. Scientific Frontline

Monday, November 21, 2022

Genetic ‘Hitchhikers’ Can Be Directed Using CRISPR

NC State researchers expand the CRISPR toolbox with possible agricultural implications.
Photo Credit: Atlas Green

In a new study, North Carolina State University researchers characterize a range of molecular tools to rewrite – not just edit – large chunks of an organism’s DNA, based on CRISPR-Cas systems associated with selfish genetic “hitchhikers” called transposons.

The researchers investigate diverse Type I-F CRISPR-Cas systems and engineer them to add genetic cargo – up to 10,000 additional genetic code letters – to the transposon’s cargo to make desired changes to a bacterium – in this case, E. coli.

The findings expand the CRISPR toolbox and could have significant implications in the manipulation of bacteria and other organisms at a time of need for flexible genome editing in therapeutics, biotechnology and more sustainable and efficient agriculture.

Bacteria use CRISPR-Cas as adaptive immune systems to withstand attacks from enemies like viruses. These systems have been adapted by scientists to remove or cut and replace specific genetic code sequences in a variety of organisms. The new finding shows that exponentially larger amounts of genetic code can be moved or added, potentially increasing CRISPR’s functionality.

Monitoring “frothy” magma gases could help evade disaster

Aerial photograph of Kusatsu-Shirane area (October 2021). Thanks to its geothermally active location, the town of Kusatsu, Gunma Prefecture (in the background of this image), is one of Japan’s most popular onsen (hot springs) destinations. The acidic and vibrant turquoise Yugama crater lake, however, is definitely not suitable for swimming.
Photo Credit: Tomoya Obase

Volcanic eruptions are dangerous and difficult to predict. A team at the University of Tokyo has found that the ratio of atoms in specific gases released from volcanic fumaroles (gaps in the Earth’s surface) can provide an indicator of what is happening to the magma deep below — similar to taking a blood test to check your health. This can indicate when things might be “heating up.” Specifically, changes in the ratio of argon-40 and helium-3 can indicate how frothy the magma is, which signals the risk of different types of eruption. Understanding which ratios of which gases indicate a certain type of magma activity is a big step. Next, the team hopes to develop portable equipment which can provide on-site, real-time measurements for a 24/7 volcanic activity monitoring and early warning system.

Does the thought of standing on a volcano make you quiver with excitement, or fear? For many people, living in the shadow of a volcano is part of daily life. Japan has 111 active volcanoes and an average of 15 volcanic “events,” including eruptions, every year. But these events are notoriously difficult to predict and can be deadly. In 2014, Mount Ontake, Japan’s second-highest volcano and a famous tourist spot, unexpectedly erupted, sadly killing 58 people and leaving five missing. Earthquake activity is typically an early warning sign, but some eruptions (including the one at Ontake) can occur without clear earthquake signals and so disaster mitigators, like the Japan Meteorological Agency, would benefit from other reliable ways to forewarn residents of the next potential disaster.

Intestinal microorganisms influence white blood cell levels in blood

Under normal conditions (steady state) neutrophils regulate the gut microbiota. When the number of neutrophils drops (neutropenia), the composition of the gut microbiota changes, stimulating T cells to produce IL-17A. IL-17-A in turn stimulates the production of neutrophils in the bone marrow (reactive granulopoiesis).
Illustration Credit: Daigo Hashimoto

White blood cells, or granulocytes, are cells that are part of the innate immune system. The most common type of granulocyte is the neutrophil, a phagocyte that destroys microbes in the body. Low neutrophil counts in the blood is called neutropenia; this condition is commonly seen in cases of leukemia or following chemotherapy. It is known that neutropenia induces granulopoiesis, the process formation of granulocytes. However, the exact mechanisms by which neutropenia drives granulopoiesis are not fully understood.

A team of researchers led by Associate Professor Daigo Hashimoto and Professor Takanori Teshima at Hokkaido University’s Faculty of Medicine have discovered that the gut microbiome plays a critical role in driving granulopoiesis in mice models. Their findings were published in the journal Proceedings of the National Academy of Sciences.

