Tiny CRISPR tool could help shred viruses

Model of a minimal CRISPR-Cas13bt3 molecule generated with a cryo-electron microscope. The RNA to be recognized and cleaved is colored in light blue, while the scissor is formed by the magenta and cyan colored domains. The two loops for controlling the CRISPR-Cas13bt3 are shown in green and red.
 Illustration Credit: Courtesy of the Yang Gao lab/Rice University

Small and precise: These are the ideal characteristics for CRISPR systems, the Nobel-prize winning technology used to edit nucleic acids like RNA and DNA.

Rice University scientists have described in detail the three-dimensional structure of one of the smallest known CRISPR-Cas13 systems used to shred or modify RNA and employed their findings to further engineer the tool to improve its precision. According to a study published in Nature Communications, the molecule works differently than other proteins in the same family.

“There are different types of CRISPR systems, and the one our research was focused on for this study is called CRISPR-Cas13bt3,” said Yang Gao, an assistant professor of biosciences and Cancer Prevention and Research Institute of Texas Scholar who helped lead the study. “The unique thing about it is that it is very small. Usually, these types of molecules contain roughly 1200 amino acids, while this one only has about 700, so that’s already an advantage.”

Atlantic walrus more vulnerable than ever to Artic warming

Photo Credit: Rod Long

Past cycles of climate change, along with human exploitation, have led to only small and isolated stocks of Atlantic walrus remaining. The current population is at high risk of the same issues affecting them severely, according to a new study led by Lund University in Sweden.

Today, the last remaining stocks of Atlantic walrus are more at danger than ever, due to a combination of Arctic warming and a long history of devastating human exploitation. Rising global temperatures are significantly impacting Arctic marine ecosystems and their inhabitants. However, little is known about exactly how this combination of stress factors will impact Arctic species.

Now, researchers have examined how walrus coped with past cycles of climate change. Using breakthroughs in ancient genomics, the team was able to extract, sequence and interpret ancient genetic information contained in teeth and bone that survive well in the Arctic’s frozen archaeological sites. These DNA results were integrated with modern genetic samples, enabling them to reconstruct how the genetic diversity of Atlantic walrus had changed under earlier cycles of global warming.

Understanding bacterial motors may lead to more efficient nanomachine motors

The FliG protein in the "bacterial motor"
Illustration Credit: Atsushi Hijikata, Yohei Miyanoiri, Osaka University

A research group led by Professor Emeritus Michio Homma (he, him) and Professor Seiji Kojima (he, him) of the Graduate School of Science at Nagoya University, in collaboration with Osaka University and Nagahama Institute of Bio-Science and Technology, have made new insights into how locomotion occurs in bacteria. The group identified the FliG molecule in the flagellar layer, the ‘motor’ of bacteria, and revealed its role in the organism. These findings suggest ways in which future engineers could build nanomachines with full control over their movements. They published the study in iScience. 

As nanomachines become smaller, researchers are taking inspiration from microscopic organisms for ways to make them move and operate. In particular, the flagellar motor can rotate clockwise and counterclockwise at a speed of 20,000 rpm. If scaled up, it would be comparable to a Formula One engine with an energy conversion efficiency of almost 100% and the capacity to change its rotation direction instantly at high speeds. Should engineers be able to develop a device like a flagellar motor, it would radically increase the maneuverability and efficiency of nanomachines. 

Curtin study suggests rare echidna noises could be the ‘language of love’

Echidnas, sometimes known as spiny anteaters, are quill-covered monotremes (egg-laying mammals) belonging to the family Tachyglossidae
Photo Credit: Emmanuel Higgins

Curtin University researchers have captured rare recordings of echidnas cooing, grunting and making a range of other sounds, but only during the breeding season.

Lead author Dr Christine Cooper, from Curtin’s School of Molecular and Life Sciences, said there had been ongoing scientific debate around the ability of echidnas to vocalize as a way of communicating or if the sounds they make are simply sniffing noises related to breathing.

