefit the climate. The research has just been published in the journal Environmental Research Letters. 

The Intergovernmental Panel on Climate Change (IPCC) has determined that reducing methane gas emissions will immediately reduce the rise in global temperatures. The gas is up to 85 times more potent of a greenhouse gas than CO2, and more than half of it is emitted by human sources, with cattle and fossil fuel production accounting for the largest share.

A unique new method developed by a research team at the University of Copenhagen’s Department of Chemistry and spin-out company Ambient Carbon has succeeded in removing methane from the air.

"A large part of our methane emissions comes from millions of low-concentration point sources like cattle and pig barns. In practice, methane from these sources has been impossible to concentrate into higher levels or remove. But our new result proves that it is possible using the reaction chamber that we’ve have built," says Matthew Stanley Johnson, the UCPH atmospheric chemistry professor who led the study.

Earlier, Johnson presented the research results at COP 28 in Dubai via an online connection and in Washington D.C. at the National Academy of Sciences, which advises the US government on science and technology.

Some coral species might be more resilient to climate change than previously thought

OSU coral researcher Alex Vompe off the north shore of Mo'orea
Photo Credit: Mackenzie Kawahara

Some coral species can be resilient to marine heat waves by “remembering” how they lived through previous ones, research by Oregon State University scientists suggests.

The study also contains evidence that the ecological memory response is likely linked to the microbial communities that dwell among the corals.

The findings, published today in Global Change Biology, are important because coral reefs, crucial to the functioning of planet Earth, are in decline from a range of human pressures including climate change, said the study’s lead author, Alex Vompe.

“It is vital to understand how quickly reefs can adapt to ever more frequent, repeated disturbances such as marine heat waves,” said Vompe, a doctoral student who works in the lab of microbiology professor Rebecca Vega Thurber. “The microbiomes living within their coral hosts might be a key component of rapid adaptation.”

Heat waves are likely to increase in frequency and severity because of climate change, he added. Slowing down the rate of coral cover and species loss is a major conservation goal, and predicting and engineering heat tolerance are two important tools.

Giant bacterium powers itself with unique processes

Micrograph of a group of Epulopiscium viviparus bacteria.
Image Credit: Esther Angert

Not all bacteria are created equal.

Most are single-celled and tiny, a few ten-thousandths of a centimeter long. But bacteria of the Epulopiscium family are large enough to be seen with the naked eye and 1 million times the volume of their better-known cousins, E. coli.

In a study published Dec. 18 in Proceedings of the National Academy of Sciences, researchers from Cornell and Lawrence Berkeley National Laboratory have for the first time described the full genome of one species of the family of giants, which they’ve named Epulopiscium viviparus.

“This incredible giant bacterium is unique and interesting in so many ways: its enormous size, its mode of reproduction, the methods by which it meets its metabolic needs and more,” said Esther Angert, professor of microbiology in the College of Agriculture and Life Sciences, and corresponding author of the study. “Revealing the genomic potential of this organism just kind of blew our minds.”

The first member of the Epulopiscium family was discovered in 1985. All members of the species live symbiotically within the intestinal tracts of certain surgeonfish in tropical marine coral reef environments, such as the Great Barrier Reef and in the Red Sea.

Recent volcanism on Mars reveals a planet more active than previously thought

This image taken by the European Space Agency's Mars Express orbiter shows an oblique view focusing on one of the vast lava flows in Elysium Planitia.
Image Credit: ESA/DLR/FU Berlin

A vast, flat, "featureless" plain on Mars surprised researchers by revealing a much more tumultuous geologic past than expected, according to a study led by researchers at the University of Arizona. Enormous amounts of lava have erupted from numerous fissures as recently as one million years ago, blanketing an area almost as large as Alaska and interacting with water in and under the surface, resulting in large flood events that carved out deep channels.

Lacking plate tectonics – shifting chunks of crust that constantly reshape Earth's surface – Mars has long been thought to be a geologically "dead" planet where not much is happening. Recent discoveries have researchers questioning this notion, however. Just last year, a team of planetary scientists, also at UArizona, presented evidence for a giant mantle plume underneath the region Elysium Planitia, driving intense volcanic and seismic activity in a relatively recent past.

In the most recent study, a team led by Joana Voigt and Christopher Hamilton at UArizona's Lunar and Planetary Laboratory combined spacecraft images and measurements from ground-penetrating radar to reconstruct in three-dimensional detail every individual lava flow in Elysium Planitia. The extensive survey revealed and documented more than 40 volcanic events, with one of the largest flows infilling a valley named Athabasca Valles with almost 1,000 cubic miles of basalt.