Lost in Translation: How "Risky" Amino Acids Abort Elongation in Protein Synthesis

Elongation, a crucial step in the translation process of protein synthesis, gets disrupted by amino acid sequences with an abundance of N-terminal aspartic and glutamic acid residues in eukaryotic cells, discovered researchers from Tokyo Tech and University of Hyogo. The team's findings show that these "risky" amino acids can destabilize the ribosomal machinery. As a consequence, most proteomes tend to avoid incorporating them at the N-terminals of peptide sequences, indicating a bias in amino acid distribution.

Life depends on the precise functioning of several proteins synthesized in cells by ribosomes. This diverse set of proteins, known as a proteome, is maintained by the robust translation elongation of amino acid sequences taking place in the ribosomes. The translation mechanisms which ensure that nascent chains of polypeptides—long chains of amino acids—are elongated without getting detached are conserved in all living organisms. However, the rates of elongation are not constant. Elongation is often interrupted by interactions between positively charged nascent polypeptides and negatively charged ribosomal RNA.

Astronomers use ‘little hurricanes’ to weigh and date planets around young stars

The protoplanetary disc surrounding the young star HL Tauri. These new ALMA observations reveal substructures within the disc that have never been seen before and even show the possible positions of planets forming in the dark patches within the system. 
Image Credit: ALMA (ESO/NAOJ/NRAO)

Researchers from the University of Cambridge and the Institute for Advanced Study have developed a technique, which uses observations of these ‘hurricanes’ by the Atacama Large Millimeter/submillimeter Array (ALMA) to place some limits on the mass and age of planets in a young star system.

Pancake-like clouds of gases, dust and ice surrounding young stars – known as protoplanetary discs - are where the process of planet formation begins. Through a process known as core accretion, gravity causes particles in the disc to stick to each other, eventually forming larger solid bodies such as asteroids or planets. As young planets form, they start to carve gaps in the protoplanetary disc, like grooves on a vinyl record.

Even a relatively small planet – as small as one-tenth the mass of Jupiter according to some recent calculations – may be capable of creating such gaps. As these ‘super-Neptune’ planets can orbit their star at a distance greater than Pluto orbits the Sun, traditional methods of exoplanet detection cannot be used.

In addition to the grooves, observations from ALMA have shown other distinct structures in protoplanetary discs, such as banana- or peanut-shaped arcs and clumps. It had been thought that at least some of these structures were also driven by planets.

Monkeypox viruses remain sensitive to the available drugs

Monkeypox Virus
Illustration Credit: Samuel F. Johanns

The three antiviral drugs commonly used to treat mpox viruses (monkeypox viruses) are also effective against the viruses from the current outbreak. This has been shown in cell culture experiments by scientists at Goethe University Frankfurt/University Hospital Frankfurt and the University of Kent in Canterbury, Great Britain.

The mpox virus is closely related to the smallpox virus (variola virus), which caused large, deadly outbreaks before it was eradicated by vaccination at the end of the 1970s. While the smallpox virus led to very severe disease progression with a death rate of about 30 percent, mpox is milder. Nevertheless, the mortality rate is still about three percent. Particularly at risk of a severe course of the disease are people with a weakened immune system, elderly persons, pregnant women, newborn babies and young children. Until recently, mpox outbreaks only occurred in certain parts of Africa when humans became infected through contact with wild animals, typically rodents such as the Gambian pouched rat and the rope squirrel.

However, in May 2022 a first large mpox outbreak outside Africa was detected; the virus spread solely through human-to-human transmission. This ongoing outbreak has so far reached more than 100 countries and been classified by the World Health Organization (WHO) as a "Public Health Emergency of International Concern".

How evolution works

Examples of phenotypic innovations across the eukaryotic tree of life, to which newly developed approaches can be applied.
Graphic Credit: Kenji Fukushima

What genetic changes are responsible for the evolution of phenotypic traits? This question is not always easy to answer. A newly developed method now makes the search much easier.

With its powerful digging shovels, the European mole can burrow through the soil with ease. The same applies to the Australian marsupial mole. Although the two animal species live far apart, they have developed similar organs in the course of evolution - in their case, extremities ideally adapted for digging in the soil.

