Targeting Allele-Specific Faulty MRNA In SCNA2 Mutation Patients

When an individual is born with genetic defects, there are a few ways to deal with the impact of the faulty genes. The most extreme solution is direct DNA editing to repair the mutation, while the treatment of symptoms with medication is the least invasive, though this comes with its own set of disadvantages. Antisense therapy keeps a middle ground here, by targeting the messenger RNA (mRNA) that forms the bridge between DNA and the translation into a functional protein by the ribosome.

In a recent study by [Olivia Kim-McManus] et al. antisense therapy with an allele-specific feature was demonstrated in two individuals with SCN2A mutations. These mutations had resulted in severe epilepsy and developmental disorders, due to how instrumental this gene is for normal functioning of the human central nervous system (CNS) where it regulates the initiation of action potentials.

Although SCN2A mutations are rarely inherited, for the approximately 1 in 80,000 affected the consequences can be quite dramatic. The two major types of mutations are classified as gain-of-function (GoF) and loss-of-function (LoF) with respectively hyper- and hyposensitivity of the resulting NAv1.2 sodium channels.

This translates especially in the case of GoF mutations into various symptoms, ranging from mild to severe (daily) epileptic attacks starting as an infant, stalled neurodevelopment and various types of autism (ASD). Often sodium channel blockers are prescribed for the GoF cases to limit epileptic attacks.

Usually with the responsible mutations only a single copy of the gene is affected, so while regular antisense therapy could be used, this would risk also modifying the healthy SCN2A mRNA copy. To get around this, an individualized treatment was developed, targeting the allele with the mutated gene for the two patients in the study: 9- and 14-year old boys with severe developmental and epileptic encephalopathies (DEE) that had left them with daily seizures and despite sodium-channel blockers and other typical medications.

Study outcome of the 14-year old boy with DEE after ASO therapy. (Credit: Kim-McManus et al., Nature Medicine, 2026)
Study outcome of the 14-year old boy with DEE after ASO therapy. (Credit: Kim-McManus et al., Nature Medicine, 2026)

During the trial, the 9-year old boy received 12 doses over 24 months of antisense oligonucleotides (ASOs) adapted to his affected allele, allowing for the cessation of the anti-seizure medication phenytoin, with an overall reduction in seizures. In the case of the 14-year old boy 8 doses were administered over 16 months, resulting in an average of two seizures a day being reduced to zero.

Although the focus of the study was on treating these seizures, by addressing the underlying cause of faulty mRNA transcriptions, changes in the neurodevelopmental state could also be observed. In particular language and motor skills improved, with erratic and irritable behavior reducing. The by then 15-year year old boy was able to walk unassisted, showing clear progression from the previous infantile state.

The advantage of ASOs over typical anti-seizure medication is of course that it directly addresses the faulty mRNA and thus the resulting faulty sodium channels. Since ASOs tend to hang around in a cell for a considerable amount of time, they could be quite a viable alternative treatment even for less severe cases. Whether early application of individualized ASOs in affected infants could lead to a more or less normal neurodevelopment would also be an interesting study question.

Naturally, directly addressing the faulty gene or upregulating the healthy gene would be the ideal and permanent solution, with research here also underway in mice models with the use of CRISPR-based tools.

V Formation Flying Of Birds Is Explained By A Minimal Wake–Vortex Model

Although it’s commonly suspected that migratory birds fly in a ‘V’ formation due to this saving energy for the birds in the slipstream, understanding the exact aerodynamics behind this and how it affects the way that the birds use their wings to maintain this optimal pattern. After all, unlike airplanes and cars, our feathered avian dinosaur friends need to flap their wings if they want to have any chance of staving off plummeting back to Earth. Recent research by Brown University researchers now have provided a simulated model that answers many questions.

The major question was how this would work in the up- and down-wash zones created in this type of formation, with every bird following the lead bird dealing with the vortices created by the flapping of the wings of the bird before them. These wake vortices are quite complex, and thus required careful modelling to make sense of them.