“We observed wild short-beaked echidnas at Dryandra National Park, near Narrogin, Western Australia, making cooing and grunting sounds, in addition to the wheezing and exhalation noises that the animals are known to make,” Dr Cooper said.

“Our team managed to capture some of these sounds with hand-held microphones as well as a camera and microphone left unattended at the entrance to a cave popular with echidnas.

Could RNA folding play a role in the origin of life?

New research in membaneless compartments that model protocells reveals that naturally occurring chemical modifications to RNA molecules help them fold better into functional structures. Image of the structures of tRNA molecules from protocells determined by high-throughput sequencing using tRNA structure-seq are overlaid on and image of the membraneless compartments made through liquid-liquid phase separation.
(CC BY-NC-ND 4.0)
Image Credit: Bevilacqua and Keating Labs / Penn State.

New research in model protocells reveals naturally occurring chemical modifications to RNA molecules help them properly fold into functional structures

To investigate potential early steps taken by the first life to develop on Earth, researchers have been studying a model of pre-life protocells comprising membraneless compartments. Now, a team of Penn State scientists have found that RNA molecules within these compartments fold better when they have naturally occurring chemical modifications. These modifications that allow for better folding in RNAs may offer a hint into how the molecules evolved from arbitrary chemical compounds to the dynamic, organized building blocks of life. The new study, published by a team of Penn State scientists in the journal Science Advances, used high-throughput genetic sequencing to determine the structure of the RNAs, which also has implications for the design of delivery methods for RNA-based therapeutics that rely on properly folded RNAs to function.

Double Trouble: Infamous “Eagle Killer” Bacterium Produces Not One, But Two Toxins

Colony of A. hydrillicola
Photo Credit: Lenka Štenclová

The cyanobacterium Aetokthonos hydrillicola produces not just one, but two highly potent toxins. In the latest issue of the journal Proceedings of the National Academy of Sciences (PNAS), an international team led by Martin Luther University Halle-Wittenberg (MLU) and Freie Universität Berlin describes the second toxin, which had remained elusive until now. Even in low concentrations, it can destroy cells and is similar to substances currently used in cancer treatment. Two years ago, the same team established that the first toxin from the cyanobacterium is the cause of a mysterious disease among bald eagles in the USA.

Aetokthonos hydrillicola is particularly challenging for researchers. It is notoriously difficult to cultivate and produces one of its toxins only under specific conditions. The fact that it produces two toxins with very different chemical makeups is also unusual. Cyanobacteria normally produce only one toxin - and A. hydrillicola was established as the source of aetokthonotoxin in 2021. This discovery was made by Professor Susan Wilde from the University of Georgia (USA) and Professor Timo Niedermeyer, who worked at MLU until July 2023 and has now joined the researchers at Freie Universität Berlin. This toxin solved a riddle that had kept scientists busy for decades: it triggers the disease vacuolar myelinopathy (VM) among bald eagles in the United States. VM causes holes to form in the brain and, as a result, the birds lose control of their bodies. Science ran the breakthrough as a cover story at the time, and the international team picked up several awards for its work.

Study sheds new light on strange lava worlds

Lava worlds are likely still in the early stages of their evolution, as some theories suggest Earth too was once entirely molten.
Image Credit: NASA’s Goddard Space Flight Center/Chris Smith (KBRwyle)

Lava worlds, massive exoplanets home to sparkling skies and roiling volcanic seas called magma oceans, are distinctly unlike the planets in our solar system.  

To date, nearly 50% of all rocky exoplanets yet discovered have been found capable of maintaining magma on their surfaces, likely because these planets are so close to their host stars they orbit in fewer than 10 days. Being so close causes the planet to be bombarded by harsh weather and forces surface temperatures to the extreme, making it all but completely inhospitable to life as we know it today. 

Now, in a new study, scientists have shown that these sweeping molten oceans have a large influence on the observed properties of hot rocky Super-Earths, such as their size and evolutionary path.  

Their research, published recently in The Astrophysical Journal, found that due to lava’s extremely compressible nature, oceans of magma can cause lava-rich planets without atmospheres to be modestly denser than similarly sized solid planets as well as impact the structure of their mantles, the thick inner layer that surrounds a planet’s core.  