Science speaks of "convergent evolution" in such cases, when animal, but also plant species independently develop features that have the same shape and function. There are many examples of this: Fish, for example, have fins, as do whales, although they are mammals. Birds and bats have wings, and when it comes to using poisonous substances to defend themselves against attackers, many creatures, from jellyfish to scorpions to insects, have all evolved the same instrument: the venomous sting.

Researchers Find that Wind Turbines Repel Bats in Finnish Forests

Northern bat (Eptesicus nilssonii) is the most common bat in Finland.
Photo Credit: Anna Blomberg

Wind turbines are built at an increasing pace but their effect on nature and animals is poorly known. Researchers from the Universities of Turku and Helsinki in Finland have investigated the impact of wind turbines on bat presence and activity in boreal forests. The results indicate clearly that bats don’t like wind turbines.

The researchers recorded bat acoustic activity for an entire summer at seven wind farms located in forests situated on the western coastline of Finland. By setting up recorders at varying distances from the wind turbines, they were able to see how bat activity and presence differed closer to the turbines as well as further away.

The researchers studied two groups of bats: the Northern bat, which is the most common species in Finland, and the Myotis, a group of five species, including the very common Daubenton’s bat.

“Our results showed that bat presence was impacted by the presence of wind turbines as both studied groups were found more often further away from the wind turbines. Northern bats were repelled up to 800 meters from the wind turbines, but for the Myotis species the negative impact of wind power was even greater than one kilometer, which was the maximum distance we studied”, summarizes lead author, Doctoral Researcher Simon Gaultier from the University of Turku.

A Theory of Rage

Left: Aditya Nair, Caltech graduate student and study's lead author. Photo Credit: J. Ehlert
Center: Ann Kennedy, Theoretical neuroscientist. Photo Credit: Ann Kennedy
Right: David Anderson, Professor of Biology Photo Credit: Courtesy of David Anderson

Have you ever been cut off while driving and found yourself swearing and laying on the horn? Or come home from a long day at work and lashed out at whoever left the dishes unwashed? From petty anger to the devastating violence we see in the news, acts of aggression can be difficult to comprehend. Research has yielded puzzling paradoxes about how rage works in the brain. But a new study from Caltech, pioneering a machine-learning research technique in the hypothalamus, reveals unexpected answers on the nature of aggression.

The hypothalamus is a brain region linked to many innate survival behaviors like mating, hunting, and the fight-or-flight response. Scientists have long believed that neurons in the hypothalamus are functionally specific—that is, certain groups of neurons correlate to certain specific behaviors. This seems to be the case in mating behavior, where neuron groups in the medial preoptic area (MPOA) of the hypothalamus, when stimulated, cause a male mouse to mount a female mouse. These same neurons are active when mounting behavior occurs naturally. The logical conclusion is that these neurons control mounting in mice.

Ludwig Cancer Research study uncovers novel aspect of tumor evolution and potential targets for therapy

 Ping-Chih Ho, Ludwig Lausanne Associate Member
Photo Credit: Ludwig Cancer Research

A Ludwig Cancer Research study has discovered that the immune system’s surveillance of cancer can itself induce metabolic adaptations in the cells of early-stage tumors that simultaneously promote their growth and equip them to suppress lethal immune responses.

Led by Ludwig Lausanne Associate Member Ping-Chih Ho and published in Cell Metabolism, the study details the precise mechanism by which this “immunometabolic editing” of emergent tumors occurs in mouse models of the skin cancer melanoma and identifies a novel biochemical signaling cascade and proteins that orchestrate its effects. Aside from illuminating a previously unknown dimension of tumor evolution, the findings hold significant promise for improving the efficacy of cancer immunotherapy.

“We have uncovered dozens of metabolic enzymes that contribute to immune evasion in melanoma tumors,” said Ho. “These enzymes, as well as some of the individual components of the signaling pathway we’ve identified, represent a rich trove of potential drug targets to undermine the defenses erected by immunometabolic editing. Such drugs could make tumors vulnerable to immune clearance and could also be used in combination with checkpoint blockade and other immunotherapies to overcome the resistance most cancers have to such treatments.”