As described in the paper by [Olivia Pomerenk] et al., the model is based on northern bald ibises, taking into account live-bird measurements for validation of the model. The main effect that can be observed is a reduced flapping amplitude, leading to an 11% energy savings for the birds in the leader’s wake.

The main advantage of having such a model is of course that it provides insight into the kinematic and aerodynamic mechanisms, meaning the ability to model virtual flocks of birds, predict the efficiency of specific in-flight configurations, and apply the lessons to swarms of drones, or whatever else we want to put in the air.

Detection Of A Four-Carbon Sugar In Interstellar Space

Although life tends to find a way, something first has to kickstart said lifeforms. Exactly how the first biological cells formed on Earth – and potentially on other worlds – remains an enduring mystery. Some theories point to the early Earth’s surface conditions as a viable laboratory for the self-assembly of the first viable membranes, RNA, DNA and associated molecular machinery, while seeding of the Earth’s primitive atmosphere by sugars and other precursors from asteroids and kin is required in other theories.

Recently [Izaskun Jiménez-Serra] et al. added to this debate with the reported detection of four-carbon sugars in the form of erythrulose in the interstellar medium. Using the 40 meter radio telescope at Yebes and the 30 meter radio telescope at Granada the signatures of this sugar was detected in a molecular cloud near the center of the Milky Way.

These sugars likely form on these interstellar dust grains from more basic two-carbon aldehydes and alcohols, with them providing conceivably a source of energy for early metabolic processes of developing lifeforms. This specific type of sugar is highly prevalent in Earth’s fruits, and thus its prevalence in interstellar space is at the very least an interesting coincidence, if not another puzzle piece in the overarching question of abiogenesis.

Earth-like LHS 1140b May Feature The First Atmosphere Found On Exoplanet

Finding another planet outside of our solar system that can comfortably be called ‘Earth-like’ is one of those discoveries that — if confirmed — would be a major event. The complication here is that with every exoplanet that we discover through observations, determining the type of planet is hard enough, never mind figuring out whether it has an atmosphere, much less what’s in that atmosphere. This makes a recent report on LHS 1140 b rather exciting, as it strongly suggests that this super-Earth may have something close to an Earth-like atmosphere.

In the paper by [Collin Cherubim] and others in Science, the findings of helium occasionally escaping from its atmosphere have led to considerable excitement, as this time-variable atmospheric escape of helium suggests a helium-rich upper atmosphere that’s further depleted in hydrogen.

It should be noted, of course, that these assumptions are based on observations from roughly 49 light-years away, so there’s always some room for later adjustments. Even if confirmed, the star that LHS 1140b orbits is a red dwarf, with a nearly 25-day orbital period and light levels less than half of what Earth receives from the Sun. This would make the surface of LHS 1140b with its proposed oceans rather dim, even if it’s conceivably at temperatures well within the comfort range of us Earth-based mammals.

At 49 light-years distance, it’s also not close enough that — barring an FTL drive — we could do direct observations or visitations, but if these results hold, it’d be on the short list along with a number of other plausibly habitable exoplanets to check out once we build that first warp drive-powered starship.

A scanning-electron micrograph is shown of a cricket's body, focusing on the head, which has been sliced off just above the eyes.

Cross-Sectioning Crickets With A Femtosecond Laser

Unlike most cutting lasers, femtosecond lasers don’t vaporize materials; rather, they produce such short, intense bursts of light that the affected region is ablated without having the chance to heat its surroundings. This makes them good at cutting away material without damaging the surroundings, something [Ben Krasnow] exploited to cut cross-sections of samples while still in a scanning-electron microscope.

In this case, the samples were crickets, and before imaging they had to be prepared. First, the bodies were soaked in glutaraldehyde to cross-link the proteins and stabilize the structure. Next, a series of solvent exchanges replaced the water in the bodies with a low-surface-tension solvent; this meant that during the next step, drying, surface tension wouldn’t distort the crickets’ internal structure. Finally, the insect bodies were charred under argon, which made the bodies conductive and more absorptive to laser light.