1,700-year-old spider monkey remains discovered in Teotihuacán, Mexico

Complete skeletal remains of a 1,700 year-old female spider monkey found in Teotihuacán, Mexico.
 Photo Credit: courtesy of Nawa Sugiyama

The complete skeletal remains of a spider monkey — seen as an exotic curiosity in pre-Hispanic Mexico — grants researchers new evidence regarding social-political ties between two ancient powerhouses: Teotihuacán and Maya Indigenous rulers.

The discovery was made by Nawa Sugiyama, a UC Riverside anthropological archaeologist, and a team of archaeologists and anthropologists who since 2015 have been excavating at Plaza of Columns Complex, in Teotihuacán, Mexico. The remains of other animals were also discovered, as well as thousands of Maya-style mural fragments and over 14,000 ceramic sherds from a grand feast. These pieces are more than 1,700 years old.

The spider monkey is the earliest evidence of primate captivity, translocation, and gift diplomacy between Teotihuacán and the Maya. Details of the discovery will be published in the journal PNAS. "This finding allows researchers to piece evidence of high diplomacy interactions and debunks previous beliefs that Maya presence in Teotihuacán was restricted to migrant communities," said Sugiyama, who led the research.

Short gamma-ray bursts traced farther into distant universe

Credit: W. M. Keck Observatory/Adam Makarenko

A Northwestern University-led team of astronomers has developed the most extensive inventory to date of the galaxies where short gamma-ray bursts (SGRBs) originate.

Using several highly sensitive instruments and sophisticated galaxy modeling, the researchers pinpointed the galactic homes of 84 SGRBs and probed the characteristics of 69 of the identified host galaxies. Among their findings, they discovered that about 85% of the studied SGRBs come from young, actively star-forming galaxies.

The astronomers also found that more SGRBs occurred at earlier times, when the universe was much younger — and with greater distances from their host galaxies’ centers — than previously known. Surprisingly, several SGRBs were spotted far outside their host galaxies — as if they were “kicked out,” a finding that raises questions as to how they were able to travel so far away.

“This is the largest catalog of SGRB host galaxies to ever exist, so we expect it to be the gold standard for many years to come,” said Anya Nugent, a Northwestern graduate student who led the study focused on modeling host galaxies. “Building this catalog and finally having enough host galaxies to see patterns and draw significant conclusions is exactly what the field needed to push our understanding of these fantastic events and what happens to stars after they die.”

A possible game changer for next generation microelectronics

Magnetic fields created by skyrmions in two-dimensional sheet of material composed of iron, germanium and tellurium.
Image Credit: Argonne National Laboratory.

Magnets generate invisible fields that attract certain materials. A common example is fridge magnets. Far more important to our everyday lives, magnets also can store data in computers. Exploiting the direction of the magnetic field (say, up or down), microscopic bar magnets each can store one bit of memory as a zero or a one — the language of computers.

Scientists at the U.S. Department of Energy’s (DOE) Argonne National Laboratory wants to replace the bar magnets with tiny magnetic vortices. As tiny as billionths of a meter, these vortices are called skyrmions, which form in certain magnetic materials. They could one day usher in a new generation of microelectronics for memory storage in high performance computers.

“We estimate the skyrmion energy efficiency could be 100 to 1000 times better than current memory in the high-performance computers used in research.” — Arthur McCray, Northwestern University graduate student working in Argonne’s Materials Science Division

“The bar magnets in computer memory are like shoelaces tied with a single knot; it takes almost no energy to undo them,” said Arthur McCray, a Northwestern University graduate student working in Argonne’s Materials Science Division (MSD). And any bar magnets malfunctioning due to some disruption will affect the others.

New quantum tool developed in groundbreaking experimental achievement

SFLORG Stock Photo

For the first time in experimental history, researchers at the Institute for Quantum Computing (IQC) have created a device that generates twisted neutrons with well-defined orbital angular momentum. Previously considered an impossibility, this groundbreaking scientific accomplishment provides a brand-new avenue for researchers to study the development of next-generation quantum materials with applications ranging from quantum computing to identifying and solving new problems in fundamental physics.