New approach successfully traces genomic variants back to genetic disorders

Doctors researching DNA and genetics.
Illustration Credit: Julia Fekecs, NHGRI

National Institutes of Health researchers have published an assessment of 13 studies that took a genotype-first approach to patient care. This approach contrasts with the typical phenotype-first approach to clinical research, which starts with clinical findings. A genotype-first approach to patient care involves selecting patients with specific genomic variants and then studying their traits and symptoms; this finding uncovered new relationships between genes and clinical conditions, broadened the traits and symptoms associated with known disorders, and offered insights into newly described disorders. The study was published in the American Journal of Human Genetics.

“We demonstrated that genotype-first research can work, especially for identifying people with rare disorders who otherwise might not have been brought to clinical attention,” says Caralynn Wilczewski, Ph.D., a genetic counselor at the National Human Genome Research Institute’s (NHGRI) Reverse Phenotyping Core and first author of the paper.

Typically, to treat genetic conditions, researchers first identify patients who are experiencing symptoms, then they look for variants in the patients’ genomes that might explain those findings. However, this can lead to bias because the researchers are studying clinical findings based on their understanding of the disorder. The phenotype-first approach limits researchers from understanding the full spectrum of symptoms of the disorders and the associated genomic variants.

New quantum computing architecture could be used to connect large-scale devices

This image shows a module composed of superconducting qubits that can be used to directionally emit microwave photons.
Illustration Credit: Massachusetts Institute of Technology / Courtesy of the researchers

Quantum computers hold the promise of performing certain tasks that are intractable even on the world’s most powerful supercomputers. In the future, scientists anticipate using quantum computing to emulate materials systems, simulate quantum chemistry, and optimize hard tasks, with impacts potentially spanning finance to pharmaceuticals.

However, realizing this promise requires resilient and extensible hardware. One challenge in building a large-scale quantum computer is that researchers must find an effective way to interconnect quantum information nodes — smaller-scale processing nodes separated across a computer chip. Because quantum computers are fundamentally different from classical computers, conventional techniques used to communicate electronic information do not directly translate to quantum devices. However, one requirement is certain: Whether via a classical or a quantum interconnect, the carried information must be transmitted and received.

To this end, MIT researchers have developed a quantum computing architecture that will enable extensible, high-fidelity communication between superconducting quantum processors. In work published today in Nature Physics, MIT researchers demonstrate step one, the deterministic emission of single photons — information carriers — in a user-specified direction. Their method ensures quantum information flows in the correct direction more than 96 percent of the time.

James Webb Telescope Reveals Milky Way-like Galaxies in Young Universe

The power of JWST to map galaxies at high resolution and at longer infrared wavelengths than Hubble allows it look through dust and unveil the underlying structure and mass of distant galaxies. This can be seen in these two images of the galaxy EGS23205, seen as it was about 11 billion years ago. In the HST image (left, taken in the near-infrared filter), the galaxy is little more than a disk-shaped smudge obscured by dust and impacted by the glare of young stars, but in the corresponding JWST mid-infrared image (taken this past summer), it’s a beautiful spiral galaxy with a clear stellar bar.
Image Credit: NASA/CEERS/University of Texas at Austin

New images from NASA’s James Webb Space Telescope (JWST) reveal for the first-time galaxies with stellar bars — elongated features of stars stretching from the centers of galaxies into their outer disks — at a time when the universe was a mere 25% of its present age. The finding of so-called barred galaxies, similar to our Milky Way, this early in the universe will require astrophysicists to refine their theories of galaxy evolution.

Prior to JWST, images from the Hubble Space Telescope had never detected bars at such young epochs. In a Hubble image, one galaxy, EGS-23205, is little more than a disk-shaped smudge, but in the corresponding JWST image taken this past summer, it’s a beautiful spiral galaxy with a clear stellar bar.

“I took one look at these data, and I said, ‘We are dropping everything else!’” said Shardha Jogee, professor of astronomy at The University of Texas at Austin. “The bars hardly visible in Hubble data just popped out in the JWST image, showing the tremendous power of JWST to see the underlying structure in galaxies,” she said, describing data from the Cosmic Evolution Early Release Science Survey (CEERS), led by UT Austin professor, Steven Finkelstein.