The laser itself and the scanning galvo are mounted outside the microscope, and shine in through a transparent window. To protect the detector and electron optics from a spray of ablated carbon, a servo motor swings an aluminium shutter between these and the sample while the laser is active. This caused some mysterious problems during testing: after the first ablation run, the electron microscope’s image would contain so much noise as to be unusable, but it would improve over time. As it turned out, the shutter was painted, and the other side of the paint was getting coated with charged carbon particles. This created a small capacitor which disrupted the electron optics as it discharged. Eventually, after solving this and a few other strange problems, [Ben] was able to take several time-lapse videos of the laser gradually ablating a cricket, 30 microns at a time, revealing its inner structure.

Although scanning-electron microscopes are unfortunately shard to come by, it’s still possible to restore a secondhand microscope or, as [Ben] did, build your own. Femtosecond lasers are yet more inaccessible, though they can be used to replicate themselves.

Continue reading “Cross-Sectioning Crickets With A Femtosecond Laser”

How Octopuses Hacked Their Ribosome To Become Smart

A fascinating aspect in evolutionary biology is that of convergent evolution — whereby similar structures and functions evolve independently from each other. The highly advanced nervous system of octopuses is a good example here, displaying levels of intelligence and capabilities far beyond those of other cephalopods and matching that of primates, despite no evolutionary link here. Exactly how octopuses developed this rather unique capability remained a mystery, though recent research by [Rishav Mitra] points at the rather unique ribosomes in these animals.

Ribosomes are the molecular machinery at the core of each cell that enable the synthesis of proteins. Due to their highly crucial role, they tend to remain evolutionary unchanged, which makes the big change observed in the octopus (i.e. order Octopoda) in the form of this H88 rRNA break quite remarkable.

Common octopus (<i>Octopus vulgaris</i>). (Credit: Albert Kok, Wikimedia)
Common octopus (Octopus vulgaris). (Credit: Albert Kok, Wikimedia)

This H88 break increases the accuracy of translated proteins, something that is essential for complex nervous systems as it reduces cases of misfolded proteins (proteinopathy). Because of how well-preserved ribosomes are across species, the researchers were able to run a number of experiments including a similar rRNA break in E. coli that confirmed many of the assumptions about how these octopus ribosomes performed.

Since proteinopathy results in misfolded proteins that are either useless or harmful to the organism – as seen in various human diseases – this can especially harm long-lived cells like neurons. Unsurprisingly, we can see a similar change to ribosomes in other animal groups, including that of us primates. Although the reasons for octopuses to develop more complex nervous systems wasn’t due to social pressures but rather to cope with highly complex and dynamic environments, it would seem that both types of environmental pressures led to the same convergent path, with a little ribosomal help.

Even Chemical Bonds Obey Einstein’s Relativity

Although Einstein’s Theory of Relativity is typically associated with really large and really heavy things like planets in solar systems and big things in universes in general, it turns out that even at an atomic scale its effects can be measured. These are the findings of Brown University scientists, whose measurements on very heavy elements indicate the presence of relativistic bonds.

Unfortunately the paper by [Kirk A. Peterson] et al. in Science is paywalled without a convenient ArXiv version to ogle details beyond the supplemental, but the Brown press release gives quite a few details by itself, including the use of photoelectron spectroscopy to measure the strength of the bonds between the examined nuclei.

The essential summary is that our concept of how triple bonds work may be flawed, with the assumption that there are distinct sigma and pi bonds, the latter being the awkward, weaker ‘side bonds’ where the overlapping atomic orbitals do not directly line up as with a sigma bond. As it turns out, if there’s enough mass involved, relativistic effects smudge both types of bonds together into a hybrid type of bond.

Although the sigma-pi triple bond theory still seems to hold up for lighter atomic nuclei, in the case of the examined bismuth-carbon triple bond, the typical, slightly radioactive bismuth-209 nucleus with atomic number 83 is heavy enough to affect the orbital mechanics and with it the chemical bonds that these produce.

This is an important finding, as it affects our basic understanding of how strong the bonds between certain elements are. Pi bonds are after all significantly weaker than sigma bonds, so a hybrid form would effectively make triple bonds involving a heavier element stronger than one between lighter elements.