“Neutrons are a powerful probe for the characterization of emerging quantum materials because they have several unique features,” said Dr. Dusan Sarenac, research associate with IQC and technical lead, Transformative Quantum Technologies at the University of Waterloo. “They have nanometer-sized wavelengths, electrical neutrality, and a relatively large mass. These features mean neutrons can pass through materials that X-rays and light cannot.”

While methods for the experimental production and analysis of orbital angular momentum in photons and electrons are well-studied, a device design using neutrons has never been demonstrated until now. Because of their distinct characteristics, the researchers had to construct new devices and create novel methods for working with neutrons.

Disease-Resistant Corals Can Help ‘Rescue’ Vulnerable Ones

UC Davis Assistant Professor Anya Brown dives in a coral reef in Little Cayman as part of a research study.
Photo Credit: Julie Meyer/University of Florida

Under the right living arrangement, disease-resistant corals can help “rescue” corals that are more vulnerable to disease, found a study from the University of California, Davis, that monitored a disease outbreak at a coral nursery in Little Cayman, Cayman Islands.

The study, published in the journal Scientific Reports, found that when people grow corals of the same genotype — or genetic makeup — together, those corals are more vulnerable to disease than corals that grow among a mixture of genotypes. The study further found that some vulnerable corals can be “rescued” by resistant genotypes.

“We saw that some corals were more resistant to disease just by being around other corals that were particularly resistant,” said lead author Anya Brown, an assistant professor at the UC Davis Bodega Marine Laboratory in the Department of Evolution and Ecology. “Proximity to these resistant genotypes helped buffer the susceptible corals from the effects of the disease.”

The findings provide further evidence that genetic diversity can help reduce disease transmission among corals, while also showing that it’s important to consider how corals are arranged in nurseries and reef restoration projects to prevent the spread of disease.

Lab discovery leads UAH researchers to a simple, cost-effective electricity generator

Dr. Moonhyung Jang, left, operates the generator to light an LED display as Dr. Gang Wang looks on in the Adaptive Structures Laboratory. 
Photo Credit: Michael Mercier | University of Alabama in Huntsville

A bit of laboratory serendipity led University of Alabama in Huntsville (UAH) researchers to a simple mechanical way to generate electricity to operate electronic devices, says a paper they have published in the journal ACS Omega.

Triboelectric nanogenerators use multiple layers of different materials to generate electricity when pressed. While testing a triboelectric nanogenerator in the Adaptive Structures Laboratory of Dr. Gang Wang at UAH, a part of the University of Alabama System, postdoctoral research assistant Dr. Moonhyung Jang observed something unusual.

“During a finger-tapping test performed by Dr. Jang, a Scotch tape was introduced on the top to prevent electric shock,” says Dr. Wang, an associate professor of mechanical and aerospace engineering and the project’s principal investigator.

“An unexpectedly high voltage was observed. After a careful investigation, we figured out that the tape layer is the reason to cause this,” Dr. Wang says. “This led to our invention that introduces tacky materials to improve the performance of triboelectric generators.”

Technique Prints Flexible Circuits on Curved Surfaces, From Contact Lenses to Latex Gloves

Photo Credit: Yuxuan Liu.

Researchers from North Carolina State University have demonstrated a new technique for directly printing electronic circuits onto curved and corrugated surfaces. The work paves the way for a variety of new soft electronic technologies, and researchers have used the technique to create prototype “smart” contact lenses, pressure-sensitive latex gloves, and transparent electrodes.

“There are many existing techniques for creating printed electronics using various materials, but limitations exist,” says Yong Zhu, corresponding author of a paper on the work. “One challenge is that existing techniques require the use of polymer binding agents in the ‘ink’ you use to print the circuits. This impairs the circuit’s conductivity, so you have to incorporate an additional step to remove those binding agents after printing.

“A second challenge is that these printing techniques typically require you to print on flat surfaces, but many applications require surfaces that aren’t flat,” says Zhu, who is the Andrew A. Adams Distinguished Professor of Mechanical and Aerospace Engineering at NC State.

“We’ve developed a technique that doesn’t require binding agents and that allows us to print on a variety of curvilinear surfaces,” says Yuxuan Liu, first author of the paper and a Ph.D. student at NC State. ‘It also allows us to print the circuits as grid structures with uniform thickness.”

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