From Seafloor to Space: New Bacterial Proteins Shine Light on Climate and Astrobiology

Methane clathrate (white, ice-like material) under a rock from the seafloor of the northern Gulf of Mexico. Deposits such as these demonstrate that methane and other gases cross the seafloor and enter the ocean.
Photo Credit: NOAA

Gigatons of greenhouse gas are trapped under the seafloor, and that’s a good thing. Around the coasts of the continents, where slopes sink down into the sea, tiny cages of ice trap methane gas, preventing it from escaping and bubbling up into the atmosphere.

While rarely in the news, these ice cage formations, known as methane clathrates, have garnered attention because of their potential to affect climate change. During offshore drilling, methane ice can get stuck in pipes, causing them to freeze and burst. The 2010 Deepwater Horizon oil spill is thought to have been caused by a buildup of methane clathrates.

But until now, the biological process behind how methane gas remains stable under the sea has been almost completely unknown. In a breakthrough study, a cross-disciplinary team of Georgia Tech researchers discovered a previously unknown class of bacterial proteins that play a crucial role in the formation and stability of methane clathrates.

Researcher to help send swarm of marine robots on climate change quest beneath ocean ice

Retreating ice has exposed the rocky shoreline of Cape Rasmussen on the Antarctic Peninsula. Xi Yu, a West Virginia University engineer, is leading robotics research that could help a nationwide consortium of researchers learn more about glacial melt and changing levels of ocean ice.
Phot Credit: Derek Ford/University of Hawaii, Manoa

Research from West Virginia University mechanical and aerospace engineer Xi Yu could help scientists reach ocean waters hidden away beneath ice shelves. The inaccessible waters under ocean ice contain information critical to understanding the impact of climate change, and Yu said she believes multiple marine robots, carried and coordinated by an intelligent mothership, can reach those depths and communicate what they learn.

An assistant professor at the Benjamin M. Statler College of Engineering and Mineral Resources and a member of WVU Robotics, Yu has received National Science Foundation support for a three-year project developing technologies to control swarms of “passenger robots,” intended for release by their autonomous mothership into an icy subaquatic world.

She is part of a coast-to-coast network of oceanographers and engineers who have come together to collaborate on the increasingly urgent problem of how to access oceanic ice cavities. The community of partners working together toward the proof-of-concept mothership-and-passenger system originated at Oregon State University and has expanded outward to include computer engineers, roboticists, oceanographers and glaciologists from Brigham Young, Temple, Purdue and the Woods Hole Oceanographic Institution, in addition to WVU.

Deciphering the secrets of the brain

Adrian Wanner is delighted with the exceptional international recognition from the US National Institute of Health (NIH).
Photo Credit: Scanderbeg Sauer Photography

PSI researchers are to receive funding from the US National Institutes of Health (NIH) as part of its “BRAIN Initiative”. Their aim is to produce a comprehensive map of a mouse’s brain.

Unlocking the secrets of the brain, especially its architecture and wiring, is one of the big challenges in modern life sciences. That is why the National Institutes of Health (NIH) in the USA, one of the world’s largest research agencies, has included this in its program. As part of the NIH BRAIN Initiative, a Swiss researcher has now been awarded a major grant of up to 2.6 million US dollars. The neurobiologist Adrian Wanner, a group leader at the Paul Scherrer Institute PSI, is the project’s principal investigator. Andreas Schaefer from the Francis Crick Institute in London is also closely involved.

The NIH’s decision to invest such a large sum in a project at a Swiss institute demonstrates the exceptional competitiveness of Swiss researchers and confirms PSI’s position as a center for world-class research. “For a young research group leader to receive such a large grant, especially from another country, is by no means commonplace; it testifies to his great scientific talent and the confidence that the international community has in Switzerland as a research location,” says Gebhard Schertler, Head of the Department of Biology and Chemistry, who is delighted with the good news from the United States. Schaefer adds, “This funding will further strengthen the existing collaboration between our groups and institutes.”