Search

Soybean mosaic virus (SMV) is a potyvirus that reduces soybean yield and seed quality worldwide. Here, the authors reveal that the resistance gene Rsv4 encodes an RNase H family protein with dsRNA-degrading activity, and it can enter the viral replication compartment and degrade viral dsRNA.

Returned samples from the carbonaceous asteroid Ryugu provide pristine information on the original aqueous alteration history of the Solar System. Here, the authors utilize Breunnerite grain and magnesium isotope chemistry to reveal cation partitioning during aqueous alteration of asteroid Ryugu.

In this study, the authors report primordial aqueous alteration signatures in water-soluble organic molecules from the carbonaceous asteroid Ryugu. This provides evidence o coevolutionary aqueous alteration between water and organics in this asteroid.

Ryugu is more primitive than carbonaceous chondrites, according to elevated noble gas concentrations. Elevated Xe and its isotopic composition further provide constraints on fractionation of the solar composition to form the early planetary components.

The sample taken from carbonaceous asteroid Ryugu and brought back to Earth by the Hayabusa2 spacecraft contains outer Solar System-derived materials uncontaminated by terrestrial processes. Even CI carbonaceous chondrites, despite their closeness to solar abundances, are not pristine.

Although metals cannot be ferroelectric in the strict sense of the term, it has long been predicted that they can undergo structural transitions that share similarities with ferroelectricity. LiOsO₃ is now shown to be an experimental realization of such a ferroelectric-like metal.

Both poles of asteroid Ryugu, the target of space mission Hayabusa2, preserve the least processed material by space weathering. Here, the authors show detection of 700 nm absorption band in the polar spectra of Ryugu, that allows to constrain the hydrothermal history of its spectrally blue parent body.

A comparison of copper and zinc isotopic measurements between the Ryugu samples and various carbonaceous chondrites excludes any genetic link between the two except for the CI (Ivuna-type) chondrites. Ryugu-like material might have accounted for ~5% of Earth’s mass.

Thermal imaging data obtained from the spacecraft Hayabusa2 reveal that the carbonaceous asteroid 162173 Ryugu is an object of unusually high porosity.

Thrombospondin-1 (THBS1) is a matricellular protein highly expressed in inflammatory processes, including cancer. Here the authors show that bone-marrow derived monocyte-like cells are the primary source of THBS1 in colorectal cancer, associated with mesenchymal characteristics, immunosuppression and a poor prognosis.

The molecular atlas of soluble organic compounds from Ryugu shows unprecedented molecular complexity and diversity resulting from alteration on a low temperature, water rich parent body.

A new study of samples from the Ryugu asteroid reveal a greater diversity of macromolecular organic matter than that found in related carbonaceous meteorites. Researchers find distinct populations of alkyl-aromatic grains, and organic carbonate is found with coarse-grained clay minerals

The asteroid Ryugu experienced aqueous alteration under changing temperature and redox conditions, according to an isotopic analysis of secondary calcite and dolomite grains in samples from Ryugu obtained by the Hayabusa2 spacecraft.

Electron holography discovered nonmagnetic framboids and many iron nanoparticles with a vortex magnetic flux formed by magnetite reduction due to a micrometeoroid impact on asteroid Ryugu, providing a new way to study the Solar System magnetic field.

Iron nitride (Fe₄N) is detected on magnetite particles within the Ryugu sample returned by Hayabusa2. It is probably the product of impacts of nitrogen-rich dust from the outer Solar System on the surface of Ryugu, indicative of a flux of N-rich dust in the inner Solar System.

The asteroid Ryugu samples are by far the freshest extraterrestrial carbonaceous material. The authors report soluble ions and organic sulfur molecules linked with primordial brine and prebiotic organic evolution of the primitive asteroid.

Amino acid concentrations from 2 particles returned from different touchdown sites on the surface of Ryugu are reported. Differences in chemistry suggest different levels of aqueous alteration are recorded at the 2 sampled locations.

Uracil was identified in the sample returned from the asteroid Ryugu. Having been provided to the early Earth as a component in such asteroidal materials, these molecules might have played a role for prebiotic chemical evolution on the early Earth

Chondrule-like objects and CAIs in the Ryugu samples are early generations of chondrules and possibly oldest solids in the Solar System. They were transported from the inner solar nebula to the formation ___location of the Ryugu original parent body.

The returned samples from Hayabusa2 show that C-type asteroid Ryugu experienced various steps of mineralogical alteration within only 1–2 million years after accretion.

Signatures of impact-induced shocks are found on Ryugu returned particles. Observations show that they happened at moderate temperatures (~500 °C) and pressures (~2 GPa) and did not dehydrate the particles substantially, suggesting that bigger meteoroids, rather than micrometeoroids, provide Earth with hydrated minerals.

Oxygen isotopic measurements from the Ryugu returned sample suggest that primitive hydrated carbonaceous chondrites are an important source of early water and other volatiles to Earth, despite being underrepresented in our meteorite collection due to their preferential destruction during atmospheric entry.

A close-up look at the action of space weathering on carbonaceous asteroids, provided by Ryugu’s returned samples, highlights its role on the dehydration of the first micrometre-thick layer of the surface, possibly hiding a water-rich interior. The depth of the 2.7 µm hydration band may be an indication of the level of space weathering withstood by a C-type asteroid.

The aqueous activity responsible for carbonate formation on Ryugu happened much earlier—less than 1.8 million years after CAI formation—than estimates (4–6 Myr) from carbonaceous chondrite meteorites. Ryugu’s parent body either was smaller than ∼20 km in diameter or was disrupted before reaching the high temperatures required.

About 0.5% by volume of the Ryugu particle C0009 is made up of anhydrous silicates, mostly olivines, despite the extensive aqueous alteration of its parent body. Such aggregates, rich in ¹⁶O, were present in Ryugu’s protolith and survived fluid activity.

The Hayabusa2 spacecraft returned 5.4 g of material from the asteroid Ryugu. A first analysis of the samples found an estimated density of 1,282 ± 231 kg m⁻³, considerably lower than even the most porous meteorites. Together with preliminary spectral analysis, these results indicate that Ryugu is similar to CI chondrites, but darker, more porous and more brittle.

Samples returned from Ryugu contain fresher material than the space weathered outer asteroid surface observed by remote sensing, according to a comparison of spectral data from returned samples, orbital observations and Murchison meteorite samples.